Patran 2010 Reference Manual Part 2: Geometry Modeling

Patran 2010

Reference ManualPart 2: Geometry Modeling

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C o n t e n t sGeometry Modeling - Reference Manual Part 2

Geometry Modelingerence Manual Par

1 Introduction to Geometry Modeling

Overview of Capabilities 2

Concepts and Definitions 4Parameterization 4Topology 10Connectivity 16Effects of Parameterization, Connectivity and Topology in Patran 18Global Model Tolerance & Geometry 19

Types of Geometry in Patran 20Trimmed Surfaces 20Solids 24Parametric Cubic Geometry 25Matrix of Geometry Types Created 27

Building An Optimal Geometry Model 31Building a Congruent Model 31Building Optimal Surfaces 33Decomposing Trimmed Surfaces 38Building B-rep Solids 41Building Degenerate Surfaces and Solids 42

2 Accessing, Importing & Exporting Geometry

Overview 46

Direct Geometry Access of CAD Geometry 47Accessing Geometry Using Patran Unigraphics 47Accessing Geometry Using Patran ProENGINEER 54

PATRAN 2 Neutral File Support For Parametric Cubic Geometry 57

3 Coordinate Frames

Coordinate Frame Definitions 60

Geometry Modeling - Reference Manual Part 2

ii

Overview of Create Methods For Coordinate Frames 64

Translating or Scaling Geometry Using Curvilinear Coordinate Frames 67

4 Create Actions

Overview of Geometry Create Action 72

Creating Points, Curves, Surfaces and Solids 78Create Points at XYZ Coordinates or Point Locations (XYZ Method) 78Create Point ArcCenter 82Extracting Points 84Interpolating Points 94Intersecting Two Entities to Create Points 100Creating Points by Offsetting a Specified Distance 110Piercing Curves Through Surfaces to Create Points 112Projecting Points Onto Surfaces or Faces 115Creating Curves Between Points 120Creating Arced Curves (Arc3Point Method) 130Creating Chained Curves 133Creating Conic Curves 135Extracting Curves From Surfaces 139Creating Fillet Curves 145Fitting Curves Through a Set of Points 149Creating Curves at Intersections 151Manifold Curves Onto a Surface 161Creating Curves Normally Between a Point and a Curve (Normal Method) 168Creating Offset Curves 171Projecting Curves Onto Surfaces 176Creating Piecewise Linear Curves 183Creating Spline Curves 185Creating Curves Tangent Between Two Curves (TanCurve Method) 193Creating Curves Tangent Between Curves and Points (TanPoint Method) 195Creating Curves, Surfaces and Solids Through a Vector Length (XYZ Method)

199Creating Involute Curves 203Revolving Curves, Surfaces and Solids 208Creating Orthogonal Curves (2D Normal Method) 214Creating 2D Circle Curves 222Creating 2D ArcAngle Curves 226Creating Arced Curves in a Plane (2D Arc2Point Method) 229

iiiCONTENTS

Creating Arced Curves in a Plane (2D Arc3Point Method) 237Creating Surfaces from Curves 240Creating Composite Surfaces 250Decomposing Trimmed Surfaces 254Creating Surfaces from Edges (Edge Method) 256Extracting Surfaces 259Creating Fillet Surfaces 265Matching Adjacent Surfaces 269Creating Constant Offset Surface 271Creating Ruled Surfaces 273Creating Trimmed Surfaces 277Creating Surfaces From Vertices (Vertex Method) 286Extruding Surfaces and Solids 288Gliding Surfaces 293Creating Surfaces and Solids Using the Normal Method 297Creating Surfaces from a Surface Mesh (Mesh Method) 304Creating Midsurfaces 306

Creating Solid Primitives 311Creating a Solid Block 311Creating Solids from Surfaces (Surface Method) 327Creating a Boundary Representation (B-rep) Solid 337Creating a Decomposed Solid 339Creating Solids from Faces 342Creating Solids from Vertices (Vertex Method) 345Gliding Solids 347

Feature Recognition (Pre-release) 350Feature Types 350Overview of the Feature Recognition Modules 350Feature Recognition 352Edit Hole Feature 358Edit Hole Feature using Radius Constraint 361Edit Blend Feature 364Edit Blend Feature using Radius Constraint 367Edit Chamfer Feature 370Edit Chamfer Feature using Height Constraint 373Edit Feature Parameters 376Show Hole Feature 377Show Hole Feature using Radius Constraint 378Show Blend Feature 379Show Blend Feature using Radius Constraint 380Show Chamfer Feature 381Show Chamfer Feature using Height Constraint 382


iv

Show Feature Information 383Delete Hole Feature 384Delete Hole Feature using Radius Constraint 385Delete Blend Feature 386Delete Blend Feature using Radius Constraint 387Delete Chamfer Feature using Height Constraint 388Delete Chamfer Feature 389Delete Any Feature 390Clear Feature 391

Creating Coordinate Frames 393Creating Coordinate Frames Using the 3Point Method 393Creating Coordinate Frames Using the Axis Method 395Creating Coordinate Frames Using the Euler Method 397Creating Coordinate Frames Using the Normal Method 401Creating Coordinate Frames Using the 2 Vector Method 404Creating Coordinate Frames Using the View Vector Method 405

Creating Planes 407Creating Planes with the Point-Vector Method 407Creating Planes with the Vector Normal Method 408Creating Planes with the Curve Normal Method 410Creating Planes with the Plane Normal Method 414Creating Planes with the Interpolate Method 415Creating Planes with the Least Squares Method 418Creating Planes with the Offset Method 424Creating Planes with the Surface Tangent Method 426Creating Planes with the 3 Points Method 430

Creating Vectors 433Creating Vectors with the Magnitude Method 433Creating Vectors with the Interpolate Method 434Creating Vectors with the Intersect Method 435Creating Vectors with the Normal Method 437Creating Vectors with the Product Method 444Creating Vectors with the 2 Point Method 446

Creating P-Shapes 449Rectangle 449Quadrilateral 449Triangle 450Disc 451Cylinder 452Cone 453Sphere 454

vCONTENTS

Paraboloid 455Five-Sided Box 456Six-Sided Box 457

Edit P-Shapes 459

5 Delete Actions

Overview of the Geometry Delete Action 462

Deleting Any Geometric Entity 463

Deleting Points, Curves, Surfaces, Solids, Planes or Vectors 464

Deleting Coordinate Frames 466

6 Edit Actions

Overview of the Edit Action Methods 468

Editing Points 470Equivalencing Points 470

Editing Curves 472Breaking Curves 472Blending a Curve 482Disassembling a Chained Curve 485Extending Curves 488Merging Existing Curves 502Refitting Existing Curves 506Reversing a Curve 508Trimming Curves 511

Editing Surfaces 518Surface Break Options 518Blending Surfaces 536Disassembling Trimmed Surfaces 539Editing Edges from Surfaces 542Matching Surface Edges 546Extending Surfaces 551Refitting Surfaces 566Reversing Surfaces 568Sewing Surfaces 570Subtracting Surfaces 572Trimming Surfaces to an Edge 573


vi

Adding a Fillet to a Surface 575Adding a Hole to Surfaces 576Removing a Hole from Trimmed Surfaces 582Adding a Vertex to Surfaces 584Removing a Vertex from Trimmed Surfaces 586

Editing Solids 589Breaking Solids 589Blending Solids 605Disassembling B-rep Solids 608Refitting Solids 611Reversing Solids 616Solid Boolean Operation Add 617Solid Boolean Operation Subtract 619Solid Boolean Operation Intersect 621Creating Solid Edge Blends 623Imprinting Solid on Solid 627Solid Shell Operation 629

Editing Features 632Suppressing a Feature 632Unsuppressing a Feature 633Editing Feature Parameters 634Feature Parameter Definition 635

7 Show Actions

Overview of the Geometry Show Action Methods 638The Show Action Information Form 639

Showing Points 640Showing Point Locations 640

Showing Point Distance 642Showing the Nodes on a Point 656

Showing Curves 658Showing Curve Attributes 658Showing Curve Arc 659Showing Curve Angle 661Showing Curve Length Range 663Showing the Nodes on a Curve 665

Showing Surfaces 667Showing Surface Attributes 667

viiCONTENTS

Showing Surface Area Range 669Showing the Nodes on a Surface 670Showing Surface Normals 672

Showing Solids 675Showing Solid Attributes 675

Showing Coordinate Frames 677Showing Coordinate Frame Attributes 677

Showing Planes 679Showing Plane Attributes 679Showing Plane Angle 680Showing Plane Distance 682

Showing Vectors 684Showing Vector Attributes 684

8 Transform Actions

Overview of the Transform Methods 686

Transforming Points, Curves, Surfaces, Solids, Planes and Vectors 689

Translating Points, Curves, Surfaces, Solids, Planes and Vectors 689Rotating Points, Curves, Surfaces, Solids, Planes and Vectors 703Scaling Points, Curves, Surfaces, Solids and Vectors 713Mirroring Points, Curves, Surfaces, Solids, Planes and Vectors 724Moving Points, Curves, Surfaces, Solids, Planes and Vectors by Coordinate Frame Reference (MCoord Method) 732Pivoting Points, Curves, Surfaces, Solids, Planes and Vectors 740Positioning Points, Curves, Surfaces, Solids, Planes and Vectors 749Vector Summing (VSum) Points, Curves, Surfaces and Solids 759Moving and Scaling (MScale) Points, Curves, Surfaces and Solids 768

Transforming Coordinate Frames 777Translating Coordinate Frames 777Rotating Coordinate Frames 780

9 Verify Actions

Verify Action 786Verifying Surface Boundaries 786Verifying Surfaces for B-reps 788


viii

Verify - Surface (Duplicates) 790

10 Associate Actions

Overview of the Associate Action 794Associating Point Object 795Associating Curve Object 797

11 Disassociate Actions

Overview of the Disassociate Action Methods 800Disassociating Points 801Disassociating Curves 802Disassociating Surfaces 802

12 The Renumber Action... Renumbering Geometry

Introduction 806

Renumber Forms 807Renumber Geometry 808

Chapter 1: Introduction to Geometry ModelingGeometry Modeling - Reference Manual Part 2

1 Introduction to Geometry Modeling

Overview of Capabilities 2

Concepts and Definitions 4

Types of Geometry in Patran 20

Building An Optimal Geometry Model 31

Geometry Modeling - Reference Manual Part 2Overview of Capabilities

2

Overview of CapabilitiesA powerful and important feature of Patran is its geometry capabilities. Geometry can be:

• Created.

• Directly accessed from an external CAD part file.

• Imported from an IGES file or a PATRAN 2 Neutral file.

Complete Accuracy of Original Geometry

Patran maintains complete accuracy of the original geometry, regardless of where it came from. The exact mathematical representation of the geometry (e.g., Arc, Rational B-Spline, B-rep, Parametric Cubic, etc.) is consistently maintained throughout the modeling process, without any approximations or conversions.

This means different versions of the geometry model are avoided. Only one copy of the geometry design needs to be maintained by the engineer, whether the geometry is in a separate CAD part file or IGES file or the geometry is part of the Patran database.

Below are highlights of the geometry capabilities:

Direct Application of Loads/BCs and Element Properties to Geometry

All loads, boundary conditions (BC) and element property assignments can be applied directly to the geometry. When the geometry is meshed with a set of nodes and elements, Patran will automatically assign the loads/BC or element property to the appropriate nodes or elements.

Although you can apply the loads/BCs or element properties directly to the finite element mesh, the advantage of applying them to the geometry is if you remesh the geometry, they remain associated with the model. Once a new mesh is created, the loads/BC and element properties are automatically reassigned.

For more information, see Introduction to Functional Assignment Tasks (Ch. 1) in the Patran Reference Manual.

Direct Geometry Access

Direct Geometry Access (DGA) is the capability to directly access (or read) geometry information from an external CAD user file, without the use of an intermediate translator. Currently, DGA supports the following CAD systems:

• EDS/Unigraphics

• Pro/ENGINEER by Parametric Technology

• CATIA by Dassault Systemes

With DGA, the CAD geometry and its topology that are contained in the CAD user file can be accessed. Once the geometry is accessed, you can build upon or modify the accessed geometry in Patran, mesh the geometry, and assign the loads/BC and the element properties directly to the geometry.

3Chapter 1: Introduction to Geometry ModelingOverview of Capabilities

For more detailed information on DGA, see Direct Geometry Access of CAD Geometry, 47.

Import and Export of Geometry

There are three file formats available to import or export geometry:

• IGES

• PATRAN 2 Neutral File

• Express Neutral File

In using any of the file formats, Patran maintains the original mathematical form of the geometry. (That is, the geometry is not approximated into the parametric cubic form.) This means the accuracy of the geometry in all three files is maintained.

For more information on the import and export capabilities for IGES, PATRAN 2 Neutral File, and the Express Neutral File, see Accessing, Importing & Exporting Geometry.

Patran Native Geometry

You can also create geometry in Patran (“native” geometry). A large number of methods are available to create, translate, and edit geometry, as well as methods to verify, delete and show information.

Patran’s native geometry consists of:

• Points

• Parametric curves

• Bi-parametric surfaces

• Tri-parametric solids

• Boundary represented (B-rep) solids

All native geometry is fully parameterized both on the outer boundaries and within the interior (except for B-rep solids which are parameterized only on the outer surfaces).

Fully parameterized geometry means that you can apply varying loads or element properties directly to the geometric entity. Patran evaluates the variation at all exterior and interior locations on the geometric entity.

Geometry Modeling - Reference Manual Part 2Concepts and Definitions

4

Concepts and DefinitionsThere are many functions in Patran that rely on the mathematical representation of the geometry. These functions are:

• Applying a pressure load to a curve, surface or solid.

• Creating a field function in parametric space.

• Meshing a curve, surface or solid.

• Referencing a vertex, edge or face of a curve, surface or solid.

For every curve, surface or solid in a user database, information is stored on its Parameterization, Topology and Connectivity which is used in various Patran functions.

The concepts of parameterization, connectivity and topology are easy to understand and they are important to know when building a geometry and an analysis model.

The following sections will describe each of these concepts and how you can build an optimal geometry model for analysis.

ParameterizationAll Patran geometry are labeled one of the following:

• Point (0-Dimensions)

• Curve (1-Dimension)

• Surface (2-Dimensions)

• Solid (3-Dimensions)

Depending on the order of the entity - whether it is a one-dimensional curve, a two-dimensional surface, or a three-dimensional solid - there is one, two or three parameters labeled , , that are associated

with the entity. This concept is called “parameterization”.

Parameterization means the X,Y,Z coordinates of a curve, surface or solid are represented as functions of variables or parameters. Depending on the dimension of the entity, the X,Y,Z locations are functions of the parameters , , and .

An analogy to the parameterization of geometry is describing an , location as a function of time, t.

If and , as changes, and will define a path. Parameterization of geometry

does the same thing - as the parameters , , and change, it defines various points on the curve,

surface and solid.

The following describes how a point, curve, surface and solid are parameterized in Patran.

Point

A Point in Patran is a point coordinate location in three-dimensional global XYZ space.

1 2 3

1 2 3

X Y t

X X t = Y Y t = t X Y

1 2 3

5Chapter 1: Introduction to Geometry ModelingConcepts and Definitions

Since a point has zero-dimensions, it has no associated parameters, therefore, it is not parameterized.

Figure 1-1 Point in Patran

Curve

A Curve in Patran is a one-dimensional point set in three-dimensional global XYZ space. A curve can also be described as a particle moving along a defined path in space.

Another way of defining a curve is, a curve is a mapping function, , from one-dimensional

parametric space into three-dimensional global XYZ space, as shown in Figure 1-3.

A curve has one parametric variable, , which is used to describe the location of any given point, ,

along a curve, as shown in Figure 1-2.

Figure 1-2 Curve in Patran

The parameter, , has a range of , where at , is at endpoint and at , is at

endpoint .

1

1 P

1 0 1 1 1 0= P V1 1 1= P

V2


6

A straight curve can be defined as:

(1-1)

Figure 1-3 Mapping Function Phi for a Curve

(1-1) of our straight curve can be represented as:

(1-2)

The derivative of in (1-2), would give us (1-3) which is the tangent of the straight curve.

(1-3)

Because the curve is straight, is a constant value. The tangent, , also defines a vector for

the curve, which is the positive direction of .

For any given curve, the tangent and positive direction of at any point along the curve can be found.

(The vector, , usually will not have a length of one.)

Surface

A surface in Patran is a two-dimensional point set in three-dimensional global XYZ space.

A surface has two parameters, and , where at any given point, , on the surface, can be located

by and , as shown in Figure 1-4.

P 1.0 1– V1 1V2+=

1 1.0 1– V1 1V2+=

1

1 V2 V1–=

1 1

1

1

1

1 2 P P

1 2


Figure 1-4 Surface in Patran

A surface generally has three or four edges. Trimmed surfaces can have more than four edges. For more information, see Trimmed Surfaces, 20.

Similar to a curve, and for a surface have ranges of and . Thus, at ,

, is at and at , , is at .

A surface is represented by a mapping function, , which maps the parametric space into the

global XYZ space, as shown in Figure 1-5.

1 2 0 1 1 0 2 1 1 0=

2 0= P V1 1 1= 2 1= P V3

1 , 2


8

import a B-rep See B-rep Solid,

Figure 1-5 Mapping Function Phi for a Surface

The first order derivatives of results in two partial derivatives, and :

(1-4)

where is the tangent vector in the direction and is the tangent vector in the direction.

At any point for a given surface, and which define the tangents and the positive and

directions can be determined.

Usually and are not orthonormal, which means they do not have a length of one and they are not

perpendicular to each other.

Solid

A solid in Patran is a three-dimensional point set in three-dimensional global XYZ space.

A solid has three parameters, , , and , where at any given point, , within the solid, can be

located by , , and , as shown in Figure 1-6.

1 , 2 1 2

1 T1 and 2 T2==

T1 1 T2 2

T1 T2 1 2

T1 T2

1 2 3 P P

1 2 3

Note: Note: The above definition applies to tri-parametric solids only. Patran can also create orsolid, which is parameterized on the outer surface only, and not within the interior.for more information.


Figure 1-6 Solid in Patran

A solid generally has five or six sides or faces. (A B-rep solid can have more than six faces.)

The parameters , and have ranges of , , and . At (0,0,0) is at

and at (1,1,1), is at .

A solid can be represented by a mapping function, , which maps the parametric space into the

global XYZ space, as shown in Figure 1-7.

1 2 3 0 1 1 0 2 1 0 3 1 P V1

P V7

1 , 2 3,


10

Figure 1-7 Mapping Function Phi for a Solid

If we take the first order derivatives of , we get three partial derivatives, , and

, shown in (1-5):

(1-5)

Where is the tangent vector in the direction, is the tangent vector in the direction, and

is the tangent vector in the direction.

At any point within a given solid, , and , which define the tangents and positive , and

directions can be determined.

TopologyTopology identifies the kinds of items used to define adjacency relationships between geometric entities.

Every curve, surface and solid in Patran has a defined set of topologic entities. You can reference these entities when you build the geometry or analysis model. Examples of this include:

• Creating a surface between edges of two surfaces.

1 , 2 3, 1 2

3

1 T1 , 2 T2, 3 T3===

T1 1 T2 2 T3

3

T1 T2 T3 1 2 3


• Meshing an edge or a face of a solid.

• Referencing a vertex of a curve, surface or solid to apply a loads/BC.

Topology is invariant through a one-to-one bicontinuous mapping transformation. This means you can have two curves, surfaces or solids that have different parameterizations, but topologically, they can be identical.

To illustrate this concept, Figure 1-8 shows three groups of surfaces A-D. Geometrically, they are different, but topologically they are the same.

Figure 1-8 Topologically Equivalent Surfaces

Topologic Entities: Vertex, Edge, Face, Body

The types of topologic entities found in Patran are the following:


12

Vertex, Edge and Face ID Assignments in Patran

The connectivity for a curve, surface and solid determines the order in which the internal vertex, edge and face IDs will be assigned. The location of a geometric entity’s parametric axes defines the point where assignment of the IDs for the entity’s vertices, edges and faces will begin.

Figure 1-9 and Figure 1-10 show a four sided surface and a six sided solid with the internal vertex, edge and face IDs displayed. If the connectivity changes, then the IDs of the vertices, edges and faces will also change.

Figure 1-9 Vertex & Edge Numbering for a Surface

Vertex Defines the topologic endpoint of a curve, or a corner of a surface or a solid. A vertex is separate from a geometric point, although a point can exist on a vertex.

Edge Defines the topologic curve on a surface or a solid. An edge is separate from a geometric curve, although a curve can exist on an edge.

Face Defines the topologic surface of a solid. A face is separate from a geometric surface, although a surface can exist on a face.

Body A group of surfaces that forms a closed volume. A body is usually referenced as a B-rep solid or a Volume solid, where only its exterior surfaces are parameterized. See Solids, 24 for more information.

Important:Generally, when modeling in Patran, you do not need to know the topologic entities’ internal IDs. When you cursor select a topologic entity, such as an edge of a surface, the ID will be displayed in the appropriate listbox on the form.


Figure 1-10 Face Numbering for a Solid

For example, in Figure 1-9, the edge, ED3, of Surface 11 would be displayed as:

Surface 11.3

The vertex, V4, in Figure 1-9 would be displayed as:

Surface 11.3.1

V4 has a vertex ID of 1 that belongs to edge 3 on surface 11.

The face, F1, of Solid 100 in Figure 1-9 would be displayed as:

Solid 100.1

The edge, ED10, in Figure 1-10 would be displayed as:

Solid 100.1.3

ED10 has an edge ID of 3 that belongs to face 1 on solid 100.

The vertex, V6, in Figure 1-10 would be displayed as:

Solid 100.1.2.2

V6 has a vertex ID of 2 that belongs to edge 2 on face 1 on solid 100.

Topological Congruency and Meshing

When meshing adjacent surfaces or solids, Patran requires the geometry be topologically congruent so that coincident nodes will be created along the common boundaries.


14

Figure 1-11 shows an example where surfaces 1 through 3 are topologically incongruent and surfaces 2 through 5 are topologically congruent. The outer vertices are shared for surfaces 1 through 3, but the inside edges are not. Surfaces 2 through 5 all have common edges, as well as common vertices.

There are several ways to correct surfaces 1 through 3 to make them congruent. See Building a Congruent Model for more information.

Figure 1-11 Topologically Incongruent and Congruent Surfaces

For a group of surfaces or solids to be congruent, the adjacent surfaces or solids must share common edges, as well as common vertices.

(MSC.Software Corporation’s Patran software product required adjacent surfaces or solids to share only the common vertices to be considered topologically congruent for meshing.)

Gaps Between Adjacent Surfaces

Another type of topological incongruence is shown in Figure 1-12. It shows a gap between two pairs of surfaces that is greater than the Global Model Tolerance. This means when you mesh the surface pairs, coincident nodes will not be created along both sides of the gap.


Figure 1-12 Topologically Incongruent Surfaces with a Gap

MSC recommends two methods for closing surface gaps:

• Use the Create/Surface/Match form. See Matching Adjacent Surfaces.

• Use the Edit/Surface/Edge Match form. See Matching Surface Edges.

For more information on meshing, see Introduction to Functional Assignment Tasks (Ch. 1) in the Patran Reference Manual.

Non-manifold Topology

Non-manifold topology can be simply defined as a geometry that is non-manufacturable. However, in analysis, non-manifold topology is sometimes either necessary or desirable. Figure 1-13 shows a surface model with a non-manifold edge.


16

Figure 1-13 Non-manifold Topology at an Edge

This case may be perfectly fine. A non-manifold edge has more than two surfaces or solid faces connected to it. Therefore, two solids which share a common face also give non-manifold geometry (both the common face and its edges are non-manifold).

In general, non-manifold topology is acceptable in Patran. The exception is in the creation of a B-rep solid where a non-manifold edge is not allowed. The Verifying Surface Boundaries option detects non-manifold edges as well as free edges.

ConnectivityIn Figure 1-2, Figure 1-4, and Figure 1-6 in Parameterization, the axes for the parameters, , , and ,

have a unique orientation and location on the curve, surface and solid.

Depending on the orientation and location of the , , and axes, this defines a unique connectivity

for the curve, surface or solid.

For example, although the following two curves are identical, the connectivity is different for each curve (note that the vertex IDs are reversed):

1 2 3

1 2 3


Figure 1-14 Connectivity Possibilities for a Curve

For a four sided surface, there are a total of eight possible connectivity definitions. Two possible connectivities are shown in Figure 1-15. (Again, notice that the vertex and edge IDs are different for each surface.)

Figure 1-15 Two Possible Connectivities for a Surface

For a tri-parametric solid with six faces, there are a total of 24 possible connectivity definitions in Patran - three orientations at each of the eight vertices. Two possible connectivities are shown in Figure 1-16.

Figure 1-16 Two Possible Connectivities for a Solid


18

Plotting the Parametric Axes

Patran can plot the location and orientation of the parametric axes for the geometric entities by turning on the Parametric Direction toggle on the Geometric Properties form, under the Display/Display Properties/Geometric menu. See Preferences>Geometry (p. 467) in the Patran Reference Manual for more information.

Modifying the Connectivity

For most geometric entities, you can modify the connectivity by altering the orientation and/or location of the parametric axes by using the Geometry application’s Edit action’s Reverse method. See Overview of the Edit Action Methods.

For solids, you can also control the location of the parametric origin under the Preferences/Geometry menu and choose either the Patran Convention button or the PATRAN 2.5 Convention button for the Solid Origin Location.

Effects of Parameterization, Connectivity and Topology in PatranThe geometry’s parameterization and connectivity affect the geometry and finite element analysis model in the following ways:

Defines Order of Internal Topologic IDs

The parameterization and connectivity for a curve, surface or solid define the order of the internal IDs of their topologic entities. Patran stores these IDs internally and displays them when you cursor select a vertex, edge or face. See Vertex, Edge and Face ID Assignments in Patran for more information.

Defines Positive Surface Normals

Using right hand rule by crossing a surface’s direction with its direction, it defines the surface’s

positive normal direction ( direction). This affects many areas of geometry and finite element creation,

including creating B-rep solids. See Building An Optimal Geometry Model for more information.

Defines Positive Pressure Load Directions

The parameterization and connectivity of a curve, surface or solid define the positive direction for a pressure load, and it defines the surface’s top and bottom locations for an element variable pressure load. See Create Structural LBCs Sets (p. 27) in the Patran Reference Manual for more information.

Helps Define Parametric Field Functions

If you reference a field function that was defined in parametric space, when creating a varying loads/BC or a varying element or material property, the loads/BC values or the property values will depend on the geometry’s parameterization and the orientation of the parametric axes. See Fields Forms (p. 210) in the Patran Reference Manual for more information.

1 2

3


Defines Node and Element ID Order For IsoMesh

The Patran mapped mesher, IsoMesh, will use the geometric entity’s parameterization and connectivity to define the order of the node and element IDs and the element connectivity. (The parameterization and connectivity will not be used if the mesh will have a transition or change in the number of elements within the surface or solid.) See IsoMesh (p. 13) in the Reference Manual - Part III for more information.

Global Model Tolerance & GeometryPatran uses the Global Model Tolerance when it imports or accesses geometry, when it creates geometry, or when it modifies existing geometry.

The Global Model Tolerance is found under the Preferences/Global menu. The default value is 0.005.

When creating geometry, if two points are within a distance of the Global Model Tolerance, then Patran will only create the first point and not the second.

This rule also applies to curves, surfaces and solids. If the points that describe two curves, surfaces or solids are within a distance of the Global Model Tolerance, then only the first curve, surface or solid will be created, and not the second.

For more information on the Global Model Tolerance, see (p. 72) in the Patran Reference Manual.

Important:For models with dimensions which vary significantly from 10 units, MSC recommends you set the Global Model Tolerance to .05% of the maximum model dimension.

Geometry Modeling - Reference Manual Part 2Types of Geometry in Patran

20

Types of Geometry in PatranGenerally, there are four types of geometry objects in Patran:1

• Point (default color is cyan)

• Parametric Curve (default color is yellow)

• Bi-Parametric Surface (default color is green)

• Tri-Parametric Solid (default color is dark blue)

Patran also can access, import, and create Trimmed Surfaces, B-rep Solids and Volume Solids. See Trimmed Surfaces and Solids for more information.

You also can create parametric cubic curves, surfaces and solids, which are recognized by the PATRAN 2 neutral file. See Parametric Cubic Geometry for more information.

For more information on the types of geometry that can be created, see Matrix of Geometry Types Created.

Trimmed SurfacesTrimmed surfaces are a special class of bi-parametric surfaces. Trimmed surfaces can be accessed from an external CAD user file; they can be imported from an IGES or Express Neutral file; and they can be created in Patran.

Unlike other types of bi-parametric surfaces, trimmed surfaces can have more than four edges, and they can have one or more interior holes or cutouts.

Also, trimmed surfaces have an associated parent surface that is not displayed. A trimmed surface is defined by identifying the closed active and inactive regions of the parent surface. This parent surface defines the parameterization and curvature of the trimmed surface.

You can create three types of trimmed surfaces in Patran:2

• General Trimmed Surface (default color is magenta)

• Simply Trimmed Surface (default color is green)

• Composite Trimmed Surface (default is magenta)

• Ordinary Composite Trimmed Surface (default color is green)

(Green is the default color for both a simply trimmed surface and a general, bi-parametric surface.)

1The default colors are used if the Display Method is set to Entity Type, instead of Group, on the Graphics Preferences form under the Preferences/Graphics menu.


21Chapter 1: Introduction to Geometry ModelingTypes of Geometry in Patran

General Trimmed Surface

A general trimmed surface can have any number of outer edges and any number of inner edges which describe holes or cutouts. These outer and inner edges are defined by a closed loop of chained curves. (Chained curves can be created with the Create/Curve/Chain form. See Creating Chained Curves.) An example is shown in Figure 1-17.

All general trimmed surfaces, whether they are accessed, imported or created, have a default color of

magenta.1

Figure 1-17 General Trimmed Surface

Important:Simply trimmed surfaces and ordinary composite trimmed surfaces can be meshed with IsoMesh or Paver. General trimmed surfaces and composite trimmed surfaces can only be meshed with Paver. See Meshing Surfaces with IsoMesh or Paver (p. 13) in the Reference Manual - Part III for more information. Also note that some geometric operations are not currently possible with a general trimmed surface, e.g., a general trimmed surface can not be used to create a triparametric solid.



22

Simply Trimmed Surface

A simply trimmed surface can only have four outer edges. It cannot have any inner edges, or holes or cutouts. A simply trimmed surface reparametrizes the bounded region of the parent and is called an overparametrization. An example is shown in Figure 1-18. (A simply trimmed surface can have three sides, with one of the four edges degenerating to a zero length edge.)

Like a general trimmed surface, a simply trimmed surface’s outer edges are defined by a closed loop of chained curves. See Creating Chained Curves.

All simply trimmed surfaces, whether they are accessed, imported or created, have a default color of

green. 1

Figure 1-18 Simply Trimmed Surface

Sometimes a three of four sided region which define a trimmed surface will be created as a general trimmed surface instead. This occurs when the overparametrization distorts the bounded region of the parent to such an extent that it would be difficult to mesh and use for analysis.

Composite Trimmed Surface

The composite trimmed surface is a kind of supervisor surface that allows a collection of surfaces to be considered as one surface defined within a specific boundary. This surface can also have holes in it. Evaluations on the composite trimmed surface is similar to evaluations on the Patran trim surface



(General Trimmed Surface). The big difference is that it is three to five times slower than ordinary surfaces.

The composite trimmed surface should be considered a tool. Once the surface is built, it is a single entity, yet processes on multiple surfaces, relieving the applications of the task of determining where and when to move from one surface to another.

APPLICATION: The composite trimmed surface supervisor is a bounded PLANAR trim surface. It acquires its name from the type of service it performs. Let us, for a moment, consider the composite trimmed surface to be a cloud in the sky. The sun, being the light source behind the cloud, creating a shadow on planet earth only in the area blocked by the cloud. The same is true with the composite trimmed surface, except a view vector is given to determine the light direction. “Under Surfaces” replace planet earth. The valid region on the “Under Surfaces” is defined by where the outline of the composite trimmed surface appears.

STEPS_BUILDING: There are three basic steps in building a composite trimmed surface.

RULES:

1. The composite trimmed surface domain must not encompass any dead space. If any portion has a vacancy (no “Under Surface” under it), unpredictable results will occur.

2. Processing along the view vector must yield a single intersection solution at any position on the underlying surfaces within the composite trimmed surface’s domain.

Step 1 Creating the outer perimeter curve. In most cases this is a Patran curve chain entity.

Step 2 Selecting an acceptable view direction for the view vector and planar Composite trimmed surface entity. The view vector is the most important aspect of building a composite trimmed surface. The resulting view vector must yield only one intersection solution at any position on the “Under Surfaces”. The user must select the proper view for the location of the composite trimmed surface with some forethought and eliminate the possibility of any of the underlying surfaces wrapping around in back of one another. In some cases this may not be possible! The user must then create more than one composite trimmed surface.

Additionally, since the composite trimmed surface supervisor is PLANAR, it cannot encompass more than a 180 degree field of view. An example of this would be a cylindrically shaped group of surfaces. It would probably take three properly placed composite trimmed surface to represent it; one for every 120 degrees of

rotation.Step 3 Determines which currently displayed surfaces will be become part of the

composite trimmed surface domain (“Under Surfaces”). The user may individually select the correct underlying surfaces or, if wanting to select all visible surfaces, the user must place into “ERASE” all surfaces which might cause multiple intersections and then select the remaining visible surfaces.


24

Ordinary Composite Trimmed Surface

The only difference between an Ordinary Composite Trimmed Surface and the Composite Trimmed Surface is that this type will have only four edges comprising the outer loop and no inner loops.

Solids

There are three types of solids that can be accessed or imported, or created in Patran:1

• Tri-Parametric Solid (default color is dark blue)

• B-rep Solid (default color is white)

• Volume Solid (default color is pink or light red)

on (p. 2) lists the types of solids created with each Geometry Application method.

Tri-Parametric Solid

All solids in Patran, except for B-rep solids and volume solids, are tri-parametric solids. Tri-parametric solids are parameterized on the surface, as well as inside the solid. Tri-parametric solids can only have four to six faces with no interior voids or holes.

Tri-parametric solids can be meshed with IsoMesh or TetMesh.

B-rep Solid

A B-rep solid is formed from a group of topologically congruent surfaces that define a completely closed volume. Only its outer surfaces or faces are parameterized and not the interior. An example is shown in Figure 1-19.

The group of surfaces that define the B-rep solid are its shell. A B-rep shell defines the exterior of the solid, as well as any interior voids or holes. Shells can be composed of bi-parametric surfaces and/or trimmed surfaces.

B-rep solids can be created with the Create/Solid/B-rep form. See Creating a Boundary Representation (B-rep) Solid on using the form.


Note: IsoMesh will create hexagonal elements if the solid has five or six faces, but some wedge elements will be created for the five faced solid. IsoMesh will create a tetrahedron mesh for a four faced solid. See Meshing Solids (p. 14) in the Reference Manual - Part III.


Figure 1-19 B-rep Solid in Patran

B-rep solids are meshed with TetMesh. See Meshing Solids (p. 14) in the Reference Manual - Part III for more information.

Parametric Cubic GeometryParametric cubic geometry is a special class of parameterized geometry. Parametric cubic geometry is supported in Patran by the PATRAN 2 neutral file and the IGES file for import and export.

You have the option to create parametric cubic curves, bi-parametric cubic surfaces and tri-parametric cubic solids, by pressing the PATRAN 2 Convention button found on most Geometry application forms.

Parametric cubic geometry can also be created in Patran, which are referred to as “grids”, “lines”, “patches” and “hyperpatches.”

Parametric cubic geometry is defined by a parametric cubic equation. For example, a parametric cubic curve is represented by the following cubic equation:

(1-6)

where represents the general coordinate of the global coordinates X,Y, and Z; , , , and

are arbitrary constants; and is a parameter in the range of .

For more information on parametric cubic geometry, see Patran Reference Manual.

Note: Unless you intend to export the geometry using the PATRAN 2 neutral file, in most situations, you do not need to press the PATRAN 2 Convention button to create parametric cubic geometry.

Z 1 S113

= S212

S31 S4+ + +

Z 1 S1 S2 S3 S4

1 0 1 1


26

Limitations on Parametric Cubic Geometry

There are some limitations on parametric cubic geometry.

Limits on Types of Curvature

There are limits to the types of curvature or shapes that are allowed for a parametric cubic curve, surface or solid (see Figure 1-20).

(1-7) and (1-8) below represent the first and second derivatives of (1-6):

(1-7)

(1-8)

(1-7) shows that a parametric cubic curve can only have two points with zero slope and (1-8) shows that it can only have one point of inflection, as shown in Figure 1-20.

Figure 1-20 Limitations of the Parametric Cubic Curvature

Limits on Accuracy of Subtended Arcs

When you subtend an arc using a parametric cubic curve, surface or solid, the difference between the true arc radius and the arc radius calculated by the parametric cubic equation will increase. That is, as the angle of a subtended arc for a parametric cubic entity increases, the accuracy of the entity from the true representation of the arc decreases.

Figure 1-21 shows that as the subtended angle of a parametric cubic entity increases, the percent error also increases substantially beyond 75 degrees.

When creating arcs with parametric cubic geometry, MSC recommends using Figure 1-21 to determine the maximum arc length and its percent error that is acceptable to you.

For example, if you create an arc length of 90 degrees, it will have an error of 0.0275% from the true arc length.

Z 1 3S112

= 2S21 S3+ +

Z 1 6S11= 2S2+


For most geometry models, MSC recommends arc lengths represented by parametric cubic geometry should be 90 degrees or less. For a more accurate model, the parametric cubic arc lengths should be 30 degrees or less.

Figure 1-21 Maximum Percent Error for Parametric Cubic Arc

Matrix of Geometry Types CreatedAll Geometry Application forms use the following Object menu terms:

• Point

• Curve

• Surface

• Solid

• Plane

• Vector

• Coordinate Frame

Patran will create a specific geometric type of the parametric curve, bi-parametric surface and tri-parametric solid based on the method used for the Create action or Edit action.

Table 1-1, and list the types of geometry created for each Create or Edit action method. The tables also list if each method can create parametric cubic curves, surfaces or solids by pressing the PATRAN 2


28

Convention button on the application form. (Parametric cubic geometry is recognized by the PATRAN 2 neutral file for export.)

For more information on each Create or Edit action method, see Overview of Geometry Create Action and/or Overview of the Edit Action Methods.

Table 1-1 Types of Curves Created in Patran

Create or Edit Method Type of Curve

PATRAN 2 Convention?

(Parametric Cubic)

XYZ Parametric Cubic Not Applicable

Arc3Point Arc Yes

2D Arc2Point Arc Yes

2D Arc3Point Arc Yes

2D Circle Circle Yes

Conic Parametric Cubic N/A

Extract Curve On Surface Yes

Fillet Parametric Cubic N/A

Fit Parametric Cubic N/A

Intersect PieceWise Cubic Polynomial Yes

Involute Parametric Cubic N/A

Normal Parametric Cubic N/A

2D Normal Parametric Cubic N/A

2D ArcAngles Arc Yes

Point Parametric Cubic N/A

Project Curve On Surface Yes

PWL Parametric Cubic N/A

Revolve Arc Yes

Spline, Loft Spline option PieceWise Cubic Polynomial Yes

Spline, B-Spline option PieceWise Rational Polynomial Yes

Spline, B-Spline option NURB* Yes

TanCurve Parametric Cubic N/A

TanPoint Parametric Cubic N/A

Chain Composite Curve No

Manifold Curve On Surface Yes


*NURB splines are created if the NURBS Accelerator toggle is pressed OFF (default is ON) on the Geometry Preferences form, found under the Preferences/Geometry menu. This is true whether you create the spline in Patran or if you import the spline from an IGES file. See Preferences>Geometry (p. 467) in the Patran Reference Manual for more information. If the NURBS Accelerator is ON, PieceWise Rational Polynomial splines will be created instead.

Table 1-2 Types of Surfaces Created in Patran

Create or Edit Method Type of Surface


(Parametric Cubic)

XYZ Parametric Bi-Cubic Not Applicable

Curve Curve Interpolating Surface Yes

Decompose Trimmed Surface Yes

Edge Generalized Coons Surface Yes

Extract Surface On Solid Yes

Extrude Extruded Surface Yes

Fillet Parametric Bi-Cubic N/A

Glide Parametric Bi-Cubic N/A

Match Parametric Bi-Cubic N/A

Normal Sweep Normal Surface N/A

Revolve Surface of Revolution Yes

bordered Ruled Surface No

Vertex Curve Interpolating Surface Yes

Trimmed (Surface Option) Trimmed Surface No

Trimmed (Planar Option) Trimmed Surface No

Trimmed (Composite Option) Composite Trimmed Surface No

Table 1-3 Types of Solids Created in Patran

Create or Edit Method Type of Solid


(Parametric Cubic)

XYZ Parametric Tri-Cubic Not Applicable

Extrude Extruded Solid Yes

Face Solid 5Face, Solid 6Face Yes

Glide Glide Solid Yes

Normal Sweep Normal Solid Yes


30

Revolve Solid of Revolution Yes

Surface Surface Interpolating Solid Yes

Vertex Parametric Tri-Cubic N/A

B-rep Ordinary Body No

Decompose Tri-Parametric Yes

Table 1-3 Types of Solids Created in Patran

Create or Edit Method Type of Solid


(Parametric Cubic)

31Chapter 1: Introduction to Geometry ModelingBuilding An Optimal Geometry Model

Building An Optimal Geometry ModelA well defined geometry model simplifies the building of the optimal finite element analysis model. A poorly defined geometry model complicates, or in some situations, makes it impossible to build or complete the analysis model.

In computer aided engineering (CAE) analysis, most geometry models do not consist of neatly trimmed, planar surfaces or solids. In some situations, you may need to modify the geometry to build a congruent model, create a set of degenerate surfaces or solids, or decompose a trimmed surface or B-rep solid.

The following sections will explain how to:

• Build a congruent model.

• Verify and align surface normals.

• Build trimmed surfaces.

• Decompose trimmed surfaces into three- or four-sided surfaces.

• Build a B-rep solid.

• Build degenerate surfaces or solids.

Building a Congruent ModelPatran requires adjacent surfaces or solids be topologically congruent so that the nodes will be coincident at the common boundaries. See Topological Congruency and Meshing for more information.

For example, Figure 1-22 shows surfaces 1, 2 and 3 which are incongruent. When meshing with Isomesh or Paver, Patran cannot guarantee the nodes will coincide at the edges shared by surfaces 1, 2 and 3.

Figure 1-22 Incongruent Set of Surfaces

To make the surfaces in Figure 1-22 congruent, you can:

Geometry Modeling - Reference Manual Part 2Building An Optimal Geometry Model

32

• Use the Edit/Surface/Edge Match form with the Surface-Point option. See Matching Surface Edges on using the form.

• Or, break surface 1 with the Edit/Surface/Break form. See Surface Break Options on using the form.

The following describes the method of using the Edit/Surface/Break form.

To make surfaces 1 through 3 congruent, we will break surface 1 into surfaces 4 and 5, as shown in Figure 1-23:

Figure 1-23 Congruent Set of Surfaces

The entries for the Edit/Surface/Break form are shown below:


Since Auto Execute is ON, we do not need to press the Apply button to execute the form.

Figure 1-24 Cursor Locations for Surface Break

Building Optimal SurfacesBuilding optimal surfaces will save time and it will result in a better idealized finite element analysis model of the design or mechanical part.

Optimal surfaces consist of a good overall shape with no sharp corners, and whose normal is aligned in the same direction with the other surfaces in the model.

u Geometry

Action: Edit

Object: Surface

Method: Break

Option: Point

Delete Original Surfaces

Pressing this button will delete surface 1, after the break.

Surface List: Surface 1 Cursor select or enter the ID for surface 1.

Break Point List Point 10 Cursor select or enter the ID for point 10, as shown in Figure 1-24.


34

Avoiding Sharp Corners

In general, MSC.Software Corporation (MSC) recommends that you avoid sharp inside corners when creating surfaces. That is, you should generally try to keep the inside corners of the surfaces to 45 degrees or more.

The reason is that when you mesh surfaces with quadrilateral elements, the shapes of the elements are determined by the overall shape of the surface, see Figure 1-25. The more skewed the quadrilateral elements are, the less reasonable your analysis results might be.

For further recommendations, please consult the vendor documentation for your finite element analysis code.

Figure 1-25 Surfaces With and Without Sharp Corners

Verifying and Aligning Surface Normals Using Edit/Surface/Reverse

Patran can determine the positive normal direction for each surface by using right hand rule and crossing the parametric and axes of a surface. Depending on the surface’s connectivity, each surface could

have different normal directions, as shown in Figure 1-26.

Note: You can use the surface display lines to predict what the surface element shapes will look like before meshing. You can increase or decrease the number of display lines under the menus Display/Display Properties/Geometric. See Display>Geometry (p. 385) in the Patran Reference Manual.

1 2


Figure 1-26 Opposing Normals for Two Surfaces

The normal direction of a surface affects finite element applications, such defining the positive pressure load direction, the top and bottom surface locations for a variable pressure load, and the element connectivity.

Use the Edit/Surface/Reverse form to display the surface normal vectors, and to reverse or align the normals for a group of surfaces. See Reversing Surfaces on using the form.

Example of Verifying and Aligning Surface Normals

For example, Figure 1-27 shows a group of eight surfaces that we want to display the normal vectors, and if necessary, reverse or align the normals. To display the surface normals without reversing, do the following:

Important:In general, you should try to maintain the same normal direction for all surfaces in a model.


36

Figure 1-27 Group of Surfaces to Verify Normals

You should see red arrows drawn on each surface which represent the surface normal vectors, as shown in Figure 1-28.

u Geometry

Action: Edit

Object: Surface

Method: Reverse

Surface List Surface 1:8 Make sure you turn Auto Execute OFF before cursor selecting surfaces 1-8.

And do not press Apply. Apply will reverse the normals.

Draw Normal Vectors


Figure 1-28 Surface Normal Vectors

Align the normals by reversing the normals for surfaces 1 through 4:

Figure 1-29 shows the updated normal directions which are now aligned.

Figure 1-29 Aligned Surface Normal Vectors

Surface List Surface 1:4

-Apply-

Draw Normal Vectors This will plot the updadirections.


38

Decomposing Trimmed SurfacesTrimmed surfaces are preferred for modeling a complex part with many sides. However, there may be areas in your model where you may want to decompose, or break, a trimmed surface into a series of three or four sided surfaces.

One reason is that you want to mesh the surface area with IsoMesh instead of Paver. (IsoMesh can only mesh surfaces that have three or four edges.) Another reason is that you want to create tri-parametric solids from the decomposed three or four sided surfaces and mesh with IsoMesh.

To decompose a trimmed surface, use the Geometry application’s Create/Surface/Decompose form. See Decomposing Trimmed Surfaces, 254 on using the form.

When entered in the Create/Surface/Decompose form, the select menu that appears at the bottom of the screen will show the following icons:

Point/Vertex/Edge Point/Interior Point. This will select a point for decomposing in the order listed. If not point or vertex is found, the point closest to edge will be used or a point will be projected onto the surface.

Use cursor select or directly input an existing point on the surface. If point is not on the surface, it will be projected onto the surface.

Use to cursor select a point location on an edge of a trimmed surface.

Use to cursor select a point location inside a trimmed surface.

Use to cursor select a vertex of a trimmed surface.


Example

Figure 1-30 shows trimmed surface 4 with seven edges. We will decompose surface 4 into four four-sided surfaces.

Figure 1-30 Trimmed Surface to be Decomposed

Our first decomposed surface will be surface 3, as shown in Figure 1-31. The figure shows surface 3 cursor defined by three vertex locations and one point location along an edge. The point locations can be selected in a clockwise or counterclockwise direction.


40

Figure 1-31 Point Locations for Decomposed Surface 4

Figure 1-32 shows the remaining decomposed surfaces 5, 6 and 7 and the select menu icons used to cursor define the surfaces. Again, the point locations can be selected in a clockwise or counterclockwise direction.

Figure 1-32 Point Locations for Decomposed Surfaces 5, 6 and 7


Use Surface Display Lines as a Guide

Generally, the surface display lines are a good guide to where the trimmed surface can be decomposed. MSC recommends increasing the display lines to four or more. The display lines are controlled under the menus Display/Display Properties/Geometric. See Preferences>Geometry (p. 467) in the Patran Reference Manual for more information.

Building B-rep SolidsBoundary represented (B-rep) solids are created by using the Geometry application’s Create/Solid/B-rep form. See Creating a Boundary Representation (B-rep) Solid, 337 for more information on the form.

There are three rules to follow when you create a B-rep solid in Patran:

1. The group of surfaces that will define the B-rep solid must fully enclose a volume.

2. The surfaces must be topologically congruent. That is, the adjacent surfaces must share a common edge.

3. The normal surface directions for the exterior shell must all point outward, as shown in Figure 1-33. That is, the normals must point away from the material of the body. This will be done automatically during creation as long as rules 1 and 26 are satisfied.

B-rep solids created in Patran can only be meshed with TetMesh.

Figure 1-33 Surface Normals for B-rep Solid

Important:At this time, Patran can only create a B-rep solid with an exterior shell, and no interior shells.


42

Building Degenerate Surfaces and SolidsA bi-parametric surface can degenerate from four edges to three edges. A tri-parametric solid can degenerate from six faces to four or five faces (a tetrahedron or a wedge, respectively).

The following describes the best procedures for creating a degenerate triangular surface and a degenerate tetrahedron and a wedge shaped solid.

Building a Degenerate Surface (Triangle)

There are two ways you can create a degenerate, three-sided surface:

• Use the Create/Surface/Edge form with the 3 Edge option. See Creating Surfaces from Edges (Edge Method) on using the form.

• Or, use the Create/Surface/Curve form with the 2 Curve option. See Creating Surfaces Between 2 Curves on using the form.

Figure 1-34 illustrates the method of using the Create/Surface/Curve form with the 2 Curve option. Notice that the apex of the surface is defined by a zero length curve by using the Curve select menu icon shown in Figure 1-34.

Figure 1-34 Creating a Degenerate Surface Using Create/Surface/Curve

Important:IsoMesh will create hexahedron elements only, if the solid has six faces. Some wedge elements will be created for a solid with five faces. IsoMesh will create tetrahedron elements only, for a solid with four faces. TetMesh will create tetrahedron elements only, for all shaped solids.


Building a Degenerate Solid

Four Sided Solid (Tetrahedron)

A four sided (tetrahedron) solid can be created by using the Create/Solid/Surface form with the 2 Surface option, where the starting surface is defined by a point for the apex of the tetrahedron, and the ending surface is an opposing surface or face, as shown in Figure 1-35.

Five Sided Solid (Pentahedron)

A five sided (pentahedron) solid can be created by using:

• The Create/ Solid/Face form with the 5 Face option. See Creating Solids from Faces on using the form.

• The Create/Solid/Surface form with the 2 Surface option. See Creating Solids from Surfaces (Surface Method) on using the form.

Figure 1-36 and Figure 1-37 illustrate using the Create/Solid/Surface form to create the pentahedron and a wedge.

Figure 1-35 Creating a Tetrahedron Using Create/Solid/Surface


44

Figure 1-36 Creating a Pentahedron Using Create/Solid/Surface

Figure 1-37 Creating a Wedge Using Create/Solid/Surface

Chapter 2: Accessing, Importing & Exporting GeometryGeometry Modeling - Reference Manual Part 2

2 Accessing, Importing & Exporting Geometry

Overview 46

Direct Geometry Access of CAD Geometry 47

PATRAN 2 Neutral File Support For Parametric Cubic Geometry 57

Geometry Modeling - Reference Manual Part 2Overview

46

OverviewPatran can access geometry from an external CAD system user file. Geometry can also be imported (or read) from a PATRAN 2 Neutral file or from an IGES file. Patran can export (or write) some or all geometry to an external PATRAN 2 Neutral file or IGES file.

Geometry can be accessed or imported into the user database either by using the File/Import menus or by using the File/CAD Model Access menus on the Patran main form. Geometry can be exported from the database using the File/Export menus.

For more information on executing the File/Import and File/Export forms, see File>Import, 77 and File>Export (p. 196) in the Patran Reference Manual.

For more information on accessing CAD models, see Direct Geometry Access of CAD Geometry, 47.

For more information on import and export support of geometry for the PATRAN 2 Neutral file, see PATRAN 2 Neutral File Support For Parametric Cubic Geometry, 57.

For more information on which IGES entities are supported by Patran for importing and exporting, see IGES Entities Supported for Import, 107 and Geometric Entity Types and their Supported IGES Equivalents (p. 206) in the Patran Reference Manual.

47Chapter 2: Accessing, Importing & Exporting GeometryDirect Geometry Access of CAD Geometry

Direct Geometry Access of CAD GeometryPatran can directly access geometry from an external CAD file for the following CAD systems that are listed in Table 2-1.

This unique Direct Geometry Access (DGA) feature allows you to access the CAD geometry and its topology that are contained in the CAD file. Once the geometry is accessed, you can build upon or modify the accessed geometry in Patran, mesh the geometry, and assign the loads and boundary conditions as well as the element properties directly to the geometry.

You can execute a specific Patran CAD Access module by using the File/Importing Models menus on the main form. See File>Import (p. 77) in the Patran Reference Manual for more information.

For more information on using Patran ProENGINEER, see Importing Pro/ENGINEER Files (p. 138) in the Patran Reference Manual.

For more information on using Patran Unigraphics, see Importing Unigraphics Files (p. 149) in the Patran Reference Manual.

Accessing Geometry Using Patran UnigraphicsIf Patran Unigraphics is licensed at your site, you can access the geometric entities from an external EDS/Unigraphics part file.

Features of Patran Unigraphics

• Unigraphics part file can be accessed in Patran using one of two methods. The first method is express file based import. The second method is direct parasolid transmit file based import. In both cases, Unigraphics geometry is imported and stored in a Patran database.

• Patran uses the original geometry definitions of the accessed entities, without any approximations. Parasolid evaluators are directly used for entities imported via the direct parasolid method.

• CAD Access filters are provided that can be selected based on the defined EDS/Unigraphics entity types, levels, and layers.

Table 2-1 Supported CAD Systems and Their Patran CAD Access Modules

Supported CAD System Patran CAD Access Module *

*Each Patran CAD Access module must be licensed before you can access the appropriate external

CAD file. You can find out which Patran products are currently licensed by pressing the MSC.Software Corporation (MSC) icon on the main form, and then pressing the License button on the form that appears.

EDS/Unigraphics Patran Unigraphics

Pro/ENGINEER by Parametric Technology Patran ProENGINEER

CATIA by Dassault Systemes Patran CATIA

Geometry Modeling - Reference Manual Part 2Direct Geometry Access of CAD Geometry

48

• You can automatically create Patran groups when accessing the geometry based on the defined entity types, levels, or layers.

For more information on using Patran Unigraphics, see Importing Unigraphics Files (p. 149) in the Patran Reference Manual.

Tips For Accessing EDS/Unigraphics Geometry for Express File Based Import

1. When you execute EDS/Unigraphics, make sure the solid to be accessed is topologically congruent with no gaps (see Figure 2-1). For more information, see Topological Congruency and Meshing, 13.

Verify that the edges of the solid’s adjacent faces share the same end points or vertices, and that there are no gaps between the faces.

You can improve Patran Unigraphics’ performance by reducing the number of entities to be processed by using the Entity Type filter on the Patran Import form and unselect or un-highlight all entities of a particular type that you do not want, before you access the part file. For example, you can unselect the entity type, “Bounded-Plane”, to eliminate all bounded plane entities. For the direct parasolid import option, the entity type filter can be used for wire body/sheet body/solid body only.

Put those entities in EDS/Unigraphics that you want to access into specific layers. Then select to only those layers in the Patran Import form before importing the part.

Make sure the Patran Global Model Tolerance is reset to an appropriate value if you will be accessing long thin surfaces and solids with small dimensions (default is 0.005). For example, set the tolerance value so that it is smaller than the smallest edge length (greater than 10.0E-6) in the model. This will improve model usability on some models.

Figure 2-1 Topologically Congruent Surfaces for Patran Unigraphics


Tips For Accessing Parasolid Geometry

This section provides helpful hints and recommendations regarding the usage of Patran as it pertains to Parasolid integration.

Solid Geometry Guidelines

Disassembling Solids

The Edit/Solid/Disassemble function in the Geometry Application can be used to create simply trimmed surfaces (green 4-sided) with one command. This can be a big timesaver if the B-rep Solid is being disassembled to eventually create tri-parametric solids (blue) for Hex meshing. This command will convert all 4-sided B-rep Solid faces into simply trimmed surfaces (green) which then can be used to construct tri-parametric solids.

Solids Break If difficulties are encountered in breaking a solid:

1. First disassemble the original solid (Edit/Solid/Disassemble).

2. Try to reconstruct a new solid using Create/Solid/B-rep. If this is unsuccessful due to gaps between surfaces, use the Edit/Surface/Sew and try again. If a solid is created, continue with the break operation.

3. If steps (a) and (b) were unsuccessful:

• Break the trimmed surfaces from the disassembled solid (step (a)). If this operation is slow, refit the surfaces (Edit/Surface/Refit) before the break operation.

• Create the additional surfaces in the interior required to enclose the individual solid volumes.

• Create the new individual solids using Create/Solid/B-rep. If the B-rep can not be created due to surface gaps, use Edit/Surface/Sew and try again.

Global Model Tolerance

After successful access of Unigraphics geometry via the Parasolid Direct method, the Global Model Tolerance will be set relative to the models geometric characteristics. This tolerance is the recommended tolerance for Patran applications to use for best results.

Solids - Group Transform

Group transform for solids is not supported. For information about transforming solids in pre-release format, see , 50.


50

Meshing Guidelines

Hybrid TetMesher - Global Edge Lengths

The Hybrid tetmesher only accepts global edge lengths for mesh criteria if attempting to directly mesh a solid. If you encounter difficulties, decrease the global edge length.

Hybrid TetMesher - Mesh Control

The Hybrid tetmesher does not write nodes that lie on solid edges into the mesh seed table. This limits the ability of the Hybrid tetmesher to recognize existing meshes. For example, if your requirements are: (1) to match adjacent meshes (i.e., multiple solids); (2) that the mesh be able to recognize a hard curve/point; or (3) to define mesh seed prior to solid meshing, follow these steps:

• Define any desired hard points/curves and mesh seeds.

• Surface mesh the geometry using the paver, creating triangular elements which completely enclose the desired geometric volume.

• Invoke the Hybrid tetmesher, using the previously created triangular elements as input.

Paver If the paver exhibits difficulties meshing some geometry or making congruent meshes:

• Delete any existing mesh on the problematic geometry.

• Perform an Edit/Surface/Refit.

• Do an Edit/Surface/Edge Match if congruency is an issue.

• Mesh again.


PRE-RELEASE CAPABILITY: Solid Geometry Guidelines

Solids - Group

Transform

Group transform for solids is not supported. If a transformed solid is required, consider the following alternatives: (1) Perform the transformation in the native CAD system and then again access the desired geometry in Patran; (2) Enable an environment variable before executing Patran. At the system prompt, type:

setenv P3_UG_ENTITY_FILTER 1

which allows the transformation of Parasolid solid geometry and perform the transformation. If a solid is successfully constructed, continue as planned. If not, either:

• Mesh the original solid and transform the resulting finite element mesh, with the limitation being that element properties and loads/boundary conditions will have to be assigned directly to the finite elements; or

• Try to reconstruct a B-rep solid from the constituent surfaces that result from the transformation, by first using Geometry tools such as Edit/Surface/Sew, Edit/Surface/Edge Match, etc., to reconnect the surfaces and then use Create/Solid/B-rep.

• Initially access the original geometry (Unigraphics only) using the Express Translation method. If a solid is successfully imported, a transformation of the geometry is supported.

Surface/Curve Geometry Guidelines

Surface Congruency Unigraphics does not automatically enforce surface congruency. Typically, CAE applications require congruent meshes; therefore, geometric surfaces must usually be congruent. Accessing geometry through Parasolid simply retrieves the Unigraphics geometry exactly as it is defined; an explicit action must be taken to sew geometric surfaces, otherwise they will not be congruent.

It is recommended that models with surfaces be sewn up in Unigraphics prior to access by Patran. Patran offers the ability to also invoke the Unigraphics surface sew tool; in fact, this is the default operation when accessing Sheet Bodies.

Unigraphics Sew With Verify During Geometry Access

“Unigraphics Sew” and “Verify Boundary” toggles are, by default, ON during import. The Verification entails placement of markers at all incongruent surface edges, thus allowing a user to quickly identify whether the Unigraphics Sew was completely (or partially) successful. The markers may be removed using the Broom icon.


52

Problem Unigraphics Entities From Import

Patran detects three different types of anomalies during Unigraphics part file import:

a) Suspect939 Entities: Sometimes Unigraphics needs to take special actions to convert surfaces from earlier version parts. These surfaces are attributed with “Suspect939.” Although for the most part these surfaces are usable, Unigraphics recommends that these surfaces be replaced. As such, Patran will not attempt to include these surfaces in the Unigraphics sewing, and we recommend that these surfaces be refitted once imported into Patran. You will find these surfaces in a group named, <model_name>_UG_SUSPECT.

b) Invalid Entities: Before importing the Unigraphics model, Patran will check each surface and curve entities to ensure consistency and validity. Occasionally, some entities do not pass the checks. These invalid entities will be excluded from both UG sewing and Patran import. If you see such a message in the invoke window, you should go back to UG to ensure the model is valid. Please reference the next section, Unigraphics Model Checks, 53 for steps to do this check. One recommended way is to refit/reconstruct the surface in Unigraphics and then reimport it into Patran.

If UG sewing is turned on for the Patran import, there is a chance that invalid entities are created by the UG sew. These entities will be brought into Patran and put into a group named, <model_name>_UG_INVALID. As there is no guarantee that entities in this group will work with any applications, we strongly recommend you first commit/save the Patran database and then reconstruct these bodies if possible.

c) Gap Surfaces: Sometimes surfaces, that are degenerate or are/close to being zero area, appear in the model. These surfaces are called “gap surfaces.” If there are any such gap surfaces, they will be in a group named, <model_name>_GAP_SURFACE. Please inspect the imported model and determine if these gap surfaces should be removed from the model.



Unigraphics Model Checks

Unigraphics provides geometry evaluation tools which are extremely useful in judging the quality of a model. Here are some geometry/topology checks Unigraphics can perform and provide results with any UG part: (1) In Unigraphics V13.0, “Info” is available at the top menu bar, under Info/Analysis/Examine Geometry. If you use this on surfaces and any are ill-defined, they will be flagged as “suspect”. (2) In Unigraphics V13.0, Info is available at the top menu bar. To run all checks:

• Use Info->Analysis->Examine Geometry...

• Choose “Set All Checks”, then “OK”.

• Choose “Select All” to check the entire model currently selectable.

• NOTE: Default Distance tolerance is 0.001 units and Default Angle tolerance is 0.5 units.

Patran Surface Sew In addition to accessing the Unigraphics surface sew tool, Patran offers an additional capability to sew surfaces beyond what Unigraphics supports (e.g., resolution of T-edges). If the Unigraphics surface sew does not resolve all incongruences, try using the Patran surface sew as well. This capability can be accessed through Edit/Surface/Sew in the Geometry application. If both the Unigraphics and Patran surface sew tools cannot remove all of the gaps and incongruencies, then two options are available. The first option is to refit all of the surfaces (Edit/Surface/Refit). Sometimes, after this operation, these surfaces can be sewn together (Edit/Surface/Sew).

The other option for sewing the model using Patran surface sewing is to increase the global tolerance in Patran and sew the model again. Changing the global tolerance in Patran is generally not recommended, but in this case may be necessary. The necessity of increasing the global tolerance is determined by checking the incongruent edges of the model (Verify/Surface/Boundary) to see if they share vertices, or by the gap closure operation when gaps cannot be closed between surface since the edge curves are too far apart. The tolerance value should be set to a value just larger than the distance between the vertices to be equivalenced (vertices which should be shared at the ends of incongruent curves), or just larger than the “allowable gap closure tolerance” which is issued by the sewing (or edge match) operation.

(Note that there are cases where sewing will report that gaps exist which are not really gaps. This is because the operation of checking for gaps does not necessarily know about the engineering intent of the model. We suggest that the user check the gaps reported to make sure that they are gaps. Furthermore, we suggest that the global tolerance be increased conservatively, e.g., double the tolerance instead of increasing it by an order of magnitude.)



54

Accessing Geometry Using Patran ProENGINEERIf Patran ProENGINEER is licensed at your site, you can access the geometric entities from an external Pro/ENGINEER part file.

You can execute Patran ProENGINEER either from Patran or from Pro/ENGINEER by doing one of the following:

Refitting Geometry The technique of refitting geometry has been identified as a potentially viable method of removing problematic geometry that prevents subsequent meshing, application of LBC’s, editing, transforming, etc. Edit/Curve/Refit and Edit/Surface/Refit are available under the Geometry application. These functions will more regularly parameterize poorly parameterized geometry (for surfaces, this typically involves those with compound curvature), which can currently lead to difficulties in successfully building CAE models. Congruency and boundary definitions are retained.

Edit/Surface/Refit As previously mentioned, the Edit/Surface/Refit function in the Geometry application can be used to successfully handle problematic Sheet Body geometry. The situations where this applies include:

• Accessing geometry with the Unigraphics Sew option disabled with subsequent attempts to make the surfaces congruent by using Patran’s surface sew, edge match, etc.

• Difficulties rendering, meshing, edge matching, disassembling, transforming, etc.

• Surfaces that result from disassembling solid geometry (i.e., for regioning).

Curves Coincident With Surface and Solid Edges

Wire Bodies coincident with Sheet Body and Solid Body edges are not equivalenced. This is a different behavior from what occurs if the “Express Translation” method is used. If coincident curves are not detected by the user, they may, for example, apply a Loads/Boundary Condition to what they believe is a surface or solid edge, when in fact they are applying it to a curve. To avoid this situation:

• Move all Wire Bodies to a separate group and post only when required.

• If Wire Bodies are accessed, use the new Geometry function Edit/Point/Equivalence to connect the curve and surface/solid vertices.

• Disable access of Wire Bodies and only access when needed.



Executing Patran ProENGINEER From Patran

Execute Patran ProENGINEER from Patran by using the File/Import... menu and make sure the Pro/ENGINEER button is pressed on the Import form. See Importing Pro/ENGINEER Files (p. 138) in the Patran Reference Manual for more information.

Executing Patran ProENGINEER From Pro/ENGINEER

Execute Patran ProENGINEER from Pro/ENGINEER by doing the following:

1. Execute Pro/ENGINEER by entering:

p3_proep3_proe will ask for the command name to run Pro/ENGINEER. Press <CR> if you want to accept the default command pro.

Enter the command name for running Pro/ENGINEER.[pro]?: <cr>Open the Pro/ENGINEER assembly file or part file. Then, select the Pro/ENGINEER menus in the following order:

File

Export

Model

Patran Geom

The Patran menu will list four options:

Filter

Run Patran

Create .db

Create .geo

You can select any one of the above four options.

If Filter is selected:

• A menu appears which allows the user to select:

Datum Points

Datum Curves

Datum Surfaces

Datum Planes

Coordinate System Datums

for output to the intermediated .geo file. (Default = no datum entities).

If Run Patran is selected:

Note: Make sure Patran ProENGINEER has been properly installed by following the instructions in Module and Preference Setup (Ch. 3) in the Patran Installation and Operations Guide


56

• A Patran ProENGINEER intermediate.geo file will be created from the current Pro/ENGINEER object in memory.

• Patran will automatically be executed and a database will be created and opened.

• The Patran ProENGINEER intermediate.geo file containing the Pro/ENGINEER geometry will be loaded into the Patran database, and both Pro/ENGINEER and Patran will remain executing.

If Create .db is selected:

• A Patran ProENGINEER intermediate.geo file will be created from the current Pro/ENGINEER object in memory.

• A batch job will be submitted in background mode that will:

One, execute Patran and create and open a database.

Two, load the.geo file into the Patran database.

And, three, close the database and exit Patran.

If Create .geo is selected, a Patran ProENGINEER intermediate.geo file will be created from the current Pro/ENGINEER object in memory.

For more information on the Patran ProENGINEER intermediate.geo file, see Executing Patran ProENGINEER From Pro/ENGINEER (p3_proe) (p. 147) in the Patran Reference Manual.

57Chapter 2: Accessing, Importing & Exporting GeometryPATRAN 2 Neutral File Support For Parametric Cubic Geometry

PATRAN 2 Neutral File Support For Parametric Cubic GeometryThe PATRAN 2 Neutral file is supported by MSC.Software Corporation’s Patran.

With the PATRAN 2 neutral file, Patran can import or export only parametric cubic geometry by executing the File/Import menus on the main form.

Patran cannot export non-parametric cubic geometry using the PATRAN 2 Neutral file. Instead, you may use export the entire geometry model using the IGES file.

Depending on Geometry application methods used to create the geometry, you may or may not be able to create parametric cubic curves, surfaces or solids. Also, some geometry Create action methods can generate only parametric cubic geometry.

For information on how to import or export a PATRAN 2 Neutral file, see Importing PATRAN 2.5 Neutral Files, 92 and Exporting to a PATRAN 2.5 Neutral File (p. 196) in the Patran Reference Manual.

For the definition of parametric cubic geometry, see Parametric Cubic Geometry.

For information on what types of curves, surfaces and solids you can create in Patran, see Table 1-1, and starting on (p. 28).

For more information on how to export an IGES file, see Exporting to IGES Files (p. 206) in the Patran Reference Manual.

Geometry Modeling - Reference Manual Part 2PATRAN 2 Neutral File Support For Parametric Cubic Geometry

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Chapter 3: Coordinate FramesGeometry Modeling - Reference Manual Part 2

3 Coordinate Frames

Coordinate Frame Definitions 60

Overview of Create Methods For Coordinate Frames 64

Translating or Scaling Geometry Using Curvilinear Coordinate Frames 67

Geometry Modeling - Reference Manual Part 2Coordinate Frame Definitions

60

Coordinate Frame DefinitionsPatran can create and support three types of coordinate frames:

• Rectangular (X,Y,Z)

• Cylindrical (R, Theta, Z)

• Spherical (R, Theta, Phi)

Patran also has a default global rectangular coordinate frame, Coord 0. Coord 0 is the default reference coordinate frame for many application forms (which can be changed to another coordinate frame). Also, Coord 0 cannot be deleted, even if specified.

Each coordinate system defined in Patran has three principal axes. These axes define how spatial locations are determined in that coordinate system, and are internally numbered 1, 2 and 3. The meaning of each principal axis depends on if the coordinate frame is rectangular, cylindrical or spherical.

When a coordinate frame is created, its principal axes and its orientation are displayed at the appropriate location on the model. The ID of the coordinate frame is also displayed at the coordinate frame’s origin.

Rectangular Coordinate Frame

Figure 3-1 shows the principal axes of a rectangular coordinate frame and a point, P, in rectangular space. In a rectangular frame, the principal axes 1, 2 and 3 correspond to the X, Y and Z axes, respectively. Points in space specified in a rectangular coordinate frame are entered in the order: x-coordinate, y-coordinate and z-coordinate.

Important:Coordinate frame angles for the cylindrical and spherical coordinate frames (that is, and ) are expressed in degrees. Special conditions apply when defining

spatial functions in cylindrical or spherical coordinate frames. For more information, see Procedures for Using Fields (p. 195) in the Patran Reference Manual.

61Chapter 3: Coordinate FramesCoordinate Frame Definitions

Figure 3-1 Rectangular Coordinate Frame

Cylindrical Coordinate Frame

Figure 3-2 shows a cylindrical frame in which the principal axes 1, 2 and 3 correspond to the R, T ( ) and Z axes, respectively. Points specified in a cylindrical coordinate frame are entered in the order: radial-coordinate, theta-coordinate and z-coordinate.

Geometry Modeling - Reference Manual Part 2Coordinate Frame Definitions

62

Figure 3-2 Cylindrical Coordinate Frame

Spherical Coordinate Frame

Figure 3-3 shows a spherical frame in which the principal axes 1, 2 and 3 correspond to the R, T ( ) and P ( ) axes, respectively. Points specified in a spherical coordinate frame are entered in the order: radial-coordinate, theta-coordinate, and phi-coordinate.

A node’s local directions (1, 2, 3) can vary according to its position within the spherical coordinate frame. For example:

See Input LBCs Set Data (Static Load Case) (p. 36) in the Patran Reference Manual.

If node lies along R direction, then dir 1 of node is along +R

If node lies along R direction, then dir 2 of node is along -P

If node lies along R direction, then dir 3 of node is along +T

If node lies along T direction, then dir 1 of node is along +T

If node lies along T direction, then dir 2 of node is along -P

If node lies along T direction, then dir 3 of node is along -R

If node lies along P direction, then dir 1 of node is along +P

If node lies along P direction, then dir 2 of node is along +T

If node lies along P direction, then dir 3 of node is along -R

63Chapter 3: Coordinate FramesCoordinate Frame Definitions

Figure 3-3 Spherical Coordinate Frame Definition

Geometry Modeling - Reference Manual Part 2Overview of Create Methods For Coordinate Frames

64

Overview of Create Methods For Coordinate FramesThere are six ways you can create a local rectangular, cylindrical or spherical coordinate frame in Patran. They are listed as separate methods under the Geometry Application’s Create action:

• 3Point

• Axis

• Euler

• Normal

• 2Vector

• View Vector

For more information on using the application forms for the Create methods, see Creating Coordinate Frames.

You can also create coordinate frames using the Transform action’s Translate and Rotate methods. For more information, see Transforming Coordinate Frames.

The following sections briefly discuss the Create methods for coordinate frames.

3 Point Method

Figure 3-4 illustrates using the Create action’s 3 Point method for creating a coordinate frame by specifying three points:

Figure 3-4 Coordinate Frame Creation Using the 3 Point Method

Axis Method

Figure 3-5 illustrates using the Axis method to create a coordinate frame by specifying a point location at the origin, a point location on axis 1, 2, or 3, and a point location on one of the two remaining axes.

65Chapter 3: Coordinate FramesOverview of Create Methods For Coordinate Frames

Figure 3-5 Coordinate Frame Creation Using the Axis Method

Euler Method

The Euler Create action creates a new coordinate frame through three rotations from an existing coordinate frame. Specifically, the following steps are performed in the order shown:

1. Input the reference coordinate frame ID.

1. Enter the point location of the coordinate frame’s origin.

1. Enter the axis and rotation angle for Rotation 1.



The final orientation of the new coordinate frame depends on the order of rotations that are made.

Normal Method

Figure 3-6 illustrates using the Normal method to create a coordinate frame, where its origin is at a point location on a surface. The positive axis 3 direction is normal to the surface by using right-hand rule and crossing the surface’s parametric direction with the direction. The axis 1 direction is along the

surface’s direction and the axis 2 direction is orthogonal to axis 1 and 3.

For more information on the definition of the parametric and axes, see Parameterization.

1 2

1

1 2

Geometry Modeling - Reference Manual Part 2Overview of Create Methods For Coordinate Frames

66

Figure 3-6 Coordinate Frame Creation Using the Normal Method

67Chapter 3: Coordinate FramesTranslating or Scaling Geometry Using Curvilinear Coordinate Frames

Translating or Scaling Geometry Using Curvilinear Coordinate FramesYou can translate or scale geometry in Patran by using the Transform action’s Translate method or Scale method. For information and examples on using either form, see Translating Points, Curves, Surfaces, Solids, Planes and Vectors or Scaling Points, Curves, Surfaces, Solids and Vectors.

On either form, you can choose either the Cartesian in Refer. CF toggle or the Curvilinear in Refer. CF toggle.

If Curvilinear in Refer. CF is chosen, you can specify either an existing cylindrical or spherical coordinate frame as the reference, and the translation vector or the scale factors will be interpreted as R,

, Z for the cylindrical system, and as R, , for the spherical system. (Both the axis and axis are measured in degrees.)

Figure 3-7 throughFigure 3-10 are examples of using the Translate and Scale methods with the Curvilinear in Refer. CF toggle.

Figure 3-7 Translate Method where Surface 1 is Translated <1 90 0> within Cylindrical Coordinate Frame 1

Geometry Modeling - Reference Manual Part 2Translating or Scaling Geometry Using Curvilinear Coordinate Frames

68

Figure 3-8 Scale Method where Curve 1 is Scaled <2 1 1> within Cylindrical Coordinate Frame 1


69Chapter 3: Coordinate FramesTranslating or Scaling Geometry Using Curvilinear Coordinate Frames


Points along the z-axis of a cylindrical coordinate system and at the origin of a spherical coordinate system cannot be transformed uniquely in the (cylindrical) or and (spherical) coordinates respectively. This is due to the fact that there is no unique for points on the z-axis of a cylindrical coordinate system or and coordinates at the origin of a spherical coordinate system. Therefore, in Patran, any point on the z-axis of a cylindrical coordinate system or at the origin of a spherical coordinate system is not transformed.

Geometry Modeling - Reference Manual Part 2Translating or Scaling Geometry Using Curvilinear Coordinate Frames

70

Chapter 4: Create ActionsGeometry Modeling - Reference Manual Part 2

4 Create Actions

Overview of Geometry Create Action 72

Creating Points, Curves, Surfaces and Solids 78

Creating Solid Primitives 311

Feature Recognition (Pre-release) 350

Creating Coordinate Frames 393

Creating Planes 407

Creating Vectors 433

Creating P-Shapes 449

Edit P-Shapes 459

Geometry Modeling - Reference Manual Part 2Overview of Geometry Create Action

72

Overview of Geometry Create ActionSelect any method to obtain detailed help.

Object Method Description

Point • XYZ • Creates points from their cartesian coordinates or from existing nodes or vertices.

• ArcCenter • Creates a point at the center of curvature of the specified curves.

• Extract • Creates points on existing curves at a parametric coordinate location.

• Interpolate • Creates one or more points between two existing point locations that are uniformly or nonuniformly spaced apart.

• Intersect • Creates points at the intersection of any of the following pairs of entities: Curve/Curve, Curve/Surface, Curve/Plane, Vector/Curve, Vector/Surface, Vector/Plane.

• Offset • Creates a point on an existing curve.

• Pierce • Creates a point at the location where a curve intersects or pierces a surface or solid face.

• Project • Creates points from an existing set of points or vertices that are either projected normally or projected through a defined vector or projected through the current view angle, onto an existing surface or solid face.

73Chapter 4: Create ActionsOverview of Geometry Create Action

Curve • Point • Creates curves through two, three or four point locations.

• Arc3Point • Creates arced curves through a starting, middle and ending point locations.

• Chain • Creates a chained composite curve from two or more existing curves. Usually used for creating trimmed surfaces.

• Conic • Creates a conic curve based on a defined altitude and focal point and a starting and ending points.

• Extract • Creates a curve on an existing surface either at a parametric coordinate location or on an edge of the surface.

• Fillet • Creates a fillet curve with a defined radius between two existing curves or edges.

• Fit • Creates a curve that passes through a set of point locations based on a least squares fit.

• Intersect • Creates a curve at the intersection of two surfaces or solid faces.

• Manifold • Creates a curve on a a surface or solid face that is between two or more point locations.

• Normal • Creates a curve that is normal from an existing surface or solid face to a point location.

• Offset • Creates either constant or variable offset curves from an existing curve.



74

Curve (cont.)

• Project • Creates curves from an existing set of curves or edges that is projected onto a surface either normally or from a defined plane or vector or based on the current view angle.

• PWL • Creates contiguous straight curves between two or more point locations.

• Spline • Creates a spline curve that passes through two or more point locations.

• TanCurve • Creates a curve that is tangent between two curves or edges.

• TanPoint • Creates a curve from a point location to a tangent point on a curve.

• XYZ • Creates a curve at a defined origin based on a vector that defines its length and orientation.

• Involute • Creates involute curves either using an Angles option or a Radii option.

• Revolve • Creates curves that are rotated from point locations about a rotation axis for a defined angle.

• 2D Normal • Creates straight curves that are perpendicular to an existing curve or edge and that lies within a defined plane.

• 2D Circle • Creates a circle within a defined plane.

• 2D ArcAngles

• Creates arced curves within a defined 2D plane.

• 2D Arc2Point • Creates an arced curve that lies within a defined plane and that uses a starting, ending and center point locations.

• 2D Arc3Point • Creates an arced curve that lies within a defined plane and that passes through a starting, middle and ending point locations.



Surface • Curve • Creates surfaces that passes through either two, three, four or N curves or edges.

• Composite • Create surfaces that are composed from multiple surfaces.

• Decompose • Creates surfaces from an existing surface (usually a trimmed surface) based on four cursor defined vertices that lie on the existing surface.

• Edge • Creates surfaces from three or four curves or edges.

• Extract • Creates a surface within a solid based on either the parametric coordinate location or on the face of the solid.

• Fillet • Creates a filleted surface with one or two defined radii between two existing surfaces or faces.

• Match • Creates a surface that is topologically congruent with one of the two specified surfaces.

• Offset • Creates constant offset surfaces from an existing surface.

• bordered • Creates a surface that is created between two existing curves or edges.

• Trimmed • Creates a trimmed surface that consist of an outer chained curve loop and optionally, an inner chained curve loop.

Surface (cont.)

• Vertex • Creates a surface from four point locations.

• XYZ • Creates a surface at a defined origin based on a vector that defines its length and orientation.

• Extrude • Creates a surface from an existing curve or edge that is extruded through a vector and is optionally scaled and rotated.

• Glide • Creates a surface that is created from a specified director curve or edge, along one or more base curves or edges.

• Normal • Creates surfaces from existing curves through a defined thickness.

• Revolve • Creates surfaces that are rotated from curves or edges about a rotation axis for a defined angle.

• Mesh • Creates a surface from a congruent 2-D mesh (shell mesh).

• P-Shape • Creates a surface (rectangle, triangle, cyclinder, sphere, six-sided box, quadrilateral, disk, cone, paraboloid, or five-sided box) with user input.



76

Solid • Primitive • Creates a solid (block, cylinder, cone, sphere or torus) with user input a point, length, width, height, and reference coordinate frame. It also provides an option to perform boolean operation with the input target solid using the created block, cylinder, cone, sphere or torus as the tool solid.

• Surface • Creates solids that pass through two, three, four or N surfaces or faces.

• B-rep • Creates a B-rep solid from an existing set of surfaces that form a closed volume.

• Decompose • Creates solids from two opposing solid faces by choosing four vertex locations on each face.

• Face • Creates solids from five or six surfaces or faces.

• Vertex • Creates solids from eight point locations.

• XYZ • Creates a solid at a defined origin based on a vector that defines its length and orientation.

• Extrude • Creates a solid from an existing surface or face that is extruded through a vector and is optionally scaled and rotated.

• Glide • Creates a solid that is created from a specified director curve or edge, along one or more base surfaces or faces.

• Normal • Creates solids from existing surfaces through a defined thickness.

• Revolve • Creates solids that are rotated from surfaces or faces about a rotation axis for a defined angle.

Coord • 3Point • Creates a rectangular, cylindrical or spherical coordinate frame based on defined point locations for its origin, a point on Axis 3 and a point on Plane 1-3.

• Axis • Creates a rectangular, cylindrical or spherical coordinate frame based on point locations that define the original and either points one Axis 1 and 2, Axis 2 and 3, or Axis 3 and 1

• Euler • Creates a rectangular, cylindrical or spherical coordinate frame based on three rotation angles about Axes 1, 2 and 3.

• Normal • Creates a rectangular, cylindrical or spherical coordinate frame whose Axis 3 is normal to a specified surface or solid face, and whose origin is at a point location.



Plane • Vector Normal

• Creates a plane from a specified point as the plane origin and a specified direction as the plane normal.

• Curve Normal

• Creates a plane from a point on or projected onto a specified curve as the plane origin and the curve tangent at that point as the plane normal.

• Interpolate • Creates a plane from the interpolating points on a specified curve as the plane origins and the curve tangents at those points as the plane normals.

• Least Squares • Creates a plane from the least square based on three and more specified non-colinear points.

• Offset • Creates a plane that is parallel to a specified plane with a specified offset distance.

• Surface Tangent

• Creates a plane from a specified point on or projected to a specified surface as the plane origin and the surface normal at that location as the plane normal.

• 3 Points • Creates a plane from three specified non-colinear points. The plane origin is located at the first point.

• Point-Vector • Creates planes at a point and normal to a vector.

Vector • Magnitude • Creates a vector by specifying the vector base point, the vector direction and the vector magnitude of the desired vector.

• Intersect • Creates a vector along the intersecting line of two specified planes. The vector base point is the projection of the first plane origin on that intersecting line.

• Normal • Creates a vector that has the direction parallel to a specified plane and the base point at a specified point on or projected onto that plane.

• Product • Creates a vector that is the cross product of two specified vectors and has its base point located at the base point of the first vector.

• 2 Point • Creates a vector that starts from a specified base point and pointing to a specified tip point.


Geometry Modeling - Reference Manual Part 2Creating Points, Curves, Surfaces and Solids

78

Creating Points, Curves, Surfaces and Solids

Create Points at XYZ Coordinates or Point Locations (XYZ Method)The XYZ method creates points from their cartesian coordinates or at an existing node, vertex or other point location as provided in the Point select menu.

79Chapter 4: Create ActionsCreating Points, Curves, Surfaces and Solids

Tip: More Help

• Select Menu (p. 35) in the Patran Reference Manual

• Topology

• Coordinate Frame Definitions

Point XYZ Method Example

Creates Point 6 using the Create/XYZ method that is located at the global rectangular coordinates X = 10, Y = 5 and Z = 3.125.

Point XYZ Method On a Surface Example

Creates Point 5 using the Create/XYZ/Point select menu icons listed below which locates Point 5 on Surface 1, whose exact location is cursor defined.


80

Point XYZ Method At Nodes Example

Creates Points 1 through 4 using the Create/XYZ/Point select menu icon listed below which locates the points at Nodes 10 through 13.


Point XYZ Method At Screen Location Example

Creates Points 1 through 5 using the Create/XYZ/Point select menu icon listed below which locates Points 1 through 5 by cursor defining them on the screen.


82

Create Point ArcCenterThe ArcCenter method creates a point at the center of curvature of the specified curves which have a non-zero center/radius of curvature.


Tip: More Help:


• Topology

Point ArcCenter Method Example

Creates point 3 using Create/Point/Arc Center which locates point 3 in the center of the arc.


84

Extracting Points

Extracting Points from Curves and Edges

Creates points on an existing set of curves or edges at the parametric coordinate location of the curve

or edge, where has a range of .

1

1 0 1 1


Point Extract Method Example

Creates Point 7 using the Create/Extract method, where the point is located at is equal to 0.75, on

Curve 1. Notice that the curve’s parametric direction arrow is displayed.

1 u


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Point Extract Method Example

Creates Point 5 using the Create/Extract method, where the point is located at is equal to 0.75, on

the edge of Surface 1.

1 u


Extracting Single Points from Surfaces or Faces

Creates single points on an existing set of surfaces or faces at a specified u,v parametric location on the surface.


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Point Extract from Surfaces or Faces Method Example

Creates Point 5 using the Create/Extract Point from Surface or Face method, where the point is located at is equal to 0.333 and is equal to 0.666, on Surface 1. 1 u 2 v


Extracting Multiple Points from Surfaces or Faces

Creates multiple points on an existing set of surfaces or faces where the bounds of the grid of points is defined by a diagonal of two points.


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Multiple Point Extract from Surfaces or Faces Diagonal Method Example

Creates Points 7 through 28 on Surface 1 in the bounds defined by points 5 and 6.


Extracting Multiple Points from Surfaces or Faces

Creates multiple points on an existing set of surfaces or faces where the bounds of the grid of points is defined by a parametric , diagonal. 2


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Multiple Point Extract from Surfaces or Faces Parametric Method Example

Creates Points 5 through 28 on Surface 1 in the bounds defined by u-min=0.333, u-max=0.666, v-min=0.333, and v-max=0.666.


Parametric Bounds for Extracting Points from a Surface


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Interpolating Points

Between Two Points

The Interpolate method using the Point option will create n points of uniform or nonuniform spacing between a specified pair of point locations, where n is the number of interior points to be created. The point location pairs can be existing points, vertices, nodes or other point location provided by the Point select menu.


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Point Interpolate Method With Point Option Example

Creates five interior points starting with Point 3 that are between Points 1 and 2, using the Create/Interpolate/Point option. The spacing is nonuniform at L2/L1 = 2.0.


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Point Interpolate Method With Point Option Example

Same as the previous example, except the five new points are uniformly spaced between Nodes 1 and 2, by using the Point select menu icon listed below.


Interpolating Points on a Curve

The Interpolate method using the Curve option creates n points along an existing curve or edge of uniform or nonuniform spacing where n is the number of interior points to be created.


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• Topology

• Connectivity

• Display>Geometry (p. 385) in the Patran Reference Manual


Point Interpolate Method With Curve Option Example

Creates five uniformly spaced interior points, starting with Point 6 on Curve 1, using the Create/Point/Interpolate/Curve option.

Point Interpolate Method With Curve Option Example

Creates Points 5 through 9 that are nonuniformly spaced by using the Create/Interpolate/Curve option, where the points are created on an edge of Surface 1.


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Intersecting Two Entities to Create PointsThe Intersect method creates points at the intersection of any of the following pairs of entities: Curve/Curve, Curve/Surface, Curve/Plane, Vector/Curve, Vector/Surface, Vector/Plane. One point will be created at each intersection location. The pair of entities should intersect within a value defined by the Global Model Tolerance. If the entities do not intersect, Patran will create a point at the closest approach on each specified curve, edge, or vector for the Curve/Curve and Vector/Curve intersection options.


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• Topology

• Preferences Commands (p. 439) in the Patran Reference Manual

Point Intersect Method At An Edge Example

Creates Point 17, using the Create/Intersect method, at the intersection of Curve 3 and an edge of Surface 1.


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Point Intersect Method with Two Curves Example

Creates Points 1 and 2, using the Create/Intersect method, at the intersection of Curves 1 and 2.


Point Intersect Method with Two Curves Example

Creates Points 1 and 2, using the Create/Intersect method. Because the curves do not intersect, Points 1 and 2 are created at the closest approach of the two curves.


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Point Intersect Method with a Curve and a Surface Example

Creates Points 1, 2 and 3 using the Create/Intersect method at the intersection of Curve 6 with Surface 1.


Point Intersect Method with a Curve and a Plane Example

Creates Points 1, 2, and 3 using the Create/Intersect method at the intersection of Curve 2 with Plane 1.


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Point Intersect Method with a Vector and a Curve Example

Creates Points 1, 2, and 3 using the Create/Intersect method at the intersection of Vector 1 with Curve 2.


Point Intersect Method with a Vector and a Curve Example

Creates Point 1 on Vector 1 and Point 2 on Curve 2, using the Create/Intersect method. Since the entities do not intersect, Points 1 and 2 are created at the closest approach between the Vector and the Curve.


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Point Intersect Method with a Vector and a Surface Example

Creates Points 1 and 2 using the Create/Intersect method at the intersection of Vector 1 and Surface 1.


Point Intersect Method with a Vector and a Plane Example

Creates Point 1 using the Create/Intersect method at the intersection of Vector 2 and Plane 1.


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Creating Points by Offsetting a Specified DistanceThe Offset method creates a point on an existing curve by offsetting a specified model space distance from an existing point on the same curve.


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Point Offset Method Example

Creates point 3 on curve one, .75 units from point 1 using Create/Point/Offset.


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Piercing Curves Through Surfaces to Create PointsThe Pierce method creates points at the intersection between an existing curve or edge and a surface or solid face. The curve or edge must completely intersect with the surface or solid face. If the curve or edge intersects the surface or face more than one time, Patran will create a point at each intersection.


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Point Pierce Method Example

Creates Point 15, using the Create/Pierce method at the location where Curve 3 intersects Surface 1.


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Point Pierce Method Example

This example is the same as the previous example, except the curve is defined by Points 13 and 14 by using the Curve select menu icon listed below.


Projecting Points Onto Surfaces or FacesThe Project method creates points by projecting an existing set of points onto a surface or solid face through a defined Projection Vector. New points can be projected from other points, vertices, nodes or other point locations provided on the Point select menu.


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• Topology

• The Viewing Menu (Ch. 7) in the Patran Reference Manual

Point Project Method With Normal to Surf Option Example

Creates Points 21 through 28, using the Create/Project/Normal to Surf option. Points 13:16, 18:20 and Node 1 are all projected normally onto Surface 1. Notice Delete Original Points is pressed in.


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Point Project Method With Define Vector Option Example

Creates Points 21 through 28, using the Create/Point/Project/Define Vector option. The points are projected onto Surface 1 through the vector <-1 0 1> that is expressed within the Refer. Coordinate Frame, Coord 1. Notice that Delete Original Points is pressed in.


Point Project Method With View Vector Option Example

Creates Points 21 through 28, using the Create/Project/View Vector option. The points are projected onto Surface 1 using the view angle of the current viewport. Notice that Delete Original Points is pressed in and Points 13 through 20 are deleted.


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Creating Curves Between Points

Creating Curves Through 2 Points

The Point method using the 2 Point option creates straight parametric cubic curves between two existing point locations. The point locations can be existing points, vertices, nodes, or other point locations provided on the Point select menu.


Tip: More Help:


• Parametric Cubic Geometry

• PATRAN 2 Neutral File Support For Parametric Cubic Geometry

Curve Point Method With 2 Point Option Example

Creates Curve 3, using the Create/Point/2 Point option, which is between Point 1 and Node 10.


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The Point method using the 3 Point option creates parametric cubic curves that pass through three existing point locations where the starting point defines the curve at and the ending point defines

the curve at . The point locations can be existing points, vertices, nodes, or other point locations

provided on the Point select menu.

1 0=

1 1=


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Creates Curve 1, using the Create/Point/3 Point option, which is created through Points 1 and 2 and Node 10. Point 2 is located on the curve at x1(u) =0.5.


This example is the same as the previous example, except Point 2 is located on the curve at =0.75,

instead of 0.5.

1 u



The Point method using the 4 Point option creates parametric cubic curves that pass through four existing point locations where the starting point defines the curve at and the ending point defines the curve

at . The point locations can be existing points, vertices, nodes, or other point locations provided

on the Point select menu.

1 0=

1 1=


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Creates Curve 1, using the Create/Point/4 Point option, which is created through Points 1, 2 and 3 and Node 10. Point 2 is located at =0.333 and Point 3 is located at =0.667.1 u 1 u


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This example is the same as the previous example, except that Point 2 is located at x1(u) =0.25 and Point 3 is located at x1(u) =0.80.


Curve 4 Point Parametric Positions Subordinate Form

This subordinate form is displayed when the Parametric Positions button is pressed on the Geometry Application’s Create/Curve/Point form for the 4 Point option.


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Creating Arced Curves (Arc3Point Method)The Arc3Point method creates true arced curves that pass through three specified point locations. Patran calculates the arc’s center point location and the radius and angle of the arc. The three point locations can be points, vertices, nodes, or other point locations that are provided on the Point select menu.


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• Topology

• Matrix of Geometry Types Created

Curve Arc3Point Method Example

Creates Curve 3, using the Create/Arc3Point method, which creates a true arc through Points 1 through 3. Notice that Create Center Point is pressed which created Point 4.


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Curve Arc3Point Method Example

This example is similar to the previous example, except that the point locations for the arc are specified with point coordinate locations.


Creating Chained CurvesThe Chain method creates a chained composite curve from one or more existing curves or edges. The existing curves and edges must be connected end to end. If a chained curve is used to create planer or general trimmed surfaces for an inner loop, they must form a closed loop. Chained curves are used to create planar or general trimmed surfaces using the Create/Surface/Trimmed form.


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• Trimmed Surfaces

• Creating Trimmed Surfaces

• Disassembling a Chained Curve

Curve Chain Method Example

Creates Curve 11, using the Create/Chain method, which is created from Curves 3 through 10. Notice that Delete Constituent Curves is pressed and Curves 3 through 10 are deleted.


Creating Conic CurvesThe Conic method creates parametric cubic curves representing a conic section (that is, hyperbola, parabola, ellipse, or circular arc), by specifying point locations for the starting and ending points of the conic and the conic’s focal point. The point locations can be points, vertices, nodes or other point locations provided on the Point select menu.


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Curve Conic Method Example

Creates Curve 1, using the Create/Conic method whose focal point is Point 3, the starting and ending points are Points 1 and 2, and the conic altitude is 0.50.


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Curve Conic Method Example

This is the same as the previous example, except that the conic altitude is increased to 0.75 from 0.50 for Curve 2.


Extracting Curves From Surfaces

Extracting Curves from Surfaces Using the Parametric Option

The Extract method creates curves on an existing set of surfaces or solid faces by specifying the surface’s or face’s parametric or coordinate location where has a range of and has a range

of .

1 2 1 0 1 1 2

0 2 1


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Curve Extract Method With the Parametric Option Example


Creates Curve 1, using the Create/Extract/Parametric option. The curve is created on Surface 2 at

= 0.75. Notice that the parametric direction is displayed.


This example is the same as the previous example, except that Curve X is created at = 0.75, instead

of = 0.75.

2 v

1 u

2 v


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Creates Curve 3 which is at on a surface defined by Curve 2 and an edge of Surface 1 by

using the Surface select menu icons listed below.

2 v 0.25=


Extracting Curves From Surfaces Using the Edge Option

The Extract method creates curves on specified edges of existing surfaces or solid faces.


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Curve Extract Method With Edge Option Example

Creates Curve 3, using the Create/Extract/Edge option. The curve is created on one of the edges of Surface 1.


Creating Fillet CurvesThe fillet method is intended for use with 2D construction. The created curve is a circular arc. For this reason, the method will not work if the provided curves are not co-planar. The Patran 2.5 switch overrides this requirement and places no restriction on coplanarity. The result is a single cubic line so that it is more like a slope continuous blend between the 2 curves.


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Curve Fillet Method Example

Creates Curve 3, using the Create/Fillet method. The fillet curve is created between Curve 1 and Point 4 and Curve 2 and Point 5, with a radius of 0.5. Notice Trim Original Curves is pressed.


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Curve Fillet Method Example

Creates Curve 3, using the Create/Fillet method. The fillet curve is created between Curve 1 and Point 2 and Curve 2 and Point 3, with a radius of 0.25.


Fitting Curves Through a Set of PointsThe Fit method creates a parametric cubic curve by fitting it through a set of two or more point locations. Patran uses a parametric least squares numerical approximation for the fit. The point locations can be points, vertices, nodes, or other point locations provided on the Point select menu.


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Curve Fit Method Example

Creates three curves starting with Curve 1, using the Create/Fit method. The curve is created through Points 1 through 6.


Creating Curves at Intersections

Creating Curves at the Intersection of Two Surfaces

The Intersect method using the 2 Surface option creates curves at the intersection of two surfaces or solid faces. The two surfaces or faces must completely intersect each other.


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Curve Intersect Method With 2 Surface Option Example

Creates Curve 1 using the Create/Intersect method with the 2 Surface option. The curve is located at the intersection of Surfaces 1 and 2.



This example is similar to the previous example, except the second surface is instead defined by Curves 2 and 3 by using the Surface select menu icon and selecting Curves 2 and 3 to create Surface 2.


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Creates Curve 1 using the Create/Intersect/2 Surface option. The curve is located at the intersection of Surfaces 1 and 4.


Creating Curves at the Intersection of a Plane and a Surface

The Intersect method with the Plane-Surface option creates curves at the intersection of a defined plane and a surface or a solid face. The plane and the surface or face must completely intersect each other.


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Curve Intersect Method With Plane-Surface Option Example

Creates Curve 1 which is located at the intersection of Surface 1 and a plane whose normal is defined at {[0 2.5 0][0 3.5 0]}.


Curve Intersect Method With the Plane-Surface Option Example

Creates Curve 1 which is located at the intersection of Surface 2 and a plane whose normal is defined by the Z axis of Coord 1, Coord 1.3, by using the Axis select menu icon listed below.


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Intersect Parameters Subordinate Form

The Intersect Parameters subordinate form appears when the Intersect Parameters button is pressed on the Create/Curve/Intersect application form.


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Creating Curves at the Intersection of Two Planes

This form is used to create a curve from the intersection of two planes.


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Creating Curve Intersect from Two Planes Example

Create curve 1 with a length of 0.334 from the intersection of plane 1 and 2.


Manifold Curves Onto a Surface

Manifold Curves onto a Surface with the 2 Point Option

The Manifold method with the 2 Point option creates curves directly on an existing set of surfaces or solid faces by using two point locations on the surface. The point locations must lie on the surface or face. The point locations can be points, vertices, nodes or other point locations provided on the Point select menu.


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Curve Manifold Method With the 2 Point Option Example

Creates three curves starting with Curve 1 using the Create/Manifold/2 Point option. The curves are created on Surface 1 between Point 7 and Points 2,5 and 8.

Curve Manifold Method With the 2 Point Option On a Face Example

Creates Curve 1 using the Manifold/2 Point option on a face of Solid 1 that is between Points 5 and 12.


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Manifold Curves onto a Surface With the N-Points Option

The Manifold/N-Points option creates curves directly on a set of surfaces or solid faces by using two or more point locations on the surface. The point locations must lie on the surface or face and they can be existing points, vertices, nodes or other point locations provided on the Point select menu.


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Curve Manifold Method With N-Points Option Example

Creates Curve 1 using the Create/Manifold/N-Points option. The curve is created on Surface 1 through Points 5, 8, 17, 18 and 4.


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Curve Manifold Method With N-Points Option On a Face Example

Creates Curve 1 using the Create/Manifold/N-Points option. The curve is created on the top face of Solid 1, through Points 6, 12, 13 and 5.


Manifold Parameters Subordinate Form

The Manifold Parameters subordinate form appears when the PATRAN 2 Convention toggle is ON and the Manifold Parameters button is pressed on the Create/Curve/Manifold application form.


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Creating Curves Normally Between a Point and a Curve (Normal Method)The Normal method creates straight parametric cubic curves from a point location, normally to a curve or an edge. The point location can be points, vertices, nodes, or other point locations provided on the Point select menu.


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Curve Normal Method Example

Creates Curve 6 using the Create/Normal method. The curve is created from Point 13 normally to the edge of Curve 5.


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Curve Normal Method From An Edge Example

Creates Curve 1 using the Create/Normal method. The curve is created from Point 20 normally to an edge of Surface 4 by using the Curve select menu icon listed below.


Creating Offset Curves

Creating Constant Offset Curve

This form is used to create a constant offset curve.


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Creating Constant Offset Curve Example

Create offset curves 2 thru 4 by offsetting a distance of .5 from curve 1 using a repeat count of 3.


Creating Variable Offset Curve

This form is used to create a variable offset curve.


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Parameterization Control for Variable Offset Curve

This form is used to define the parameterization control for the offset curve. There are two types; Arc Length and Parameter Value.


Creating Variable Offset Curve Example

Create curves 2 thru 3 from curve 1 by offsetting a start distance of .25 and an end distance of 1. Use parameter values of .5 and 1.0.


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Projecting Curves Onto SurfacesThe Project method creates curves by projecting a set of curves or edges along a defined projection vector, onto a surface or solid face.


Available options are:

Normal to Plane - The curves or edges in Curve List will be projected through a vector that is normal to at least one of the curves or edges that define a plane.

Normal to Surf - The curves or edges in Curve List will be projected through a vector that is normal to the surface or solid face specified in Surface List.

Define Vector - The project direction is defined by the vector coordinates entered in the Projection Vector databox which is expressed within the Refer. Coordinate Frame. Example: <1 1 0>. The Vector Select menu will appear to allow you alternate ways to cursor define the vector definition.

View Factor - The project direction is defined by the view angle in the current viewport. Patran will project the existing points using the normal direction of the screen.


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• Topology


• The Viewing Menu (Ch. 7) in the Patran Reference Manual

Curve Project Method With the Normal to Plane Option Example

Creates Curve 7 using the Create Project/Normal to Plane option. The curve is projected from Curve 6 onto Surface 2 that is normal to the plane defined by Curve 6.


Curve Project Method With the Normal to Surf Option Example

Creates Curve 8 using the Create/Project/Normal to Surf option. The curve is projected from Curve 6 normally onto Surface 2. Notice that Delete Original Curves is pressed and Curve 6 is deleted.


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Curve Project Method With Define Vector Option Example

Creates Curve 7 with the Define Vector option. The curve is projected from Curve 6 onto Surface 2 through the vector that is defined by Points 19 and 20 by using the Vector select menu icon listed below.


Curve Project Method With View Vector Option Example

Creates Curve 7 with the View Vector option. The curve is projected from Curve 6 onto Surface 2 through the view angle of the current viewport. Notice that Delete Original Curves is pressed and Curve 6 is deleted.


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Project Parameters Subordinate Form

The Project Parameters subordinate form appears when the Project Parameters button is pressed on the Create/Curve/Project application form.


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Creating Piecewise Linear CurvesThe PWL method will create a set of piecewise linear (or straight) parametric cubic curves between a set of existing point locations. The point locations can be points, vertices, nodes or other point locations provided on the Point select menu.


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Curve PWL Method Example

Creates seven curves starting with Curve 5 using the Create/PWL method. The straight curves are created through Points 12 through 18 and Node 1.


Creating Spline Curves

Creating Spline Curves with the Loft Spline Option

The Spline method using the Loft Spline option creates piecewise cubic polynomial spline curves that pass through at least three point locations. Patran processes the slope continually between the point segments. The point locations can be points, vertices, nodes or other point locations provided on the Point select menu.


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Curve Spline Method With Loft Spline Option Example

Creates Curve 1 using the Create/Spline method with the Loft Spline option. The curve is created through Points 1 through 5. Notice that since End Point Slope Control are not pressed in, Start and End Point Tangent Vector are disabled.


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Curve Spline Method With Loft Spline Option Example

This example is the same as the previous example, except that Curve 2 is created with End Point Slope Control is pressed in. The Start Point Tangent Vector is defined by Points 1 and 2, and the End Point Tangent Vector is defined by Points 4 and 5, using the Vector select menu icon listed below.


Creating Spline Curves with the B-Spline Option

The Spline/B-Spline option creates spline curves that pass through at least three point locations. Patran processes the slope continually between the point segments. The point locations can be points, vertices, nodes or other point locations provided on the Point select menu.


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Curve Spline Method With B-Spline Option Example

Creates Curve 1 with the B-Spline option. The B-spline has an order of 3 and uses Points 1 through 5. Since Interpolation is not pressed, the curve is not forced to pass through all the points.


This example is the same as the previous example, except that the order for Curve 2 is three, instead of five.


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This example is the same as the previous example, except Interpolation is pressed and Curve 3 is forced to pass through Points 1 through 5.


Creating Curves Tangent Between Two Curves (TanCurve Method)The TanCurve method creates straight parametric cubic curves that are tangent between two existing curves or edges. The curves or edges cannot be straight, or else Patran will not be able to find the tangent location on each curve.


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Curve TanCurve Method Example

Creates Curve 10 using the Create/TanCurve method. The curve is tangent between Curves 9 and 8 with Points 26 and 25 as the endpoints selected in the Point 1 and 2 Lists. Notice that Trim Original Curves is pressed.


Creating Curves Tangent Between Curves and Points (TanPoint Method)The TanPoint method creates straight parametric cubic curves that are tangent between a point location and a curve or an edge. The curve or edge cannot be straight, or else Patran will not be able to find the tangent location. The point locations can be points, vertices, nodes or other point locations provided on the Point select menu.


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Curve TanPoint Method Example

Creates Curve 10 using the Create/TanPoint method. The curve is tangent between Point 25 and Curve 9. Notice that Trim Original Curves is pressed in and Curve 9 is trimmed.


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Curve TanPoint Method Example

Creates Curve 1 using the Create/TanPoint method. The curve is tangent between Point 9 and an edge of Surface 1.


Creating Curves, Surfaces and Solids Through a Vector Length (XYZ Method)The XYZ method creates parametric cubic curves, surface, or solids from a specified vector length and origin. The origin can be expressed by cartesian coordinates or by an existing vertex, node or other point location provided by the Point select menu.


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Curve XYZ Method Example

Creates Curve 3 using the Create/XYZ method, whose origin is located at Point 6 and whose vector orientation and length is <20 10 0>.


Surface XYZ Method Example

Creates Surface 3 using the Create/XYZ method, whose origin is located at Point 6 and whose vector orientation and length is <20 10 5>.


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Solid XYZ Method Example

Creates Solid 1 whose origin is located at Point 6 and whose vector orientation and length is <20 10 5> which is expressed within the Reference Coordinate Frame, Coord 0.


Creating Involute Curves

Creating Involute Curves with the Angles Option

The Involute/Angles option creates parametric cubic curves from a point location. The point location can be a point, vertex, node or other point locations provided on the Point select menu. Involute curves are like the unwinding of an imaginary string from a circular bobbin. Intended for gear designers, the Angles option requires the angle of the unwinding and the starting angle.


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Curve Involute Method With the Angles Option Example

Creates four curves starting with Curve 5 using the Create/Involute/Angles option, where the curve is unwound 360 degrees about the involute axis {[0 0 0][0 0 1]}, from Point 13.


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Creating Involute Curves with the Radii Option

The Involute/Radii option creates parametric cubic curves from a point location. The point location can be a point, vertex, node or other point location provided on the Point select menu. Involute curves are like the unwinding of an imaginary string from a circular bobbin. Intended for the material modeling community, the Radii option requires the base radius of the bobbin and the radius of the stop of the curve.


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Curve Involute Method With the Radii Option Example

Creates six curves starting with Curve 5 using the Create/Involute/Radii option, where the curve is unwound starting with a base radius of 0.1 and a stop radius of 2, about the involute axis {[0 0 0][0 0 1]}, starting from Point 13.


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Revolving Curves, Surfaces and SolidsThe Revolve method creates curves, surfaces or solids by the rotation of a point, curve or surface location, respectively. The new geometric entity is rotated about a defined axis. Point locations can be points, vertices, or nodes, Curve locations can be curves or edges. Surface locations can be surfaces or solid faces.


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Curve Revolve Method Example

Creates Curves 5 and 6 using the Create/Revolve method, where the curves are created from Points 12 and 13 about the axis, {[0 0 0][0 0 1]} for 180 degrees, with an offset of 30 degrees.


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Surface Revolve Method Example

Creates Surface 1 where the surface is created from a curve defined by Points 1 and 2 using the Curve select menu icon listed below. The surface is revolved 45 degrees about the axis {Point 1 [x1 y1 1]}.


Surface Revolve Method Example

Creates four surfaces starting with Surface 2 using the Create/Revolve method, where the surfaces are created from Curves 9 through 12 about the axis, {[0 0 0 ] [ 1 0 0 ]} for 360 degrees.


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Solid Revolve Method

Creates Solid 1 using the Create/Revolve method, where the solid is created from Surface 2. The axis is defined by the Points 15 and 12 using the Axis select menu icon listed below, for a rotation of 90 degrees.


Solid Revolve Method

Creates Solid 1 using the Create/Revolve method, where the solid is created from Surface 1 about the X axis of Coord 1 (by using the Axis select menu listed below) for 90 degrees.


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Creating Orthogonal Curves (2D Normal Method)

Creating Orthogonal Curves with the Input Length Option

The 2D Normal/Input Length option creates straight parametric cubic curves that lie on a defined 2D plane and is perpendicular to a curve or an edge. The curve is defined from a specified point location. The point location can be a point, vertex, node or other point locations provided on the Point select menu.


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Curve 2D Normal Method With the Input Length Option

Creates Curve 1 with the Input Length option, where the curve is 1 unit long; it lies within the plane whose normal is the Z axis of Coord 3; it is perpendicular to the top edge of Surface 1; and its starting point is near Point 3.


Curve 2D Normal Method With the Input Length Option

This example is the same as the previous example, except that Flip Curve Direction is pressed.


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Creating Orthogonal Curves with the Calculate Length Option

The 2D Normal/Calculate Length option, creates straight parametric cubic curves that lie on a defined 2D plane and is perpendicular to an existing curve or edge. The curve is defined from specified point location. The point location can be a point, vertex, node or other point locations provided on the Point select menu.


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Curve 2D Normal Method With the Input Length Option Example

Creates Curve 1 with the Input Length option. The distance of Curve 1 is 1.0; it lies within the plane whose normal is the global coordinate frame’s X axis, Coord 0.1; and it is starts from a point that is closest to Point 6.


Curve 2D Normal Method With the Calculate Length Option Example

Creates Curve 1 with the Calculate Length option. The distance of Curve 1 is the distance between Points 3 and 4; it lies within the plane whose normal is the Z axis of Coord 3; and it starts from a point that is closest to Point 3.


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Creating 2D Circle CurvesThe 2D Circle method creates circular curves of a specified radius that is within a defined 2D plane, based on a center point location. The point location can be a point, vertex, node or other point locations provided on the Point select menu.


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Curve 2D Circle Method With the Input Radius Option Example

Creates Curve 5 using the Create/2D Circle method with the Input Radius option, where the circle has a radius of 1.0, its center point is at Node 1, and it lies within the plane whose normal is the Z axis of Coord 0.


Curve 2D Circle Method With the Calculate Radius Option Example

Creates Curve 5 using the Create/2D Circle/Calculate Radius option, where the radius is measured from Point 12 to Node 1, its center point is at Node 1, and it lies within the plane whose normal is the Z axis of the global rectangular coordinate frame, Coord 0.


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Creating 2D ArcAngle CurvesThe 2D ArcAngles method creates arced curves within a defined 2D plane. The Arc parameter inputs are Radius, Start Angle and End Angle. The point location for the arc’s center is to be input.


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Curve 2D ArcAngle Method Example

Creates Curve 1 using Create/Curve/2D ArcAngles.


Creating Arced Curves in a Plane (2D Arc2Point Method)

Creating Arced Curves with the Center Option

The 2D Arc2Point method creates arced curves within a defined 2D plane. Two options are provided. The Center option inputs are point locations for the arc’s center and the arc’s starting and ending points. The Radius option inputs are the radius and point locations for the arc’s starting and ending points.


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Curve 2D Arc2Point Method With Center Min. Angle Option Example

Creates Curve 5 using the Create/2D Arc2Point method, where the Minimum Angle is chosen; the arced curve is between Point 13 and Node 1; its center point is Point 12; and the curve lies within the plane whose normal is {[0 0 0][0 0 1]}.


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Curve 2D Arc2Point Method With Center Max. Angle Option Example

Creates Curve 5 using the Create/2D Arc2Point method, where the Maximum Angle is chosen; the arced curve is between Point 13 and Node 1; its center point is Point 12; and the curve lies within the plane whose normal is {[0 0 0][0 0 1]}.


Creating Arced Curves with the Radius Option

The 2D Arc2Point method creates arced curves within a defined 2D plane. Two options are provided. The Center option inputs are point locations for the arc’s center and the arc’s starting and ending points. The Radius option inputs are the radius and point locations for the arc’s starting and ending points.


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Curve 2D Arc2Point Method with Radius Option Example

Creates Curve 1 by creating an arc with a radius of 1.5 using [-1 -.5 -1] and [1 1 1] as start/end points and in the Z construction plane.


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Arc2Point Parameters Subordinate Form

The Arc2Point Parameters subordinate form appears when the Arc2Point Parameters button is pressed on the Create/Curve 2D Arc2Point application form.


Creating Arced Curves in a Plane (2D Arc3Point Method)The 2D Arc3Point method creates arced curves within a defined 2D plane, based on point locations for the arc’s starting, middle and ending points. The point locations can be points, vertices, nodes or other point locations provided on the Point select menu.


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Curve 2D Arc3Point Method Example

Creates Curve 5 using the Create/2D Arc3Point method. The arced curve is created through the Points 13, 14 and Node 1 and it lies within the plane whose normal is {[0 0 0][0 0 1]}. Notice that Create Center Point is pressed in and Point 16 is created.


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Creating Surfaces from Curves

Creating Surfaces Between 2 Curves

The Curve method using the 2 Curve option creates surfaces between two curves or edges. Degenerate three-sided surfaces can be created. See Building a Degenerate Surface (Triangle) for more information.


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Surface Curve Method With the 2 Curve Option Example

Creates Surface 2 using the Create/Curve/2 Curve option. The curve is created between Curves 5 and 6.


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Surface Curve Method With the 2 Curve Option Example

Creates Surface 2 that is degenerate with the 2 Curve option which is between an edge of Surface 1 and a zero length curve defined by Point 5, twice.


Creating Surfaces Through 3 Curves (Curve Method)

The Curve method using the 3 Curve option creates surfaces that pass through three existing curves or edges.


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Surface Curve Method With 3 Curve Option Example

Creates Surface 2 using the Create/Curve/Curve option. The curve is created through Curves 5, 6 and 8.



Creates Surface 2 through Curves 2, 3 and an edge of Surface 1.


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Creating Surfaces Through 4 Curves (Curve Method)

The Curve method using the 4 Curve option creates surfaces that pass through four existing curves or edges.


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Creates Surface 3 using the Create/Curve/4 Curve option. The curve is created through Curves 5,6 and 8 and the edge of Surface 2 by using the Curve select menu icon listed below.


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Creating Surfaces from N Curves (Curve Method)

The Curve method using the N-Curves option creates surfaces that pass through any number of curves or edges.


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Surface Curve Method With N-Curves Option Example

Creates Surface 2 using the Create/Curve/N-Curves option. The curve is created through Curves 5,6,8,9 and 10.


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Creating Composite Surfaces


Figure 4-1 The Composite method creates surfaces composed from multiple surfaces.

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General Comments

If valid boundary loops are identified and any of the vertices in the vertex list are not part of a boundary, the location will be marked red and the user will be prompted to “ignore and continue” or “stop”.

The Surface Builder always computes the optimal view plane based on the Surface List. In most cases this is satisfactory; however, in some instances, it can create a very distorted parametrization of the new surface, leading to poor finite element mesh quality. Sometimes the view selected by the user as “best” is more successful than the recommended optimal plane (i.e., answer “No” to the prompt asking permission to reorient the model to a better view); otherwise, the proposed Composite Surface will have to be represented by multiple composite surfaces.

If the Composite Surface Builder often fails because of unresolved boundary edges, the gap and clean-up tolerances are most likely too small. If edges disappear the tolerances are probably too large. The default gap and clean-up tolerances are set equal to the global model tolerance and can be changed on the Options form.


Composite Surface Options

Surface Composite Method Example

Creates Surface 2 from the surfaces in the viewport.


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Decomposing Trimmed SurfacesThe Decompose method creates four sided surfaces from an existing surface or solid face by choosing four vertex locations. This method is usually used to create surfaces from a multi-sided trimmed surface so that you can either mesh with IsoMesh or continue to build a tri-parametric solid.

See Decomposing Trimmed Surfaces for more information on how to use the Decompose method.


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Surface Decompose Method Example

Creates Surfaces 3, 4 and 5 using the Create/Decompose method. The surfaces are created from Trimmed Surface 2 and they are defined by the cursor selected vertices listed in the Surface Vertex databoxes on the form.


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Creating Surfaces from Edges (Edge Method)The Edge method creates three or four sided surfaces that are bounded by three or four intersecting curves or edges, without manifolding the surface to an existing surface or face.


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• Surface Edge Method With the 3 Edge Option Example

Creates Surface 3 using the Create/Edge/3 Edge option. The degenerate surface is created from Curves 5 and 6 and the edge of Surface 2. See Building a Degenerate Surface (Triangle).


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Surface Edge Method With the 4 Edge Option Example

Creates Surface2 using the Create/Edge/4 Edge option. The surface is created from Curves 5 through 8.


Extracting Surfaces

Extracting Surfaces with the Parametric Option

The Extract method creates surfaces by creating them from within or on a solid, at a constant parametric , , or coordinate location, where has a range of , has a range of ,

and has a range of . One surface is extracted from each solid.

1 u 2 v 3 w 1 0 1 1 2 0 2 1

3 0 3 1


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Surface Extract Method With the Parametric Option Example

Creates Surface 2 using the Create/Extract/Parametric option. The surface is created at

within Solid 1. Notice the parametric direction is displayed near Point 19.

3 w 0.75=


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Surface Extract Method With the Parametric Option Example

Creates Surface 3 using the Create/Extract/Parametric option. The surface is created at

within a solid that is defined by Surfaces 1 and 2 by using the Solid select menu icons listed below.

3 w 0.75=


Extracting Surfaces with the Face Option

The Extract method creates surfaces by creating them on a specified solid face. One surface is extracted from each solid face.


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Surface Extract Method With the Face Option Example

Creates Surfaces 2 and 3 using the Create/Extract/Face option. The surface is created on two faces of Solid 10.


Creating Fillet SurfacesThe Fillet method creates a parametric bi-cubic surface between two existing surfaces or solid faces. The existing surfaces or faces do not need to intersect. If they do intersect, the edges of the surfaces or faces must be aligned, and they must intersect so that a nondegenerate fillet can be created.


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Surface Fillet Method Example

Creates Surface 4 using the Create/Fillet method that is between Surfaces 1 and 3 with the fillet’s endpoints, Points 2 and 10, cursor selected. Surface 4 has a varying fillet radius of 0.25 to 0.5.


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Surface Fillet Method Example

Creates Surface 5 using the Create/Fillet method that is between Surfaces 3 and 4 with the fillet’s endpoints, Points 19 and 25, cursor selected. Surface 5 has a constant fillet radius of 0.75.


Matching Adjacent SurfacesThe Match method creates parametric bi-cubic surfaces with common boundaries (or matched edges) from a pair of topologically incongruent surfaces or solid faces that have two consecutive common vertices but unmatched edges. The surface pair need not have matching parametric orientations. Patran requires geometry to be topologically congruent for IsoMesh and Paver to create coincident nodes at the common boundaries. See Topological Congruency and Meshing for more information.

You can also match incongruent surfaces with the Edit action’s Edge Match method. See Matching Surface Edges for more information.


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• Meshing Surfaces with IsoMesh or Paver (p. 13) in the Reference Manual - Part III

Surface Match Method Example

Creates Surface 4 using the Create/Match method that is topologically congruent with Surface 2. Notice that Delete Original Surfaces is pressed in and Surface 3 is deleted.


Creating Constant Offset SurfaceThis form is used to create a constant offset surface.


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Creating Constant Offset Surface Example

Create surfaces 2 and 3 by offsetting from surface 1, a distance of 0.5 with a repeat count of 2 and reversing the direction vector of surface 1.


Creating Ruled SurfacesThe Ruled method creates ruled surfaces between a pair of curves or edges.


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Surface Ruled Method Example

Creates Surface 1 using the Create/Ruled method which is created between Curves 1 and 2.


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Surface Ruled Method Example

Creates Surface 3 using the Create/Ruled method which is created between Curve 5 and an edge of

Surface 2 by using the Curve select menu icon listed below. Notice that since Equal Parametric Values

was pressed in, Surface 3’s parametric direction is the same as for Curve 5.1


Creating Trimmed SurfacesThe Trimmed method creates a trimmed surface. You must first create at least one chained curve for the surface’s outer loop or boundary by using the Create/ Curve/Chain form before using this form, or by bringing up the Auto Chain form from within this form. (Note that an outer loop must be specified, and the inner loop being specified is not necessary.) Trimmed surfaces can be meshed by Paver.


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• Creating Chained Curves


Creating Trimmed Surfaces with the Surface Option

Creates Surface 3 using the Create/Surface/Trimmed/Surface option which is created from chained Curve 22 for the outer loop, chained Curve 21 for the inner loop and Surface 2 for the parent surface. Notice that Delete Outer and Inner Loop and Delete Constituent Surface are pressed in and Curves 21 and 22 and Surface 2 are deleted.


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Creating Trimmed Surfaces with the Planar Option

Creates Surface 2 using the Create/Surface/Trimmed/Planar option which is created from chained Curve 14 for the outer loop and chained Curve 13 for the inner loop. Notice that Delete Outer Loop and Delete Inner Loop are pressed in and Curves 13 and 14 are deleted.


Auto Chain Subordinate Form

The Auto Chain form provides a more interactive, user-controllable way of creating Chain Curves. A start curve is selected for the chain and then during the creation of the chain, if necessary, the user will be prompted to make decisions on how to proceed by selecting the appropriate buttons. Toggles are provided for additional control of the chain curve creation. This subordinate form is accessible from either the Create/Curve/Chain or the Create/Surface/Trimmed forms.


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Creating Trimmed Surfaces with the Composite Option

The Create/Surface/Trimmed/Composite option provides a tool for combining surfaces into a single trimmed surface, where the parent trimmed surfaces may have gaps or overlaps of a specified distance, and are not required to be topologically congruent. Though the constituent surfaces are used for all evaluations without any approximation, the resulting composite surface is seen as a single trimmed surface by all operations that reference it, such as the Paver.

Shadow Surface Method

The method used to create a composite trimmed surface is called a Shadow Surface Method. The best way to describe a shadow surface is to use a real life analogy. Consider a cloud in the sky to be a shadow surface. Then the sun, being the light source behind the cloud, creates a shadow on the planet Earth, only

Next: Used to update the "Choose Curve to Continue" databox when multiple choices are possible, i.e. a branch.

OK: Used to finalize the selection on the curve echoed in the "Choose Curve to Continue" databox and continue the auto chain process.

Previous: Used to update "Choose Curve to Continue" databox when more than two curves form a branch. Use in conjunction with the Next button.

Quit: Used to end the auto chain process without attempting to creating a chain.

Backup: Used to backup one curve at a time in the list of curves that have been previously selected as constituents for the resulting chain.

Stop: Used to end the auto chain process and attempt to create a chain from the constituent curves. (Only necessary when pressing the Apply button did not create a chain.)

Delete: Used to delete the curve in the "Choose Curve to Continue" databox from the database.

Break: Used to break the curve in the "Choose Curve to Continue" databox.


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in the area blocked by the cloud. The same is true of the shadow surface, except a view vector is used to determine the light direction. The shadow itself is called an Under Surface, whose valid region is defined by where the outlines of the shadow surface appear with respect to a given view.

The Shadow Surface itself is a collection of specified surfaces, which may have gaps or overlaps of a specified distance, and may or may not be topologically congruent. It is bounded by outer and inner loops, defined as closed chains of curves or surface edges.

During surface evaluations, the Under Surface is used to classify the point relative to which constituent surface (amongst the Shadow Surface) contains it. The point is mapped to the parameter space of that constituent surface, and the evaluation is done directly on that surface.

Creating Composite Surfaces

The steps in creating composite surfaces are, for the most part, the same as those for creating a normal trimmed surface, with the following exceptions:

• More than one surface is specified to define the curvature (multiple parent surfaces).

• A Gap Distance parameter must be specified to define the maximum length for gaps or overlaps.

• An appropriate view must be obtained, satisfying the following:

• Double Intersections between the Shadow Surface and the view vector must not occur. In other words, the Shadow Surface must not wrap around on itself relative to the current view. This is because the Under Surface is flat, and there is not necessarily a one-to-one mapping from the Shadow Surface to the Under Surface. Surfaces that combine to create a cylinder, therefore, cannot be used to create a single composite surface.

• No Dead Space. Unpredictable results will occur if any portion of the Shadow Surface does not have an Under Surface counterpart. An example of dead space would be an area on the Shadow Surface which runs parallel to the view vector. Since this portion has no area with respect to its projection onto the Under Surface, it will not be represented properly in the resulting composite surface. This can cause unwanted holes or spikes in the geometry.


Surface Trimmed Method - Composite Option Example

Creates Surface 5 using the Create/Surface/Trimmed/Composite option which is created from chained Curve 5 for the outer loop, chained Curve 4 for the inner loop and Surface 1:4 for the parent surface. Notice that Delete Outer and Inner Loop and Delete Constituent Surface are pressed in and Curves 1 and 2 and Surfaces 1:4 are deleted.


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Creating Surfaces From Vertices (Vertex Method)The Vertex method creates four sided surfaces from four existing point locations that define the surface’s vertices or corners. The point locations can be points, vertices, nodes or other point locations provided on the Point select menu.


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Surface Vertex Method Example

Creates Surface 2 using the Create/Vertex method which is created from Points 12, 13, 14 and Node 1. Notice that since Manifold is not on, the Manifold Surface databox is disabled.


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Extruding Surfaces and SolidsThe Extrude method creates surfaces or solids by moving a curve or edge, or a surface or solid face, respectively, through space along a defined axis with the option of scaling and rotating simultaneously. This method is convenient for adding depth to a cross section, or for more complex constructions that require the full capabilities of this form.


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Surface Extrude Method Example

Creates Surface 2 using the Create/Extrude method which is created from Curve 5. The surface is extruded +10 units in the global Y direction.


Surface Extrude Method Example

This example is the same as the previous example, except that Surface 1 is extruded +10 units in the global Y direction about an angle of 90 degrees and with a scale factor of 2. The origin of the scale and rotation is at Point 14.


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Solid Extrude Method Example

Creates Solid 2 using the Create/Extrude method which is created from a face of Solid 1. The solid is extruded +10 units in the global Y direction, with a scale factor of 2. The origin of the scale is at Point 21.


Gliding Surfaces

Gliding Surfaces with the 1 Director Curve Option

The Glide method creates biparametric surfaces by sweeping base curve along a path defined by a set of director curves or edges.


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Surface Glide Method - 1 Director Curve Example

Creates Surfaces 2 through 4 using the Create/Glide method which is created from Curve 10 for the Director Curve and Curves 11, 13 and 14 for the Base Curves. The scale is set to 1.0 and Fixed Glide is pressed in.


Gliding Surfaces with the 2 Director Curve Option

This option sweeps a base curve along a path defined by a pair of director curves. Automatic scaling is optional.


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Surface Glide Method - 2 Director Curve Example

Creates Surface 1 by using Curves 1 and 2 as the director curves and Curve 3 as the base curve to glide along.


Creating Surfaces and Solids Using the Normal MethodThe Normal method creates parametric bi-cubic surfaces or solids which are defined by a set of base curves or surfaces, respectively, and an offset distance from those curves or surfaces in the direction of the curvature. The offset may be constant or have a varying thickness.


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Surface Normal Method Example

Creates Surface 2 using the Create/Normal method which is created from Curve 5. It has a varying thickness of 0.75 at and x2=0 and a thickness of 2.0 at x1=0 and x2=1. Notice that the parametric

direction is on.

1 0=


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Surface Normal Method Example

Creates Surface 2 which is created from an edge of Surface 1. It has a constant thickness of 0.25 and the normal direction is defined by a construction point, Point 9. Notice that the normal direction is measured from the first vertex of the edge (Point 5) to Point 9.


Solid Normal Method Example

Creates Solid 1 using the Create/Normal method which is created from Surface 1 and has a thickness of 0.5. Notice that since PATRAN 2 Convention is not pressed in, the Solids per Surface databox is disabled.


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This example is similar to the previous example, except that the thickness is -0.5 instead of +0.5.


Solid Normal Method From a Face Example

Creates Solid 2 using the Create/Normal method which is created from a face of Solid 1 and has a thickness of 0.25.


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Creating Surfaces from a Surface Mesh (Mesh Method)The Mesh method creates a surface from a congruent 2-D mesh. Vertices can be defined on the surface boundary by selecting nodes in the Outer Corner Nodes or Additional Vertex Nodes listboxes.

Every edge of the surface will have at least one node. If no node is selected to identify a vertex, then one will be selected automatically. The nodes entered in the Outer Corner Node listbox will define the parametrization of the surface and will also be a vertex. If no nodes are selected, 4 appropriate nodes will be selected automatically. Also the 4 nodes selected should be on the outer loop. Additional vertices can be defined by selecting nodes in the Additional Vertex Nodes listbox.

The longest free edge loop will be the outer loop of the surface. The holes inside the mesh can be preserved or closed by invoking the options in the Inner Loop Options pull-down menu. When few of the inner holes need to be preserved Inner Loop Options is set to Select. Identify the holes by selecting at


least 1 node on the hole. If selected, nodes on the outer loop and those not on the free boundary, will be ignored.

The parametrization of the surface can also be improved by setting Surface Creation Methods to Better Parametrization. However, if speed were important and the mesh used to create the surface is of poor quality, selecting the Fast option under the Surface Creation Methods pull-down menu would create a better surface.

Tessellated Surface is a representation of the underlying mesh that is used to create it. Therefore the surface is piecewise planar and the normals are not continuous. The surface is primarily generated to facilitate the meshing operation on complex surface models. Though these surfaces support most of the geometry operations, it has limitations due to the nature of the surface.

To create a tessellated surface the mesh should have the following characteristics:

• Congruent 2-D elements

• Should be one connected set of elements

• No more than 2 elements should share the same 2 nodes

• The outer or inner loop should not intersect.


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Created Tessellated Surface from Geometry Form

Figure 4-2

Creating Midsurfaces

Creating Midsurfaces with the Automatic Option

This form is used to create a Midsurface using the Automatic Method.

Note: When the Inner Loop Options is set to Select, a node listbox opens. Here the holes to be preserved can be identified by the nodes on its edge. Any nodes not on the hole edge or on the outer boundary will be ignored.


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Create Midsurface Automatic Example

Create surfaces 1t6 by automatically computing the midsurfaces of solid 1 where the solid wall thickness is less than 8.1.


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Creating Midsurfaces with the Manual Option

This form is used to create a Midsurface using the Manual Method. The resulting midsurface will be trimmed to the domain of the parent surface pairs.


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Create Midsurface Manual Example

Create surfaces 1t3 by manually selecting solid faces Solid 1.5 and Solid 1.9, Solid 1.4 and Solid 1.8, Solid 1.7 and Solid 1.10 as face pairs to create the midsurfaces from.


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311Chapter 4: Create ActionsCreating Solid Primitives

Creating Solid Primitives

Creating a Solid BlockThis form is used to create a solid block with user input a point, length, width, height, and reference coordinate frame. It also provides an option to perform boolean operation with the input target solid using the created block as the tool solid.

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Geometry Modeling - Reference Manual Part 2Creating Solid Primitives

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Creates solid blocks 1 and 2 at [0 0 0] and [2 0 0] with parameters of X=1.0, Y=1.0, Z=1.0 and X=2.0, Y=2.0, Z=2.0 respectively.

Creates solid block 1 at [-1 .5 .5] with parameters of X=5.0, Y=1.0, Z=1.0 while performing a boolean add operation with solid 1.


Creating Solid Cylinder

This form is used to create a solid cylinder with user input a point, height, radius, optional thickness, and optional reference coordinate frame. It also provides an option to perform boolean operation with the input target solid using the created cylinder as the tool solid.


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Creates solid cylinder 1 at point 1with parameters of Height=3.0, Radius=0.25, along X axis.


Creates Solid Cylinder 1 at point 1 with parameters Height=3.0, Radius=0.25, a wall thickness = 0.125 along X axis while performing a boolean add operation with solid 1.


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Creating Solid Sphere

This form is used to create a solid sphere with user input a point, radius, and optional reference coordinate frame. It also provides an option to perform boolean operation with the input target solid using the created sphere as the tool solid.


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Creates Solid Sphere 1 at [0 0 0] with a Radius of 1.0 along the Z axis.


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Creates Solid Sphere 1 at point 1with a Radius of 0.5 along the Y axis while performing a boolean add operation with solid 1.


Creating Solid Cone

This form is used to create a solid cone with user input a point, base radius, top radius, height, optional thickness, and optional reference coordinate frame. It also provides an option to perform boolean operation with the input target solid using the created cone as the tool solid.


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Creates Solid Cone 1 at [0 0 0] and Cone 2 at [3 0 0] along the Z axis with parameters Height=2.0, Base Radius=1.0, Top Radius=0.5 and Thickness for Cone 1=0.0 and Thickness for Cone 2=0.125


Creates Solid Cones 1 and 2 at [.5 1 .5] along the Y axis with parameters Height=-5.0, Base Radius=0.25, Top Radius=0.0625 while performing a boolean add operation with Solid 1 and 2.


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Creating Solid Torus

This form is used to create a solid torus with user input a point, major radius, minor radius, and optional reference coordinate frame. It also provides an option to perform boolean operation with the input target solid using the created torus as the tool solid.


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Creates Solid Torus 1 and 2 at [0 0 0] with parameters Major Radius=1.0, Minor Radius=0.5 and Torus 1 along the X axis and Torus 2 along the Y axis.


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Creates Solid Torus 1 at [0 0 0] along the Z axis with parameters Major Radius=1.0, Minor Radius=0.25 while performing a boolean add operation with Solid 1.


Solid Boolean operation during primitive creation

This form is used to perform a Solid boolean operation on an existing solid during the creation of a new primitive solid. This is a child form of the parent Create,Solid,Primitive form.


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Creating Solids from Surfaces (Surface Method)

Creating Solids from Two Surfaces

The Surface method with the 2 Surface option, creates solids between two surfaces or solid faces.

Solid Surface Method With 2 Surface Option Example

Creates Solid 1 using the Create/Surface/2 Surface option. The solid is created between Surfaces 2 and 3.


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Creates Solid 1 using the Create/Surface/2 Surface option. The solid is created between Surface 2 and a surface defined by Curves 5 and 6, using the Surface select menu icon listed below.


Creating Solids from Three Surfaces (Surface Method)

The Surface method with the 3 Surface option creates solids that pass through three existing surfaces or solid faces.


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Creates Solid 2 using the Create/Surface/3 Surface option. The solid is created between a face of Solid 1, Surface 2 and a surface defined by Curves 5 and 6 by using the Surface select menu icon listed below.


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Creating Solids from Four Surfaces (Surface Method)

The Surface method using the 4 Surface option creates solids that pass through four existing surfaces or solid faces.


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Creates Solid 2 using the Create/Surface/4 Surface option. The solid is created between a face of Solid 1, Surface 2, a surface defined by Curves 5 and 6 and Surface 3.


Creating Solids with the N Surface Option

The Surface method using the N-Surfaces option creates solids that pass through any number of existing surfaces or solid faces.


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Solid Surface Method with N-Surfaces Option Example

Creates Solid1 using the Create/Surface/N-Surfaces option. The solid is created between Surfaces 2, 7, 8, 9 and 10.


Creating a Boundary Representation (B-rep) SolidThe B-rep method creates boundary represented solids by specifying a list of surfaces or solid faces that form a closed topologically congruent volume. B-rep solids can only be meshed with Patran’s TetMesh. For more information, see Gliding Solids, 347.


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• B-rep Solid

• Building B-rep Solids

Solid B-rep Method Example

Creates Solid 1 using the Create/Solid/B-rep method which is created from Surfaces 2, 3, 4, and 8 through 14. Notice that since Delete Original Surfaces is pressed in, the surfaces are deleted.


Creating a Decomposed SolidThe Decompose method creates solids from two opposing solid faces by choosing four vertex locations on each face and then a solid is created from the two decomposed faces.


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Solid Decompose Method with Face 1 Option Example

Creates Solid 2 by selecting four points on solid face Solid 1.6 and four points on solid face Solid 1.5.


Solid Decompose Method with Face 2 Option Example

Creates Solid 2 by selecting four points on solid face Solid 1.6 and four points on solid face Solid 1.5.


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Creating Solids from FacesThe Face method creates a solid from five or six surfaces or solid faces which define the solid’s exterior faces. The surfaces or faces can be in any order and they can have any parametric orientation, but they must define a valid exterior of a solid.


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Solid Face Method With 6 Faces Example

Creates Solid 1 using the Create/Face method which is created from Surfaces 2 through 7. The option is set to 6 Face.


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Solid Face Method With 5 Faces Example

Creates Solid 1 using the Create/Face method which is created from Surfaces 1 through 5. The option is set to 5 Face.


Creating Solids from Vertices (Vertex Method)The Vertex method creates parametric tri-cubic solids by specifying a list of eight point locations that represent the eight vertices of the new solid. The point locations can be points, vertices, nodes or other point locations provided on the Point select menu.


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Solid Vertex Method Example

Creates Solid 2 using the Create/Vertex method which is created from Points 12 through 15 and Nodes 34, 44, 254 and 264.


Gliding SolidsThe Glide method creates triparametric solids by sweeping a base surface curve along a path defined by a set of director curves or edges.


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Solid Glide Method Example

Creates Solid 1 using the Create/Glide method which is created from Curve 5 for the Director Curve and Surface 2 for the Base Surface. The scale is set to 0.25 and Fixed Glide is pressed in.

Geometry Modeling - Reference Manual Part 2Feature Recognition (Pre-release)

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Feature Recognition (Pre-release)

Feature TypesThe Feature Recognition Tool support the following feature types:

• Circular Hole features.

• Transition features.

• Blends

• Chamfers

The Actions supported for features are: Recognize, Clear, Show, Delete, Edit

The Methods supported for features are: Automatic, Interactive

Feature Definition

The feature has the following attributes:

Name: string identifier, i.e., Hole 1

Parameters: the values defining the feature, i.e.,

• for holes the parameters are radius and depth

• for blends the parameters are radius1 and radius2

• for chamfers the parameters are height1 and height2

Id: the internal id used for storage

Label: the numeric value of the feature name; i.e., if the feature name is Hole 1, the label is 1.

Automatic Recognition

You select the solid list from which the features are to be recognized from the viewport and the corresponding features for which recognition was called is recognized. In case of transition features automatic recognition recognizes all the features with chaining.

Interactive Recognition

You can interactively pick the face (or edge for holes) list from the viewport and only those features which contain the selected faces (or edges for holes) are recognized. Single or compound/chain features can be recognized during interactive recognition.

Overview of the Feature Recognition ModulesThe feature recognition technology integrated in Patran is centered around two modules:

351Chapter 4: Create ActionsFeature Recognition (Pre-release)

Hole module. This module provides recognition of hole features in the input model. It recognizes circular features. It can recognize circular holes which may be blind or thru. Non-circular features like the rectangular holes, cannot be recognized with this module. Every hole feature has two associated attributes namely the radius, and depth. In case of blind holes both these attributes can be modified/edited, but in case of a thru hole only its radius can be modified/edited. During recognition phase the dependency relations between different hole features are also recognized. Subsequent operations on these features require satisfying these dependency relations. For example, if hole 2 is dependent upon hole 1 (parent child relation) then deletion of hole 1 will automatically result in deletion of hole 2. Similar relations apply for editing of dependent features.

Blend/Chamfer module. This module provides recognitions of transition features namely blend features and chamfer features. Two types of blends are recognized – constant radius blends and variable radius blends. Thus each blend has two attributes namely the maximum radius and minimum radius. However in case of constant radius blends the values of these two attributes are same. Similarly a chamfer feature has two attributes which are its slope heights. Transition features such as blends and chamfers are rarely isolated, and are usually connected to other blends/chamfers to form a blend/chamfer chain. Thus automatic recognition by default recognizes blends and chamfers with chaining, whereas, interactive recognition allows features to be recognized as a single feature or a compound or chain feature. Figure below shows a blend chain.


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Limitations

Only one feature type per solid can be recognized and worked on at a time. For example, if you have recognized holes from one solid, then recognize blends on the same solid in the same Patran session, the feature modeler will replace the hole features with the newly recognized blend features for the solid. You can recognize holes for one solid and blends for another solid and the holes and blends will be stored in the feature modeler. All previous edits to the model by editing hole parameters or deleting holes will be saved however.

Solids whose geometry source is Parasolid is the only type supported for Feature Recognition.

Feature Recognition

Recognize Feature Hole Automatic

Recognizes circular features from the selected Solid. It can recognize circular holes that are blind or through. The dependency relations between different holes are also recognized.


Recognize Feature Hole Interactive

Recognizes circular features from the selected Solid Face or Edge . It can recognize circular holes that are blind or through. The dependency relations between different holes are also recognized.


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Recognize Feature Blend Automatic

Recognizes transition features such as Blend features from the selected Solid. It can recognize constant radius and variable radius blends. The dependency relations between different blends are also recognized. Automatic recognition by default recognizes blends with chaining.


Recognize Feature Blend Interactive

Recognizes transition features such as Blend features from the selected Solid Face. It can recognize constant radius and variable radius blends. The dependency relations between different blends are also recognized.


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Recognize Feature Chamfer Automatic

Recognizes transition features such as Chamfer features from the selected Solid. The dependency relations between different chamfers are also recognized.


Recognize Feature Chamfer Interactive

Recognizes transition features such as Chamfer features from the selected Solid Face. The dependency relations between different chamfers are also recognized.


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Edit Hole FeatureEdit the Hole Feature Parameters. The radius and depth parameters for a blind hole or the radius of a through hole can be edited.


Edit Hole Feature

Edit the four selected holes by changing the radius values from 4 and 5 to 8.


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Edit Hole Feature

The four selected hole radii changed from values from 4 and 5 to 8.


Edit Hole Feature using Radius ConstraintEdit the Hole Feature Parameters using a Radius Constraint. The radius and depth parameters for a blind


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hole or the radius of a through hole can be edited.edited.

Edit Hole Feature Using Radius Constraint

Edit the four selected holes by changing the radius values and depth from 3 and 15 to 5 and 5 respectively.


Edit Hole Feature Using Radius Constraint

The four selected holes radii and depths changed from 3 and 15 to 5 and 5 respectively.


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Edit Blend FeatureEdit the Blend Feature Parameters. The radius R1 and radius R2 parameters for a Constant Radius or a


Variable Radius blend can be edited.

Edit Blend Feature

Edit the four selected blends by changing the R1 and R2 radii from 4 and 4 to 3 and 6 respectively.


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Edit Blend Feature

The four selected blends R1 and R2 radii changed from 4 and 4 to 3 and 6 respectively.


Edit Blend Feature using Radius ConstraintEdit the Blend Feature Parameters using a Radius Constraint. The radius R1 and Radius R2 parameters for a Constant Radius or Variable Radius Blend can be edited.


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Edit Blend Feature Using Radius Constraint

Edit the four selected blends by changing the R1 and R2 radii from 5 and 5 to 10 and 10 respectively.


Edit Blend Feature Using Radius Constraint

The four selected blends R1 and R2 radii changed from 5 and 5 to 10 and 10 respectively.


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Edit Chamfer FeatureEdit the Chamfer Feature Parameters. The height H1 and height H2 parameters for a chamfer can be edited.


Edit Chamfer Feature

Edit the three selected Chamfers by changing the H1 and H2 heights from 3 and 3 to 5 and 5 respectively.


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Edit Chamfer Feature

The three selected Chamfers H1 and H2 heights changed from 3 and 3 to 5 and 5 respectively.


Edit Chamfer Feature using Height Constraint


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Edit the Chamfer Feature Parameters using a Height Constraint. The height H1 and height H2 parameters for a chamfer can be edited.

Edit Chamfer Feature Using Height Constraint

Edit the three selected chamfers by changing the H1 and H2 heights from 2 and 2 to 4 and 4 respectively.


Edit Chamfer Feature Using Height Constraint

The three selected chamfers H1 and H2 heights changed from 2 and 2 to 4 and 4 respectively.


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Edit Feature ParametersThe Edit Feature Parameters form allows the feature name and parameters to be displayed and modified for alteration of a model.


When a column of the spreadsheet is selected, the value is copied to the input databox for editing. Once the value is modified, press return to update the selected column with the new parameter definition. When all the desired parameter values are modified, press the OK button to save the changes.

If the Feature Name is changed and the same name is used for multiple feature names, the feature label will be appended to the input name. For example, if you entered “test” for the name of Hole 1 and Hole 2, then the resulting name for Hole 1 will be “test” and the name for Hole 2 will be test 2.

Show Hole FeatureShow the Hole Feature Parameters. The radius and depth parameters and the number of faces for each hole is displayed.


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Show Hole Feature using Radius ConstraintShow the Hole Feature Parameters using a Radius Constraint. The radius and depth parameters and the number of faces for each hole is displayed.


Show Blend FeatureShow the Blend Feature Parameters. The radius R1 and radius R2 parameters and the number of faces for each blend is displayed.


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Show Blend Feature using Radius ConstraintShow the Blend Feature Parameters using a Radius Constraint. The radius R1 and Radius R2 parameters and the number of faces for each blend is displayed.


Show Chamfer FeatureShow the Chamfer Feature Parameters. The height H1 and height H2 parameters and the number of faces for each chamfer is displayed.


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Show Chamfer Feature using Height ConstraintShow the Chamfer Feature Parameters using a Height Constraint. The height H1 and Height H2 parameters and the number of faces for each chamfer is displayed.


Show Feature InformationThe Show Feature Information form allows the parameters of a feature to be displayed.

The spreadsheet shows the following information for each feature selected:

• Feature Name

• Parameter Name 1 and value

• Parameter Name 2 and value

• Number of Faces

Picking a spreadsheet cell will highlight the feature in the Patran secondary highlight color


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Delete Hole FeatureDelete Hole Features.


Delete Hole Feature using Radius ConstraintDelete Hole Features using a Radius Constraint.


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Delete Blend FeatureDelete Blend Features.


Delete Blend Feature using Radius ConstraintDelete Blend Features using a Radius Constraint.


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Delete Chamfer Feature using Height ConstraintDelete Chamfer Features using a Height Constraint.


Delete Chamfer FeatureDelete Chamfer Features.


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Delete Any FeatureDelete any features in the model.


Clear FeatureClear features from the feature modeler derived from a solid without deleting the associated geometry.


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393Chapter 4: Create ActionsCreating Coordinate Frames

Creating Coordinate Frames

Creating Coordinate Frames Using the 3Point MethodThe 3Point method creates a rectangular, cylindrical or spherical coordinate frame by specifying three point locations. The point locations can be points, vertices, nodes or other point locations provided on the Point select menu. For more information, see Overview of Create Methods For Coordinate Frames.

More Help:


• Topology


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Coordinate Frame 3Point Method Example

Creates a cylindrical coordinate frame, Coord 100, using the Create/3Point method. Its origin is located at [0,0,0]; a point on its Z axis is at [0,0,1]; and a point on the R-Z plane is at [0,0,1]. The coordinate values are expressed within the global coordinate frame, Coord 0.

Coordinate Frame 3Point Method Example

Creates a cylindrical coordinate frame, Coord 200. Its origin is located at Point 8; a point on its Z axis is at [x8 y8 2] (which is at the X and Y coordinates of Point 8 and at Z=2); and a point on the R-Z plane is at Point 6.


Creating Coordinate Frames Using the Axis MethodThe Axis method creates a rectangular, cylindrical or spherical coordinate frame by specifying three point locations for the coordinate frame’s origin, at the first, second or third axis and on one of the remaining two axes. The point locations can be points, vertices, nodes or other point locations provided on the Point select menu. See Overview of Create Methods For Coordinate Frames.


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Coordinate Frame Axis Method Example

Creates a rectangular coordinate frame, Coord 100, using the Create/Axis method. Its definition is expressed within the rectangular coordinate frame, Coord 0; its origin is located at [0,0,0]; a point on its X axis is at Point 20; and a point on its Y axis is at Point 12.


Creating Coordinate Frames Using the Euler MethodThe Euler method creates a rectangular, cylindrical or spherical coordinate frame through three specified rotations about the axes of an existing coordinate frame. See Overview of Create Methods For Coordinate Frames.


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Coordinate Frame Euler Method Example

Creates a spherical coordinate frame, Coord 200, using the Create/Euler method. Its definition is expressed within the rectangular coordinate frame, Coord 100; its origin is located at Point 14 and it is rotated 45 degrees about Coord 100’s X axis.


400

Rotation Parameters Subordinate Form Example

The Rotation Parameters subordinate form appears when the Rotation Parameters button is pressed on the Geometry Application Create/Coord/Euler form. See Creating Coordinate Frames Using the Euler Method.

This form allows you to define up to three rotations to be performed about the specified Reference Coordinate Frame axes. The rotations are performed in sequence from top to bottom on the form.


Creating Coordinate Frames Using the Normal MethodThe Normal method creates a rectangular, cylindrical or spherical coordinate frame with its origin at a point location on a specified surface or solid face, and its axis 3 direction normal to the surface or face. The coordinate frame’s axis 1 direction can be aligned with the surface’s or face’s parametric

direction, and its axis 2 direction will be aligned with the direction or visa versa. See Overview of

Create Methods For Coordinate Frames for more information.

You can plot the parametric and directions by pressing the Parametric Direction button on the

Geometric Properties form under the Display/Display Properties/Geometric menu.

1

2

1 2


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• Display>Named Attributes (p. 400) in the Patran Reference Manual

Coordinate Frame Normal Method Example

Creates a rectangular coordinate frame, Coord 1, using the Create/Normal method whose Z axis is normal to Surface 2 and its origin is at Point 16. Notice that Coord 1’s X and Y axis are aligned with Surface 2’s

and directions. 1 2


Coordinate Frame Normal Method On a Face Example

Creates rectangular coordinate frame, Coord 2 at Point 17, whose Z axis is normal to the top face of Solid 1.


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Creating Coordinate Frames Using the 2 Vector MethodThe 2 Vector method creates a rectangular, cylindrical or spherical coordinate frame with its origin at the designated location. Two of the through coordinate frame axes are defined using existing vectors; their directions are imposed at the selected origin and the new coordinate frame is then created.


Creating Coordinate Frames Using the View Vector MethodThe View Vector method creates a rectangular, cylindrical, or spherical coordinate frame at the designated origin, using the Euler angles that define the current model orientation within the graphics viewport.


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407Chapter 4: Create ActionsCreating Planes

Creating Planes

Creating Planes with the Point-Vector MethodThe Point-Vector method creates planes at a point and normal to a vector.

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Point-Vector Method Example

Creates a plane at a point and normal to a vector.

Geometry Modeling - Reference Manual Part 2Creating Planes

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Creating Planes with the Vector Normal MethodThe Vector Normal method creates Planes whose normal is in the direction of the specified vector and crosses the vector at a specified offset.


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Vector Normal Option Example

Creates a plane from Vector 1. The normal of the plane is parallel to the Vector.


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Creating Planes with the Curve Normal Method

Creating Planes with the Curve Normal Method - Point Option

The Point on Curve method using the Point option creates Planes normal to a tangent vector of a point along a curve. The plane centroid will be the point location on the curve.


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Point Option Example

Creates a plane whose normal is parallel to the tangent of Curve 1 on the location where Point 3 is projected on the curve.


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Creating Planes with the Curve Normal Method-Parametric Option

The Point on Curve method using the Parametric option creates Planes that are normal to a specified curve at a parametric position along the curve. The plane centroid will be the parametric position along the curve.


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Parametric Option Example

Creates a plane on Curve 1 at the specified parametric location. Its normal is parallel to the tangent of Curve 1 at that location.


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Creating Planes with the Plane Normal MethodThe Plane Normal method creates a plane normal to an existing plane. The line defined by the projection of the new plane onto the existing plane is defined by selecting a vector; this vector is projected normally onto the existing plane. The new plane’s normal direction is defined by the vector cross product of the existing plane normal by the projected vector.


Creating Planes with the Interpolate Method

Creating Planes with the Interpolate Method - Uniform Option

The Interpolate method creates Planes whose normals are in the direction of the curve tangents at the interpolating points on the curve. Uniform option will space the planes along the curve based on the equal arc lengths or equal parametric values upon the user’s choice.


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Plane Interpolate Example

Creates planes on curve 1 at the interpolating points. The plane’s normals are parallel to the tangents of Curve 1 at each location.


Creating Planes with the Interpolate Method - Nonuniform Option

The Interpolate method creates Planes whose normals are in the direction of the curve tangents at the interpolating points on the curve. Nonuniform option will space the planes along the curve based on the space ratio applied on the arc length or the parametric values upon the user’s choice.


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Creating Planes with the Least Squares Method

Creating Planes with the Least Squares Method - Point Option

The Least Squares method using the Point option creates Planes that are a least squares fit to a set of points that are not co-linear.


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Creates a plane based on the least squares calculated from Point 1:4.


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Creating Planes with the Least Squares Method - Curve Option

The Least Squares method using the Curve option creates Planes that are a least squares fit to a non-linear curve.


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Curve Option Example

Creates a plane based on the least squares calculated from Curve 1.


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Creating Planes with the Least Squares Method - Surface Option

The Least Squares method using the Surface option creates Planes that are a least squares fit to a surface.


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Surface Option Example

Creates a plane based on the least squares calculated from Surface 1.


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Creating Planes with the Offset MethodThe Vector Normal method creates Planes whose normal is in the direction of the specified vector and crosses the vector at a specified offset.


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Offset Method Example

Creates planes, which are parallel to Plane 1 but have a offset of 1.0 from each other.


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Creating Planes with the Surface Tangent Method

Creating Planes with the Surface Tangent Method - Point Option

The Tangent method using the Point option creates Planes that are tangent to a specified surface at a specified point on the surface. The plane centroid will be the point location on the surface.


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Creates a plane which is tangent to Surface 1 at Point 5.


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Creating Planes with the Surface Tangent Method - Parametric Option

The Tangent method using the Parametric option creates Planes that are tangent to a specified surface at a parametric position on the surface. The plane centroid will be the tangent point on the surface.


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Parametric Option Example

Creates a plane which is tangent to Surface 1 at the specified parametric locations.


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Creating Planes with the 3 Points MethodThe 3 Point method creates Planes which pass through three specified points that are not co-linear. The plane centroid will be average of the first point.


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3 Points Method Example

Creates a plane from Point 1:3.


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433Chapter 4: Create ActionsCreating Vectors

Creating Vectors

Creating Vectors with the Magnitude MethodThe Magnitude method creates Vectors from a specified vector magnitude, direction and base point. The base point can be expressed by cartesian coordinates or by an existing vertex, node or other point location provided by the Point select menu.

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Magnitude Example

Creates a vector based at point 1 and directing along the X axis. The vector has a magnitude of 1.0.

Creating Vectors with the Interpolate Method

Between Two Points

The Interpolate method using the Point option will create n points of uniform or nonuniform spacing between a specified pair of point locations, where n is the number of interior points to be created. The point location pairs can be existing points, vertices, nodes or other point location provided by the Point select menu.


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Creating Vectors with the Intersect MethodThe Intersect method creates Vectors from the intersections of pairs of Planes. The origins of the two planes will be projected onto the intersection line to determine the base and tip of the resulting vector. If the base and tip are not unique, the tip will be assumed.


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Intersect Example

Creates a vector along the intersection of Plane 1 and Plane 2.


Creating Vectors with the Normal Method

Creating Vectors with the Normal Method - Plane Option

The Normal method using the Plane option creates Vectors from normal vectors to a Plane; originating at the plane and passing through a point. The tip point can be expressed by cartesian coordinates or by an existing vertex, node or other point location provided by the Point select menu.


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Plane Option Example

Creates a vector which is directing along the normal of Plane 1.


Creating Vectors with the Normal Method - Surface Option

The Normal method using the Plane option creates Vectors from normal vectors to a Plane. The base point can be expressed by cartesian coordinates or by an existing vertex, node or other point location provided by the Point select menu.


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Surface Option Example

Creates a vector which is directing along the normal of Surface 1 at Point 5.


Creating Vectors with the Normal Method - Element Face Option

The Normal method using the Element Face option creates Vectors from normal vectors to an Element Face. The base point of the vector will be the element face centroid by default, but a node on the element face may also be specified.


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Element Face 2D Option Example

Creates a vector along the normal of the element face at Node 6.


Element Face 3D Option Example

Creates a vector along the normal of the element face at Node 2.


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Creating Vectors with the Product MethodThe Product method creates vectors of the cross products of two existing vectors. The base point of the created vector will be the base point of the first vector.


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Product Example

Creates Vector 3, which is the cross product of Vector 1 and Vector 2.


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Creating Vectors with the 2 Point MethodThe 2 Point method creates vectors between two existing point locations. The point locations can be existing points, vertices, nodes, or other point locations provided on the Point select menu.


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2 Point Option Example

Creates a vector starting from Point 1 and ending at Point 2.


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449Chapter 4: Create ActionsCreating P-Shapes

Creating P-Shapes

RectangleThe rectangle is defined by an origin point p1, a corner point p2 along direction-1 or the u-direction, and a corner point p3 along direction-2 or the v-direction. All points are given with respect to the Reference Coordinate Frame. The point p3 is constrained to be orthogonal to the vector p1-p2 and will be corrected as necessary.

QuadrilateralA Quadrilateral is defined by an origin point p1, and corner points p2 in direction-1 (u-direction), and p3 in direction-2 (v-direction), and an opposite corner p4 in the Reference Coordinate Frame.

Geometry Modeling - Reference Manual Part 2Creating P-Shapes

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TriangleA triangle is defined by an origin point p1, and corner points p2 in direction-1 (u-direction) and p3 in direction-2 (v-direction). In Patran, the triangle is created as a bi-parametric surface and has one degenerate side at the origin point p1.


DiscA disc is defined by an external and internal diameter. It is defined in a Reference Coordinate Frame with an Axis of Revolution shown as the vector p1-p2. The Angle Origin Vector is shown as vector p1-p3 and the start and end angle are measured in degrees circumferentially from that vector.


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CylinderA cylinder is defined by a diameter in a Reference Coordinate Frame with an Axis of Revolution shown as the vector p1-p2. This vector also gives the height of the cylinder. The Angle Origin Vector is shown as vector p1-p3 and the start and end angle are measured in degrees circumferentially from that vector.


ConeA cone is defined by diameters at the base and apex in a Reference Coordinate Frame with an Axis of Revolution shown as the vector p1-p2. This vector also gives the height of the cone. The Angle Origin Vector is shown as vector p1-p3 and the start and end angle are measured in degrees circumferentially from that vector.


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SphereA sphere is defined by a diameter in a Reference Coordinate Frame with an Axis of Revolution shown as the vector p1-p2. The Angle Origin Vector is shown as vector p1-p3 and the start and end angle are measured in degrees circumferentially from that vector.

The sphere may be truncated at the poles. The base truncation gives the height of the sphere from the equator to the “bottom” of the sphere. If the negative truncation distance is equal to the radius, then the sphere is not truncated. The same applies to the apex truncation. Note that a negative truncation distance measures “below” the equator while a positive truncation measures “above” the equator.


ParaboloidA paraboloid is defined by a diameter in a Reference Coordinate Frame with an Axis of Revolution shown as the vector p1-p2. This vector also gives the un-truncated height of the paraboloid. The Angle Origin Vector is shown as vector p1-p3 and the start and end angle are measured in degrees circumferentially from that vector.

The paraboloid may be at the apex and also at the base. Both truncations are measured from the apex of the paraboloid.


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Five-Sided BoxA Five-sided box is defined as a solid, but is an open-shell meaning that it is a connected set of five surfaces which is not closed. The five-sided box is defined with dimensions dx, dy, and dz in the x, y, and z directions at the global origin. The face that is "missing" from the 5-sided box is the z+ face. At the time of creation, a local coordinate frame is used to create the solid at a user-prescribed location. The local coordinate frame is represented by an axis which defines the local origin of the solid at the axis begin point and the x-direction of the solid. The y-direction is defined by a vector. The z-direction is defined ortho-normal to the x-y plane.


Six-Sided BoxA Six-sided Box is a parameterized solid defined with dimensions dx, dy, and dz in the x, y, and z directions at the global origin. At the time of creation, a local coordinate frame is used to create the solid at a user-prescribed location. The local coordinate frame is represented by an axis which defines the local origin of the solid at the axis begin point and the x-direction of the solid. The y-direction is defined by a vector. The z-direction is defined ortho-normal to the x-y plane.


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459Chapter 4: Create ActionsEdit P-Shapes

Edit P-ShapesThis form is used to edit P-Shapes by their parameters. One or more P-Shapes of the same type may be modified. A P-Shape may be selected by its label. The P-Shapes listed in the listbox may be filtered by name or by type, e.g., Rectangle, Triangle, etc. P-Shapes which are listed in the listbox may be displayed on the screen using the “Show P-Shape” button and the display is reset using the “Reset” button.

P-Shapes can also be selected off the screen using the “Select P-Shape(s)” select data box . Since different types of P-Shapes may be selected in either the listbox or in the select data box, the “Filter for P-Shape(s)” button is used to isolate one type of P-Shape.

If only entity is selected for edit, then you can edit the P-Shape Label. The parameters to edit are identical to the Create P-Shape forms for each geometry type. If multiple entities are selected, certain parameters may not be editable such as the Axis of Revolution for cones (spheres, paraboloids) since modifying that parameter to be the same will transform all cones edited to be in the same location.

Geometry Modeling - Reference Manual Part 2Edit P-Shapes

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Chapter 5: Delete ActionsGeometry Modeling - Reference Manual Part 2

5 Delete Actions

Overview of the Geometry Delete Action 462

Deleting Any Geometric Entity 463

Deleting Points, Curves, Surfaces, Solids, Planes or Vectors 464

Deleting Coordinate Frames 466

Geometry Modeling - Reference Manual Part 2Overview of the Geometry Delete Action

462

Overview of the Geometry Delete ActionThe Geometry Application Delete action can remove any or all geometric entities from the database. Objects that are available for deletion are listed in Table 5-1.

Auto Execute Is Off By Default

By default, the Auto Execute toggle is OFF. For more information, see Auto Execute (p. 26) in the Patran Reference Manual.

Using the Abort and Undo Buttons

When the Delete action form starts to execute, you may press the Abort key at any time to halt the delete process. You may also press the Undo button immediately after the Delete action completes to restore the deleted entities back to the database. See System Tool Palette (p. 14) in the Patran Reference Manual for more information.

Table 5-1 Geometry Delete Action Objects and Descriptions

Object Description

Any Deletes different types of geometric entities at the same time.

Point Deletes any number of points.

Curve Deletes any number of curves.

Surface Deletes any number of surfaces.

Solid Deletes any number of solids.

Coord Deletes any number of user defined coordinate frames.

463Chapter 5: Delete ActionsDeleting Any Geometric Entity

Deleting Any Geometric EntitySetting the Object menu to Any deletes any number of points, curves, surfaces, solids or coordinate frames (except the global coordinate frame, Coord 0) from the database. You can also delete geometric entities by using the Group/Delete menu.

Tip: More Help:


• Group>Delete (p. 297) in the Patran Reference Manual

Geometry Modeling - Reference Manual Part 2Deleting Points, Curves, Surfaces, Solids, Planes or Vectors

464

Deleting Points, Curves, Surfaces, Solids, Planes or VectorsSetting the Object menu to Point, Curve, Surface, Solid, Plane or Vector removes any number of specified points, curves, surfaces, solids, planes or vectors from the database.

465Chapter 5: Delete ActionsDeleting Points, Curves, Surfaces, Solids, Planes or Vectors

Tip: More Help:

• The List Processor (p. 43) in the Patran Reference Manual

• Group>Delete (p. 297) in the Patran Reference Manual

Geometry Modeling - Reference Manual Part 2Deleting Coordinate Frames

466

Deleting Coordinate FramesSetting the Object menu to Coord removes any number of specified user defined coordinate frames from the database The global rectangular coordinate frame, Coord 0, cannot be deleted. Also, a coordinate frame will not be deleted if it is being referenced as a Nodal Reference Coordinate Frame or Analysis Coordinate Frame, elsewhere in the model.

Tip: More Help:

• The List Processor (p. 43) in the Patran Reference Manual


• Node Coordinate Frames (p. 47) in the Reference Manual - Part III

Chapter 6: Edit ActionsGeometry Modeling - Reference Manual Part 2

6 Edit Actions

Overview of the Edit Action Methods 468

Editing Points 470

Editing Curves 472

Editing Surfaces 518

Editing Solids 589

Editing Features 632

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Overview of the Edit Action MethodsObject Method Description

Point • Equivalence • Finds groups of points which are within global model tolerances of each other and for each group, equivalences the points into one point.

Curve • Break • Breaks curves into n+1 curves at either a point location or at a parametric coordinate location.

• Blend • Creates curves from two or more curves or edges by forcing a first derivative continuity across the boundaries.

• Disassemble • Creates curves that represent a specified chained curve.

• Extend • Extends or lengthens one curve or edge or a pair of curves or edges, either through a straight line extension, or through a continuous curvature.

• Merge • Creates one or more curves from an existing set of curves or edges. Some of the original curvature may be lost.

• Refit • Creates Uniformly parameterized Piecewise Cubic curves from existing curves.

• Reverse • Redefines the connectivity of a curve or edge by reversing the curve’s or edge’s positive parametric direction.

• Trim • Shortens the length of a curve or edge at either a point location or a parametric coordinate location on the curve.

Surface • Break • Breaks a surface or a solid face into two or four smaller surfaces at either a point, curve or surface location, or at a parametric coordinate location on the surface.

• Blend • Creates surfaces from two or more surfaces or solid faces by forcing a first derivative continuity across its boundaries. A parametric green surface is required for this operation to work.

• Disassemble • Creates surfaces that represent the specified B-rep solid.

• Edge Match • Recreates a specified surface either by closing a gap between it and another adjacent surface; or by creating an additional vertex and converting the surface into a trimmed surface.

• Extend • Extends or lengthens a surface: by a percentage in the U and/or V parametric directions, to its intersection with a curve, plane, point or another surface, or by a fixed length. Also extends a pair of surfaces to their intersection.

• Refit • Creates a non-uniformly parameterized network of bicubic patches from existing surfaces.

• Reverse • Redefines the connectivity of a surface or solid face by reversing the surface’s or face’s positive parametric directions.

469Chapter 6: Edit ActionsOverview of the Edit Action Methods

• Sew • Combines Edit, Point, Equivalence and Edit, Surface, Edge Match functionality to equivalence surface vertices and merge edges.

Solid • Break • Breaks a solid into two, four or eight smaller solids either at a point, curve or surface location, or at a parametric coordinate location.

• Blend • Creates solids from two or more solids by forcing a first derivative continuity across its boundaries.

• Disassemble • Creates surfaces that represent a specified B-rep solid.

• Refit • Creates uniformly parameterized Piecewise Cubic solids from existing solids.

• Reverse • Redefines the connectivity of a solid by reversing the solid’s positive parametric directions.and moving the location of the parametric origin.

Feature • Suppress • Displays the list of CAD features associated with the geometry that can be suppressed from the geometric model

• Unsuppress • Displays the list of CAD features associated with the geometry that can be unsuppressed from the geometric model.

• Parameters • Displays the list of CAD features associated with the geometry whose parameters can be edited to be used to regenerate the geometric model based on the new parameter values.


Geometry Modeling - Reference Manual Part 2Editing Points

470

Editing Points

Equivalencing PointsThe Point Equivalence method finds groups of points which are within global model tolerance of each other and for each group and equivalences the points into one point.

Editing Point Equivalence Method Example

Equivalences points 5 and 6 resulting in point 5 at the mid-point between points 5 and 6.

471Chapter 6: Edit ActionsEditing Points

Geometry Modeling - Reference Manual Part 2Editing Curves

472

Editing Curves

Breaking Curves

Breaking a Curve at a Point

The Break method with the Point option creates n+1 curves by breaking an existing curve or edge at one or more point locations. The point locations can be defined by either existing points, nodes, vertices, curve/curve intersections, or curve/surface intersections. Also, the break point location does not have to lie on the curve or edge.

473Chapter 6: Edit ActionsEditing Curves

Tip: More Help:

• Select Menu (p. 33) in the Patran Reference Manual, Part 1: Basic Functions

• Topology (p. 10)

Curve Break Method At a Point Example

Creates Curves 2 and 3 by breaking Curve 1 at Point 2. Notice that Delete Original Curves is pressed in and Curve 1 is deleted.


474

Curve Break Method Between Two Points Example

Creates Curves 1 and 2 by breaking a curve defined by Points 1 and 2 (by using the Curve select menu icon listed below) at the break location of Node 1. Notice that Node 1 does not have to be colinear with Points 1 and 2.


Curve Break Method At An Edge Example

Creates Curves 1 and 2 by breaking an edge of Surface 1 (using the Curve select menu icon listed below) at the break location defined by Node 1.


476

Breaking a Curve at a Parametric Location

The Break method with the Parametric option creates two curves from an existing curve or edge, at the curve’s parametric coordinate location, where has a range of .1 u 1 0 1 1


More Help:


• Topology

• Connectivity


478


Curve Break Method At a Parametric Location Example

Creates Curves 2 and 3 by breaking Curve 1 at . Notice that Delete Original Curves is pressed

in and the Parametric Direction is turned ON.

1 0.25=


Curve Break Method At a Parametric Location On An Edge Example

Creates Curves 1 and 2 by breaking an edge of Surface 1 (by using the Curve select menu icon listed below) at .1 0.25=


480

Breaking a Curve at a Plane Location

The method breaks a curve with a plane. The curve will be broken at each intersection point with the plane.


Tip: More Help:


• Topology

• Connectivity



482

Blending a CurveThe Blend method creates a set of parametric cubic curves from an existing set of two or more curves or edges by enforcing a first derivative continuity across its boundaries. The set of existing curves or edges must be connected.

Tip: More Help:



• Topology



Curve Blend Method At Weighting Factor = 1.0 Example

Creates Curves 6 through 10 by equally blending Curves 1 through 5. Notice that Delete Original Curves is pressed in.


484

Curve Blend Method At Weighting Factors Other Than 1.0 Example

This example is the same as the previous example, except that four weighting factors are used for the four curve pairs: 1e-6, 1.0, 1.0, 1e6.


Disassembling a Chained CurveThe Disassemble method operates on one or more chains (composite curves) and breaks them into the original curves that composed the chain. A chained curve can be created by using Geometry Application’s Create/Curve/Chain form. Chained curves are usually used in Patran for creating trimmed surfaces.


486

Tip: More Help:

• Select Menu (p. 33) in the Patran Reference Manual, Part 1: Basic Functions

• Trimmed Surfaces (p. 20)

• Creating Chained Curves (p. 131)

• Creating Trimmed Surfaces (p. 277)


Curve Disassemble Method Example

Creates Curves 8 through 13 from chained Curve 7. Notice that Delete Original Curves is pressed in and Curve 7 is deleted.


488

Extending Curves

Extending a Curve With the 1 Curve Option

The Extend method with the 1 Curve option extends one or more curves which start at either the beginning or the end of an existing curve or edge, and moves in the tangent direction for a defined length.


You can either extend curves in a straight line or maintain the same curvature as the existing curve or edge.


490


Tip: More Help:


• Topology

• Understanding the List Processor (p. 776) in the Patran Reference Manual

Curve Extend Method For One Curve Example

Extends curve 1 in a straight line by an actual length of 1.0.


492

Curve Extend Method For One Curve Example

This example is the same as the previous example, except Continuous Curvature is pressed in, instead of Straight Line, and Fraction of Original is pressed in based on a value of 1.5.


Curve Extend Method For One Edge Example

Creates Curve 1 by extending it from an edge of Surface 1 (by using the Curve select menu icon listed below). Both Straight Line and Actual are pressed in, with a length of 1.0 entered.


494

Extending a Curve Using the Through Points Type

The Extend method with the 1 Curve option using the Through Points switch modifies one curve by extending the curve through N-points.


Tip: More Help:


• Topology



496

Curve Extend Method For Through Points Example

Extends Curve 1 by passing through the selected screen points.


Extending a Curve Using the Full Circle Type

The Extend method with the 1 Curve option using the Full Circle switch creates one curve by extending the curve to a full circle, given the start, end, or interior point of the curve. If the curve has zero radius of curvature, a circle will not be created.


498

Tip: More Help:


• Topology



Curve Extend Method For Full Circle Example

Extends Curve 1 to a full circle by selecting Curve 1 and then Point 1.

Extending a Curve With the 2 Curve Option

The Extend method with the 2 Curve option extends a set of curves in a straight line by extending them from two existing curves or edges. Patran will extend the specified endpoints to where the two curves


500

will intersect. If the distance from the intersection to the endpoint of one of the existing curves, is within a distance of the Global Model Tolerance, then Patran will extend only one curve instead of two. (The Global Model Tolerance is defined on the Global Preferences form under the Preferences/Global menu).

Tip: More Help:


• Topology



Curve Extend Method For Two Curves Example

Extends Curves 1 and 2 to their point of intersection.

Curve Extend Method For A Curve and An Edge Example

Creates Curve 3 and extends Curve 1 by extending them from Curve 1 and an edge of Surface 1 by using the Curve select menu icon listed below.


502

Merging Existing CurvesThe Merge method creates one or more curves from an existing set of curves or edges. The shape of the new curves, relative to the existing curves or edges, will be preserved to the extent possible, but, in general, some detail will be lost. The existing curves or edges must be connected.


Tip: More Help:


• Parameterization

• Topology




504

Curve Merge Method Example

Creates Curve 6 by merging Curves 1 through 5. Notice that Delete Original Curves is pressed and Curves 1 through 5 are deleted.


This example is the same as the previous example, except that the merge tolerance is 0.00001.



Creates Curves 6 through 8 from merging Curves 1 through 5.


506

Refitting Existing CurvesThe Refit method using the Uniform option creates uniformly parameterized Piecewise Cubic curves from existing curves. The number of piecewise cubic segments per curve is input as the refit parameter.


Tip: More Help:



• Topology



508


Reversing a CurveThe Reverse method redefines the connectivity of an existing set of curves or edges by reversing the positive direction of the curves or edges. You can plot the curve’s direction by selecting the

Parametric Direction toggle on the Geometric Properties form found under the menus Display/Display Properties/Geometric.

1 1


Tip: More Help:


• Topology

• Connectivity



510

Curve Reverse Method Example

This example reverses Curves 6, 7 and 8. Notice that the parametric direction is displayed for the curves.

Curve Reverse Method With Associated Elements Example

This example is the same as the previous example, except Curves 7, 8 and 9 have associated bar elements. Although the node IDs are not reversed, Patran internally reverses the bar elements’ connectivities. For example, for Bar 1 the nodes are stored as Nodes 2 and 1, instead of 1 and 2.


Trimming Curves

Trimming a Curve With the Point Option

The Trim method with the Point option modifies an existing set of curves by trimming them at a specified point location along each curve. The trim point can be defined by either existing points, nodes, curve/curve intersections, or curve/surface intersections. You cannot trim existing edges.


512

Tip: More Help:


• Topology

Curve Trim Method At a Point Example

Trims Curve 9 at Point 9, with Point 9 cursor selected in the Curve/Point List as end of the curve to discard or trim off.


Curve Trim Method At a Point Example

Trims Curve 9 at the intersection of Curves 9 and 10 by using the Point select menu icon listed below for the Trim Point List. Point 8 is cursor selected for the Curve/Point List as the end of the curve to trim.


514

Trimming a Curve Using the Parametric Option

The Trim method using the Parametric option modifies an existing set of curves by trimming them at a specified parametric coordinate location, where has a range of . You cannot trim existing

edges.

1 1 0 1 1


Tip: More Help:


• Topology

• Connectivity



516

Curve Trim Method At a Parametric Location Example

Trims Curve 9 at , where Point 8 is cursor selected as the end of the curve to trim.

Curve Trim Method At a Parametric Location Example

This example is the same as the previous example, except Point 1 instead of Point 8 is cursor selected as the end of the curve to trim in the Curve/Point List box.

1 u 0.75=

Geometry Modeling - Reference Manual Part 2Editing Surfaces

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Editing Surfaces

Surface Break Options

Breaking a Surface With the Curve Option

The Break method with the Curve option creates two surfaces by breaking a surface or solid face at a curve location.The curve location does not have to lie on the surface, but it must intersect on opposite edges of the surface or face. The curve location can be a curve, an edge or other curve locations provided on the Curve select menu.

519Chapter 6: Edit ActionsEditing Surfaces

Tip: More Help:


• Topology

Surface Break Method At a Curve Example

Breaks Surface 1 at Curve 3. Notice that Curve 3 does not lie on Surface 1. Instead, Patran projects the curve break location on the surface. Also, Delete Original Surfaces is pressed in and Surface 1 is deleted.


520

Surface Break Method At Two Points Example

This example is the same as the previous example, except the curve break location is defined by Points 8 and 9 using the Curve select menu icon listed below.


Surface Break Method At a Curve on a Face Example

Breaks a face of Solid 1 using the Surface select menu icon listed below, at the break location of Curve 1.


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Breaking a Surface With the Surface Option

The Break method with the Surface option creates two surfaces by breaking a surface or solid face at a surface location.The surface break location must intersect the surface or face on opposite edges. The surface break location can be a surface or a solid face.


Tip: More Help:


• Topology

Surface Break Method At a Surface Example

Creates Surface 4 and 5 by breaking Surface 1 in half with the break location of Surface 3.


524

Breaking a Surface With the Plane Option

This method breaks a surface with a plane. The surface will be broken along its intersection with the plane.


Tip: More Help:


• Topology

Breaking a Surface With the Plane Option Example

Creates Surfaces 3 and 4 by breaking Surface 2 in half with the break location of Plane 1.


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Breaking a Surface With the Point Option

The Break method with the Point option creates two or four surfaces by breaking an existing surface or solid face defined at a point location. If the point is on an edge, then two surfaces are created. If the point is located on the interior, then four surfaces are created. The point location can be a point, a node, a vertex, a curve/curve intersection or a curve/surface intersection.


Tip: More Help:


• Topology

Surface Break Method At a Point Example

Breaks Surface 1 into four Surfaces at Point 5. Notice that Delete Original Surfaces is pressed and Surface 1 is deleted.


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Surface Break Method At a Point Example

This example is the same as the previous example, except that the break location is at Point 4 instead of Point 5, and Surfaces 2 and 3 are created instead of four surfaces.


Surface Break Method At a Vertex Example

Breaks Surface 1 along the diagonal into Surfaces 2 and 3 at Point 1 which is located at the vertex of Surface 1.


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Breaking a Surface Using the 2 Point Option

The Break method using the 2 Point option creates two surfaces by breaking an existing surface or solid face defined by two point locations. The point locations must lie on opposite edges of the surface or face. The point locations can be points, nodes, vertices, curve/curve intersections, or curve/surface intersections.


Tip: More Help:


• Topology

Surface Break Method At 2 Points Example

Breaks Surface 1 into Surfaces 2 and 3 defined by Point 5 and Node 1. Notice that Delete Original Surfaces is pressed in and Surface 1 is deleted.


532

Breaking a Surface With the Parametric Option

The Break method with the Parametric option creates two surfaces from an existing surface or solid face. The break location is defined at the surface’s or face’s parametric or coordinate location, where

has a range of and has a range of .

1 2 1

0 1 1 2 0 2 1


Tip: More Help:


• Topology

• Connectivity



534

Surface Break Method At Parametric Location u=0.25 Example

Breaks Surface 1 into Surfaces 2 and 3 at . Notice that Delete Original Surfaces is pressed

and Surface 1 is deleted and that the parametric direction is displayed.

Surface Break Method At Parametric Location v=0.25 Example

This example is the same as the previous example, except that the break location is at .

1 u 0.25=

2 v 0.25=


Surface Break Method On a Face At Parametric Location v=0.25 Example

Breaks a face of Solid 1 by using the Surface select menu icon listed below at .2 v 0.25=


536

Blending SurfacesThe Blend method creates a set of parametric bi-cubic surfaces from an existing set of two or more surfaces or solid faces by enforcing a first derivative continuity across its boundaries. The set of existing surfaces or faces must share at least one edge with another surface or face in the set.


Tip: More Help:


• Topology


Note: A parametric green surface is required for this operation to work.


538

Surface Blend Method Example

Blends Surfaces 1, 5, 3 and 4 with a default weight factor of 0.5 applied to all surface edges.

Surface Blend Method Example

Blends Surfaces 1 through 4 with a weighting factor of 1.0 applied to two edges (highlighted in the “Before” picture).


Disassembling Trimmed SurfacesThe Disassemble method operates on one or more trimmed surfaces and creates the parent surface that has the same curvature as the trimmed surface. A trimmed surface can be created either by using the Geometry Application’s Create/Surface/Trim form or by using the Create/Surface/Planar Trim form.


540

Tip: More Help:



• Creating Trimmed Surfaces


Surface Disassemble Method Example

Operates on Surface 2 which is a general trimmed surface. Surface 3 is the new parent surface. Notice that new curves associated with Surface 2 are also created.

Surface Disassemble Method Example

Operates on Surface 1 which is a planar trimmed surface. Notice that the new parent surface, Surface 2, is also planar and that new curves associated with Surface 1 are created.


542

Editing Edges from Surfaces

Removing Edges from Surfaces with Edge Option

With this form you can remove a given edge of a trimmed surface. This process differs from the vertex removal function which was topological in nature. This operation is both topological and geometrical in that the shape of the trimmed surface will be altered as well as the topology. The edges adjacent to the


removed edge will be extended until they intersect. This intersection must take place within the domain of the parent surface.

Removing Edges from Surfaces with Edge Length Option

With this form you can automatically remove all edges whose length is less than a specified value.


544

Adding Edges from Surfaces

With this form you can automatically add edges to a surface.


Replacing Edges from Surfaces

With this form you can automatically replace edges on a specified surface with an existing curve.


546

Matching Surface Edges

Matching Surface Edges with the 2 Surface Option

The Edge Match method with the 2 Surface option recreates the second surface of a specified pair that


share two common vertices but has a gap or unmatched edges. The gap must be less than 10 times the Global Model Tolerance or else Patran will not close the gap. The existing pair of surfaces or faces do not need to have matching parametric and orientations. This method is useful for correcting

topologically incongruent surface pairs so that they are congruent before you mesh. Also see Matching Adjacent Surfaces, 269.

Tip: More Help:


• Topology

• Topological Congruency and Meshing

1 2


548

Surface Edge Match Method Example

Edits Surface 2 which is specified as the second surface of the pair and closes the gap between Surfaces 1 and 2.

Surface Edge Match Method Example

This example is the same as the previous example, except Surface 1 is specified as the second surface of the surface pair.


Matching Surface Edges with the Surface-Point Option

The Edge Match method with the Surface-Point option recreates a specified surface as a trimmed surface that includes an additional cursor defined vertex point. This method is useful for correcting topologically incongruent pairs of surfaces so that they are congruent before you mesh.


550

Tip: More Help:


• Topology


Surface Edge Match Method With Surface-Point Example

Recreates Surface 1 which was a parametric bi-cubic surface, into a trimmed surface which has the vertices Points 1, 2, 3, 4 and 5 so that Surface 1 is congruent with Surfaces 2 and 3. The additional vertex


specified in the Point List was cursor selected at Point 5 by using the Vertex select menu icon listed below.

Extending Surfaces

Extending Surfaces with the 2 Surface Option

This form is used to extend two surfaces to their line of intersection.


552

Tip: More Help:


Extending a Surface With the 2 Surface Option Example

Extend surface 1 to the line of intersection of surface 2.


Extending Surfaces to a Curve

This form is used to extend a surface to an intersecting curve.


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Tip: More Help:


Extending a Surface to a Curve Example

Extend Surface 1 to the edge of Surface 2.


Tip: More Help:


Extending Surfaces to a Plane

This form is used to extend a surface to an intersecting plane.


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Tip: More Help:


Extending a Surface to a Plane Example

Extend Surface 1 to Plane 1.


Extending Surfaces to a Point

This form is used to extend a surface to an intersecting point.


558

Extending a Surface to a Point Example

Extend Surface 1 to Point 1.


Extending Surfaces to a Surface

This form is used to extend a surface to an intersecting surface.


560

Tip: More Help:



Extending a Surface to a Surface Example

Extend Surface 1 to the line of intersection of Surface 2 and break Surface 2 at the line of intersection to create Surface 3 and 4, then delete Surface 2.


562

Extending Surfaces with the Percentage Option

This form is used to extend a surface by a percentage in the U and/or V parametric directions.


Tip: More Help:


Extending a Surface With the Percentage Option Example

Extend Surface 1 by 100% in the U direction starting at U-Max = 1 and shrink Surface 1 by 50% in the V direction starting at V-Max=1.


564

Extending Surfaces with the Fixed Length Option

This form is used to extend a surface by a fixed length.


Tip: More Help:


Extending a Surface With the Fixed Length Option Example

Extend Surface 1 by a fixed length of 5.0 units in the X direction.


566

Refitting SurfacesThe Refit method creates a non-uniformly parameterized network of bicubic patches from existing surfaces. The Refit Tolerance is input as the refit parameter.


Tip: More Help:


• Topology



568

Reversing SurfacesThe Reverse method redefines the connectivity of an existing set of surfaces or solid faces by exchanging the positive and directions of the surfaces or faces. You can plot the and directions for the

surfaces by pressing the Show Parametric Direction toggle on the Geometric Attributes form found under the menu Display/Geometry.

Tip: More Help:


• Topology

1 2 1 2


• Connectivity


• Showing Surface Attributes

Surface Reverse Method Example

Reverses the parametric and directions for Surface 1. Notice that the parametric directions are

displayed on the surfaces. Also, notice that Auto Execute is not on so that you can press the Draw Normal Vectors button without executing the form.

1 2


570

Sewing SurfacesThe Sew method sequentially combines the actions of the Edit/ Point/ Equivalence method to equivalence surface vertices and the Edit/ Surface/Edge Match method to merge edges. The composite action is a "sewing" of the surfaces. Vertices and edges are both equivalenced according to the restrictions of the previously mentioned methods; however, since the operation is sequential, vertices will already be equivalenced before doing the edge merging.


Surface Sew Method Example

Edits surfaces 1 and 2 by closing the gap between edges which share common vertices.


572

Subtracting SurfacesThe Subtract method .


Trimming Surfaces to an EdgeThis form is used to trim a Surface with one of its edges and optionally delete the surface with the smallest surface area after the trim.


574

Tip: More Help:


Trim Surface To Edge Example

Trim the sliver from surface 5 by selecting the surface edge surface 5.4.


Adding a Fillet to a SurfaceThis form facilitates the creation of a fillet edge between two existing edges sharing a given vertex. This operation, when successful will replace the input vertex with a new edge.


576

Adding a Hole to Surfaces

Adding a Hole to Surfaces with the Center Point Option

The Add Hole method using the Center Point option adds a circular hole to a Surface. The circular hole is defined in the tangent plane of the supplied, manifolded center point.


Tip: More Help:


Adding a Hole to a Surface with the Center Point Option Example

This will add nine circular holes to surface 1 using points 52:60. Warning messages will be generated for the other points due to interference of holes at these points with surface edges.


578

Adding a Hole to Surfaces with the Project Vector Option

The Add Hole method using the Projection Vector option adds a circular hole to a Surface. The circular hole is defined in the plane of the supplied vector and vector-projected onto the surface.


Tip: More Help:


Adding a Hole to a Surface with the Project Vector Option codeindent10

This will add two holes to surface 6 using points 78 and 82 and the projection vector defined by the x axis of Coordinate Frame 0.


580

Adding a Hole to Surfaces with the Inner Loop Option

The Add Hole method using the Inner Loop option adds a hole to a Surface. The hole is defined by the supplied closed, chained curves which will define inner loops for the creation of a Trimmed Surface.


Tip: More Help:


Adding a Hole to a Surface with the Inner Loop Option Example

This will add 5 new holes to surface 6 using curves 14, 15, 16, 29, and 30.


582

Removing a Hole from Trimmed SurfacesThe Remove Hole method removes a hole from a Trimmed Surface. The hole to remove can be any edge-curves which are inner loops of a Trimmed Surface.


Tip: More Help:


Removing a Hole from a Trimmed Surface Example

This will remove all the small inner loops from surface 4.


584

Adding a Vertex to SurfacesThe Add Vertex method adds a vertex to a surface. The point used to create a vertex can be any point which is on the edge of the selected surface. If a hardpoint is converted to a surface vertex in the process of adding a vertex to a surface, then this point(vertex) cannot be reassociated to the surface as a hardpoint.


Tip: More Help:


Adding a Vertex to a Surface Example

This will add a vertex to surface 2 using point 3. The result is surface 2 becomes a trimmed surface with five vertices.


586

Removing a Vertex from Trimmed SurfacesThe Remove Vertex method removes a vertex from a Trimmed Surface. The vertex to remove can be any vertex of a Trimmed Surface with the exception that one vertex per loop must remain.


Tip: More Help:


Removing a Vertex from a Trimmed Surface Example

This will remove vertex 3.4.2 from trimmed surface 3. The result is a parametric bicubic surface.


588

589Chapter 6: Edit ActionsEditing Solids

Editing Solids

Breaking Solids

Breaking Solids with the Point Option

The Break method with the Point option breaks an existing solid into two or four smaller solids at a point location. The point location can be on or within the solid.

More Help:


Geometry Modeling - Reference Manual Part 2Editing Solids

590


• Topology

Solid Break Method with the Point Option Example

Breaks Solid 1 into eight solids by referencing Point 9. Notice that Delete Original Surfaces is pressed and Solid 1 is deleted.



This example is similar to the previous example, except that the break point is on a face instead of inside of Solid 1, and four solids are created instead of eight.


592


This example is similar to the previous example, except that the break point is on an edge instead of on a face of Solid 1, and two solids are created instead of four.


Breaking Solids with the Parametric Option

The Break method with the Parametric option creates two, four or eight solids from an existing solid. The break location is defined at the solid’s parametric , , and coordinate locations where has a

range of , has a range of and has a range of .

1 2 3 1

0 1 1 2 0 2 1 3 0 3 1


594


Tip: More Help:


• Topology

• Connectivity


Solid Break Method with the Parametric Option Example

Breaks Solid 1 into eight smaller solids at , , and . Notice that Delete Original

Surfaces is pressed and Surface 1 is deleted and that the parametric direction is displayed.

1 0.5= 2 0.5= 3 0.5=


596


This example is similar to the previous example, except instead of , and Surface 1 is

broken into four solids instead of eight.

1 0= 1 0.5=



This example is similar to the first example, except and instead of and ,

and Surface 1 is broken into two solids instead of eight.

1 0= 2 0= 1 0.5= 2 0.5=


598

Breaking Solids with the Curve Option

The Break method with the Curve option breaks an existing solid into two solids at a curve break location. The curve location must completely lie on and bisect a face of the solid.


Tip: More Help:



• Topology

Solid Break Method with the Curve Option Example

Breaks Solids 2 and 3 into two solids each at Curve 1. Notice that Delete Original Solids is pressed and Solid 1 is deleted.


600

Breaking Solids with the Plane Option

The method breaks a solid with a plane. The solid will be broken along its intersection with the plane.


Tip: More Help:



• Topology


602

Breaking a Solid with the Plane Option Example

Creates Solids 2 and 3 by breaking Solid 1 along its intersection with Plane 1. Notice that Delete Original Solids is pressed and Solid 1 is deleted.

Breaking Solids with the Surface Option

The Break method with the Surface option breaks an existing solid into two smaller solids at a surface break location. The surface break location must completely pass through the solid.


Tip: More Help:



• Topology

Solid Break Method with the Surface Option Example

Breaks Solid 1 into two solids at Surface 1. Notice that Delete Original Solids is pressed and Solid 1 is deleted.


604

Solid Break Method with the Surface Option Between Two Surfaces Example

This example is the same as the previous example, except that the solid is defined by Surfaces 2 and 3 by using the Solid select menu icon listed below.


Blending SolidsThe Blend method creates a set of parametric tri-cubic solids from an existing set of two or more solids, such that the first derivative continuity is maintained across the surface boundaries between adjacent solids. The existing solids can have any parametrization, but they must share common faces.


606

Tip: More Help:



• Topology


Solid Blend Method Example

Creates Solids 4, 5 and 6 by blending Solids 1, 2 and 3. Notice that Delete Original Solids is pressed and Solids 1, 2 and 3 are deleted.


Solid Blend Method Example

This example is similar to the previous example, except that weighting factors, 1e6 and 1e-6, are used so that Solids 1 and 3 dominate the slope.


608

Disassembling B-rep SolidsThe Disassemble method operates on one or more boundary represented (B-rep) solids and breaks them into the original surfaces that composed each B-rep solid. A B-rep solid can be created by the Geometry Application’s Create/Solid/B-rep form.


Tip: More Help:



610

Disassemble a B-rep Solid Example

Disassemble solid 1 into its constituent surfaces and convert all possible surfaces into Simply Trimmed surfaces (green). If “Conver to Simply Trimmed” toggle was OFF, the resulting surfaces would maintain their original type; (magenta).


Refitting Solids

Refitting Solids with the To TriCubicNet Option

This form is used to refit a solid to alternative mathematical solid representations. The form provides three Options; To TriCubicNet, To TriParametric, and To Parasolid.


612

Tip: More Help:


• Solids


• Creating a Boundary Representation (B-rep) Solid


Refitting Solids with the To TriParametric Option


Tip: More Help:


• Solids


614



Refitting Solids with the To Parasolid Option



Tip: More Help:


• Solids




616

Reversing SolidsThe Reverse method redefines the connectivity of an existing set of solids by exchanging the positive

and directions of the solids. Then, to maintain a positive parametric frame, Patran translates the

parametric origin up the original axis and then reverses the direction. You can plot the and

directions for the solids by pressing the Show Parametric Direction toggle on the Geometric Attributes

form found under the menu Display/Geometry.

Solid Reverse Method Example

Reverses the parametric directions for Solid 1 (only the top half of Solid 1 is shown). Notice that the parametric origin is relocated.

1

2

3 3 1 2

3


Solid Boolean Operation AddThis form is used to perform a Solid boolean of “Add”.


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Tip: More Help:


Solid Boolean Operation Add Example

Add Solids 2 and 3 to Solid 1.


Solid Boolean Operation SubtractThis form is used to perform a Solid boolean operation of “Subtract”.


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Tip: More Help:


Solid Boolean Operation Subtract Example

Subtract solids 2 and 3 from solid 1.


Solid Boolean Operation IntersectThis form is used to perform a Solid boolean operation of “Intersect”.


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Tip: More Help:


Solid Boolean Operation Intersect Example

Intersect solids 2 and 3 with solid


Creating Solid Edge Blends

Creating Constant Radius Edge Blends from Solid Edges

This form is used to create a constant radius edge blend on an edge(s) of a solid.


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Tip: More Help:


Creating Constant Radius Edge Blend from Solid Edges Example

Create an Edge Blend of Radius 0.25 on Solid 7 edges Solid 7.1.5 7.3.6 7.11.1 and 7.3.1.


Creating Chamfer Edge Blend from Solid Edges

This form is used to create a constant angle chamfer on an edge(s) of a solid.


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Tip: More Help:


Creating Chamfer Edge Blend from Solid Edges Example

Create Chamfers with offset of 0.02 and angle of 45 degrees on Solid 1 edges Solid 1.1.3 1.1.12 1.1.6 1.1.4 1.2.4 and 1.4.4.


Imprinting Solid on SolidThis form is used to imprint solid bodies on solid bodies.


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Tip: More Help:


Imprint Solid on Solid Example

Imprint Solid Cylinders 2 and 3 onto the faces of Solid Block 1. The Cylinders have been deleted to show the results of the imprint.


Solid Shell OperationThis form is used to create a void in a solid by shelling the selected faces.


630

Tip: More Help:


Solid Shell Operation Example

Shell solids 1t4 with a wall thickness=0.25 using faces solid 4.1 4.2 3.6 2.1 2.4 2.5 1.4 and 1.2.

Geometry Modeling - Reference Manual Part 2Editing Features

632

Editing Features

Suppressing a FeatureThe Edit,Feature,Suppress method displays the list of CAD features associated with the geometry that can be suppressed from the geometric model.

633Chapter 6: Edit ActionsEditing Features

Unsuppressing a FeatureThe Edit,Feature,Unsuppress method displays the list of CAD features associated with the geometry that can be unsuppressed from the geometric model.


634

Editing Feature ParametersThe Edit,Feature,Parameters method displays the list of CAD features associated with the geometry whose parameters can be edited to be used to regenerate the geometric model based on the new parameter values.

635Chapter 6: Edit ActionsEditing Features

Feature Parameter DefinitionThe Feature Parameter Definition form allows the parameters of a CAD feature to be displayed and modified for regeneration of a CAD model.


636

Chapter 7: Show ActionsGeometry Modeling - Reference Manual Part 2

7 Show Actions

Overview of the Geometry Show Action Methods 638

Showing Points 640

Showing Point Distance 642

Showing Surfaces 667

Showing Surface Normals 63

Showing Solids 675

Showing Coordinate Frames 677

Showing Planes 679

Showing Vectors 684

Geometry Modeling - Reference Manual Part 2Overview of the Geometry Show Action Methods

638

Overview of the Geometry Show Action MethodsFigure 7-1


Point • Location • Shows the coordinate value locations for a list of specified points or vertices. You may enter a reference coordinate system ID to express the coordinate values within.

• Distance • Shows the distance and the x, y and z offsets between one or more pairs of points and/or vertices.

• Node • Lists the IDs of the nodes that are located on a specified point or vertex that is within the Global Model Tolerance value.

Curve • Attributes • Lists the geometric type, length, and starting and ending points for a list of specified curves or edges.

• Arc • Shows the total number of Arcs in the model, total number of Arcs in the current group and the geometric modeling tolerance.

• Angle • Shows the angle between two curves for a list of specified curves or edges.

• Length Range • Shows the Start and End Point, Length, and Type for a list of specified curves or edges which are in the Minimum and Maximum Curve Length Range specified.

• Node • Lists the IDs of the nodes that are located on a specified curve or edge that is within the Global Model Tolerance value.

Surface • Attributes • Lists the number of vertices and edges associated with each specified surface or solid face, as well as the area and geometric type.

• Area Range • Shows the Vertices, Edges, Area, and Type for a list of specified surfaces or faces which are in the Minimum and Maximum Surface Area Range specified.

• Node • Lists the IDs of the nodes that are located on a specified surface or solid face that is within the Global Model Tolerance value.

Solid • Attributes • Lists the number of vertices, surfaces (or faces) associated with each specified solid, as well as the solid’s volume and geometric type.

Coord • Attributes • Shows the ID, the xyz coordinate location of the origin and the type for each specified coordinate frame.

Plane • Attributes

Vector • Attributes

639Chapter 7: Show ActionsOverview of the Geometry Show Action Methods

The Show Action Information FormWhen a Show action is executed, Patran will display a spreadsheet form at the bottom of the screen. This form displays information on the geometric entities that were specified on the Show action form.

Cells on the form that have a dot (.), means there is additional information associated with that cell. If a cell with the dot is pressed with the cursor, associated information is displayed in the textbox at the bottom of the form.

Tip: More Help:

• Show Point Distance Information Spreadsheet

• Show Point/Curve Distance Information Spreadsheet

• Show Point/Surface Distance Information Spreadsheet

• Show Curve Angle Information Spreadsheet

Geometry Modeling - Reference Manual Part 2Showing Points

640

Showing Points

Showing Point LocationsSetting Object to Point and Info to Location will show for a list of specified point locations, the coordinate value locations that are expressed within a specified reference coordinate frame. Also shown is the element property set assigned to the points. Point locations can be points, vertices, nodes or other point locations provided on the Point select menu.

641Chapter 7: Show ActionsShowing Points

Tip: More Help:


• Topology

• Global Model Tolerance & Geometry


• The Show Action Information Form

Geometry Modeling - Reference Manual Part 2Showing Point Distance

642

Showing Point Distance

Showing Point Distance with the Point Option

Show the distance between two points. A multi-page spreadsheet is used to display the distance, direction cosine and point location data for each point pair.

Tip: More Help:

643Chapter 7: Show ActionsShowing Point Distance


• Topology



Show Point Distance Information Spreadsheet


644

Cell Callback Actions

Showing Point Distance with the Curve Option

Show the distance between point/curve pairs. A multi-page spreadsheet is used to display the distance, direction cosine and minimum point location data for each point/curve pair.

From Point ID Highlights the point using the secondary highlight color; displays general information about the point (type, location, etc.) in the textbox.

To Point ID Highlights the point using the secondary highlight color; displays general information about the point (type, location, etc.) in the textbox.

Reference CID Highlights both points using the secondary highlight color; displays general information about the reference frame (type, origin, etc.) in the textbox.

Other columns Highlights both points using the secondary highlight color; displays the long (un-abbreviated) form of the data in the textbox.


Tip: More Help:


• Topology




646

Show Point/Curve Distance Information Spreadsheet



Showing Point Distance with the Surface Option

Show the distance between point/surface pairs. A multi-page spreadsheet is used to display the distance, direction cosine and minimum point location data for each point/surface pair.

From Point ID Highlights the point using the secondary highlight color; displays general information about the point (type, location, etc.) in the textbox.

From Curve ID Highlights the curve using the secondary highlight color; displays general information about the curve (type, etc.) in the textbox.

Reference CID Highlights both entities using the secondary highlight color; displays general information about the reference frame (type, origin, etc.) in the textbox.

Other Columns Highlights both entities using the secondary highlight color; displays the long (un-abbreviated) form of the data in the textbox; and displays a marker on the curve where the minimum distance occurs.


648

Tip: More Help:


• Topology




Show Point/Surface Distance Information Spreadsheet


650


Showing Point Distance with the Plane Option

Show the distance between point/Plane pairs. A multi-page spreadsheet is used to display the distance, direction cosine and minimum point location data for each point/plane pair.

To Point ID Highlights the point using the secondary Highlight color; displays general information about the point (type, location, etc.) in the textbox.

From Surface ID Highlights the surface using the secondary Highlight color; displays general information about the surface (type, etc.) in the textbox.

Reference CID Highlights both entities in the secondary Highlight color; displays general information about the reference frame (type, origin, etc.) in the textbox.

Other columns Highlights both entities in the secondary highlight color; displays the long (un-abbreviated) form of the data in the textbox; and displays a marker on the surface where the minimum distance occurs.


Tip: More Help:


• Topology




652

Show Point/Curve Vector Information Spreadsheet



Showing Point Distance with the Vector Option

Show the distance between point/vector pairs. A multi-page spreadsheet is used to display the distance, direction cosine and minimum point location data for each point/vector pair.


From Vector ID Highlights the plane using the secondary Highlight color; displays general information about the vector (type, etc.) in the textbox.


Other columns Highlights both entities in the secondary highlight color; displays the long (unabbreviated) form of the data in the textbox; and displays a marker on the surface where the minimum distance occurs.


654

Tip: More Help:


• Topology




Show Point/Curve Distance Information Spreadsheet


656


Showing the Nodes on a PointSetting Object to Point and Info to Node will show the IDs of the nodes that lie on at specified point locations that are within the Global Model Tolerance. Point locations can be points, vertices, nodes or other point locations provided on the Point select menu.


From Plane ID Highlights the plane using the secondary Highlight color; displays general information about the plane (type, etc.) in the textbox.


Other columns Highlights both entities in the secondary highlight color; displays the long (unabbreviated) form of the data in the textbox; and displays a marker on the surface where the minimum distance occurs.


Tip: More Help:


• Topology



Geometry Modeling - Reference Manual Part 2Showing Curves

658

Showing Curves

Showing Curve AttributesSetting Object to Curve and Info to Attributes will show the geometric type, length, the starting and ending points, and material and element properties for a list of specified curves or edges.

Tip: More Help:

659Chapter 7: Show ActionsShowing Curves

• Topology


• Types of Geometry in Patran


Showing Curve ArcSetting Object to Curve and Info to Arc will show the total number of Arcs in the model, total number of Arcs in the current group and the geometric modeling tolerance.


660

Tip: More Help:

• Topology





Showing Curve AngleSetting Object to Curve and Info to Angle will show the angle between pairs of curves. The point on each curve where the angle is calculated from is shown via a primary graphics marker in the graphics marker color. This is useful if the two curves do not intersect.

Tip: More Help:

• Topology


662



Show Curve Angle Information Spreadsheet



Showing Curve Length RangeSetting Object to Curve and Info to Length Range will show the Start and End Point, Length, and Type for a list of specified curves or edges which are in the Minimum and Maximum Curve Length Range specified.

First Curve ID Highlights the curve using the secondary highlight color; displays general information about the point (type, location, etc.) in the textbox.

Second Curve ID Highlights the curve using the secondary highlight color; displays general information about the curve (type, etc.) in the textbox.

Other Columns Highlights both curves in the secondary highlight color; displays the long (un-abbreviated) form of the data in the textbox; and displays a marker on each curve at the respective locations where the minimum distance occurs.


664

Tip: More Help:

• Topology





Showing the Nodes on a CurveSetting the Object to Curve and Info to Node will show the IDs of the nodes that lie on the specified curves or edges that are within the Global Model Tolerance.

Tip: More Help:

• Topology



666

• Types of Geometry in Patran (p. 19)


667Chapter 7: Show ActionsShowing Surfaces

Showing Surfaces

Showing Surface AttributesSetting the Object to Surface and Info to Attributes will list the number of vertices and edges associated with each specified surface or solid face, as well as the its area, geometry type and material and element properties .

Geometry Modeling - Reference Manual Part 2Showing Surfaces

668

Tip: More Help:


• Topology





Showing Surface Area RangeSetting Object to Surface and Info to Area Range will show the Vertices, Edges, Area, and Type for a list of specified surfaces or faces which are in the Minimum and Maximum Surface Area Range specified.

Tip: More Help:


• Topology


670

• Global Model Tolerance & Geometry (p. 18)

• Types of Geometry in Patran (p. 19)


Showing the Nodes on a SurfaceSetting the Object to Surface and Info to Node will show the IDs of the nodes that lie on the specified surfaces or solid faces that are within the Global Model Tolerance.


Tip: More Help:

• Topology





672

Showing Surface NormalsSetting the Object to Surface and Info to Normals enables the user to display surface normals of varying densities on the surface.


674

Tip: More Help:

• Topology




675Chapter 7: Show ActionsShowing Solids

Showing Solids

Showing Solid AttributesSetting the Object to Solid and Info to Attributes will list the number of vertices and faces associated with each specified solid, as well as the volume, geometry type and material and element properties .

Tip: More Help:


Geometry Modeling - Reference Manual Part 2Showing Solids

676

• Solids


677Chapter 7: Show ActionsShowing Coordinate Frames

Showing Coordinate Frames

Showing Coordinate Frame AttributesSetting the Object to Coord and Info to Attributes will list the ID, the coordinate value location of the coordinate frame’s origin and the coordinate frame type for each specified coordinate frame.

Tip: More Help:


Geometry Modeling - Reference Manual Part 2Showing Coordinate Frames

678

• Coordinate Frame Definitions, 60

• The Show Action Information Form, 639

679Chapter 7: Show ActionsShowing Planes

Showing Planes

Showing Plane AttributesSetting Object to Plane and Info to Attributes will show for a list of specified plane, displaying the plane origins and the plane normal that are expressed within a specified reference coordinate frame.

Tip: More Help:

• Showing Point Locations

Geometry Modeling - Reference Manual Part 2Showing Planes

680

Showing Plane AngleSetting Object to Plane and Info to Angle will show the angle between pairs of planes.


Show Plane Angle/Distance Information Spreadsheet

Geometry Modeling - Reference Manual Part 2Showing Planes

682

Showing Plane DistanceSetting Object to Plane and Info to Distance will show the distance between pairs of planes.

Geometry Modeling - Reference Manual Part 2Showing Vectors

684

Showing Vectors

Showing Vector AttributesSetting Object to Vector and Info to Attributes will show a list for a specified vector displaying the vector origins and the vector directions that are expressed within a specified reference coordinate frame.

Tip: More Help:

• Showing Point Locations

Chapter 8: Transform ActionsGeometry Modeling - Reference Manual Part 2

8 Transform Actions

Overview of the Transform Methods 686

Transforming Points, Curves, Surfaces, Solids, Planes and Vectors 689

Transforming Coordinate Frames 777

Geometry Modeling - Reference Manual Part 2Overview of the Transform Methods

686

Overview of the Transform MethodsObject Method Description

Point • Translate • Create points by successively offsetting them through a translation vector from an existing set of points, nodes or vertices.

• Rotate • Create points by performing a rigid body rotation about a defined axis from an existing set of points, nodes or vertices.

• Scale • Create points by scaling an existing set of points, nodes or vertices.

• Mirror • Create points by a defined mirror plane of an existing set of points, nodes or vertices.

• MCoord • Creates points by translating and rotating them from an existing set of points, nodes, or vertices by referencing coordinate frames.

• Pivot • Creates points from existing points, nodes or vertices by using a planar rotation defined by three point locations.

• Position • Creates points by translating and rotating existing points, nodes or vertices, using a transformation defined by three original and three destination point locations.

• Vsum • Creates points by performing a vector sum of the coordinate locations of two sets of existing points, nodes or vertices.

• MScale • Creates points by simultaneously moving, scaling, rotating and/or warping an existing set of points, nodes or vertices.

Curve • Translate • Create curves by successively offsetting them through a translation vector from an existing set of curves or edges.

• Rotate • Create curves by performing a rigid body rotation about a defined axis from an existing set of curves or edges.

• Scale • Create curves by scaling an existing set of curves or edges.

• Mirror • Create curves by a defined mirror plane of an existing set of curves or edges.

• MCoord • Creates curves by translating and rotating them from an existing set of curves or edges by referencing coordinate frames.

• Pivot • Creates curves from existing curves or edges by using a planar rotation defined by three point locations.

• Position • Creates curves by translating and rotating existing curves or edges, using a transformation defined by three original and three destination point locations.

• Vsum • Creates curves by performing a vector sum of the coordinate locations of two sets of existing curves or edges.

• MScale • Creates curves by simultaneously moving, scaling, rotating and/or warping an existing set of curves or edges.

687Chapter 8: Transform ActionsOverview of the Transform Methods

Surface • Translate • Create surfaces by successively offsetting them through a translation vector from an existing set of surfaces or solid faces.

• Rotate • Create surfaces by performing a rigid body rotation about a defined axis from an existing set of surfaces or solid faces.

• Scale • Create a set of curves by scaling an existing set of curves or edges.

• Mirror • Create surfaces by a defined mirror plane of an existing set of surfaces or solid faces.

• MCoord • Creates surfaces by translating and rotating them from an existing set of surfaces or solid faces by referencing coordinate frames.

• Pivot • Creates surfaces from existing surfaces or solid faces by using a planar rotation defined by three point locations.

• Position • Creates surfaces by translating and rotating existing surfaces or solid faces, using a transformation defined by three original and three destination point locations.

• Vsum • Creates surfaces by performing a vector sum of the coordinate locations of two sets of existing surfaces or solid faces.

• MScale • Creates surfaces by simultaneously moving, scaling, rotating and/or warping an existing set of surfaces or solid faces.

Solid • Translate • Create solids by successively offsetting them through a translation vector from an existing set of solids.

• Rotate • Create solids by performing a rigid body rotation about a defined axis from an existing set of solids.

• Scale • Create solids by scaling an existing set of solids.

• Mirror • Create solids by a defined mirror plane of an existing set of solids.

• MCoord • Creates solids by translating and rotating them from an existing set of solids by referencing coordinate frames.

• Pivot • Creates solids from existing solids by using a planar rotation defined by three point locations.

• Position • Creates solids by translating and rotating existing solids, using a transformation defined by three original and three destination point locations.

• Vsum • Creates solids by performing a vector sum of the coordinate locations of two sets of existing solids.

• MScale • Creates solids by simultaneously moving, scaling, rotating and/or warping an existing set of solids.


Geometry Modeling - Reference Manual Part 2Overview of the Transform Methods

688

Coord • Translate • Create rectangular, cylindrical or spherical coordinate frames by successively offsetting them through a translation vector from an existing set of coordinate frames.

• Rotate • Create rectangular, cylindrical or spherical coordinate frames by performing a rigid body rotation about a defined axis from an existing set of coordinate frames.

Plane • Translate • Create solids by successively offsetting them through a translation vector from an existing set of solids.






Vector • Translate • Create solids by successively offsetting them through a translation vector from an existing set of solids.






• Scale • Create solids by scaling an existing set of solids.


689Chapter 8: Transform ActionsTransforming Points, Curves, Surfaces, Solids, Planes and Vectors

Transforming Points, Curves, Surfaces, Solids, Planes and Vectors

Translating Points, Curves, Surfaces, Solids, Planes and VectorsThe Translate method creates a set of points, curves, surfaces, solids planes or vectors which are successively offset from each other by a defined Translation Vector <dx dy dz>. Points can be translated from points, vertices or nodes. Curves can be translated from curves or edges. Surfaces can be translated from surfaces or solid faces. Solids are translated from solids.

Geometry Modeling - Reference Manual Part 2Transforming Points, Curves, Surfaces, Solids, Planes and Vectors

690


Tip: More Help:



• Translating or Scaling Geometry Using Curvilinear Coordinate Frames

Translating Points Radially

Creates Points 8 through 14 by translating Points 1 through 7, three units radially outward within the cylindrical coordinate frame, Coord 100. Notice that Curvilinear in Refer. CF is pressed.


692

Translating Points

This example is the same as the previous example, except Cartesian in Refer. CF is pressed instead of Curvilinear in Refer. CF.


Translating Curves

Creates Curves 2 through 6 by translating Curves 1 three times - two units in the X direction and one unit in the Y direction within the global rectangular coordinate frame, Coord 0.


694

Translating Curves Radially

Translates Curve 1 three times and radially one unit outward within the cylindrical coordinate frame, Coord 100. Notice that Curvilinear in Refer. CF is pressed.


Translating Edges

Creates Curve 2 by translating the outside edge of Surface 1, two units radially outward within cylindrical coordinate frame, Coord 100.


696

Translating Surfaces

Creates Surfaces 2 and 3 by translating Surface 1 two times - one unit in the X direction and two units in the Y direction within the rectangular coordinate frame, Coord 10.


Translating Surfaces Radially

Creates Surfaces 2 through 4 by translating Surface 1 three times and one unit radially outward within the cylindrical coordinate frame, Coord 100.


698

Translating Solid Faces

Creates Surfaces 1 through 4 by translating the top faces of Solids 1 through 4, 0.5 units radially outward within the spherical coordinate frame, Coord 20. Notice that Curvilinear in Refer. CF is pressed.


Translating Solids

Translates Solids 1 through 4, 1.5 units in the X direction and 1.5 units in the Y direction, within the global rectangular coordinate frame, Coord 0. Notice that Delete Original Solids is pressed and Solids 1:4 are deleted.


700

Translating Solids

Creates Solid 2 by translating Solid 1, 90 degrees within the cylindrical coordinate frame, Coord 1. Notice that Curvilinear in Refer. CF is pressed.


Translating Planes

Translates Plane 1 2 units in the Z direction with the global rectangular coordinate frame, Coord 0. Note that Delete Original Plane is not pressed and Plane 1 is kept.


702

Translating Vectors

Translates Vector 1 2 units in the X direction with the global rectangular coordinate frame, Coord 0. Notice that Delete Original Vector is not pressed and Vector 1 is kept.


Rotating Points, Curves, Surfaces, Solids, Planes and VectorsCreates a set of points, curves, surfaces, solids, planes or vectors by a rigid body rotation about a defined axis from an existing set of entities. Points can be rotated from other points, vertices or nodes. Curves can be rotated from other curves or edges. Surfaces can be rotated from other surfaces or solid faces. Solids are rotated from other solids.


704


Tip: More Help:



Rotating Points and Nodes

Creates Points 7 through 14 from Point 1 and Node 10 by rotating them six times, 30 degrees about the global rectangular coordinate frame’s Z axis, Coord 0.3, with an offset angle of 60 degrees. (Coord 0.3 can be cursor defined by using the Axis select menu icon listed below and cursor selecting Coord 0.)


706

Rotating Curves

Creates Curves 2 through 7 by rotating Curve 1 six times, 30 degrees about the axis defined by {[0 0 0][0 0 1]}. Notice that the axis definition is equivalent to Coord 0.3 from the previous example.


Rotating From An Edge

This example is the same as the previous example, except that Curves 1 through 6 are rotated from an edge of Surface 1.


708

Rotating Surfaces

Creates Surfaces 4 through 18 by rotating from Surfaces 1, 2 and 3, five times, 30 degrees each about the axis defined by Points 4 and 1. The axis is defined by cursor selecting the points using the Axis select menu icon listed below.


Rotating From Solid Faces

This example is the same as the previous example, except that Surfaces 1 through 16 are rotated from the outside faces of Solid 1.


710

Rotating Solids

Creates Solids 2 through 4 by rotating from Solid 1, three times, 90 degrees each about the global Z axis, Coord 0.3. Coord 0.3 is cursor defined by using the Axis select menu icon listed below.


Rotating Planes

Rotates Plane 1 90 degrees around the Y Axis in the global rectangular coordinate frame, Coord 0. Notice that Delete Original Plane is not pressed and Plane 1 is kept.


712

Rotating Vectors

Rotates Vector 1 90 degrees around the Z Axis in the global rectangular coordinate frame, Coord 0. Notice that Delete Original Vector is not pressed and Vector 1 is kept.


Scaling Points, Curves, Surfaces, Solids and VectorsThe Scale method creates a set of points, curves, surfaces, solids or vectors by scaling an existing set of entities. Points can be scaled from other points, vertices or nodes. Curves can be scaled from other curves or edges. Surfaces can be scaled from other surfaces or solid faces. Solids are scaled from other solids.


714


Tip: More Help:



• Translating or Scaling Geometry Using Curvilinear Coordinate Frames

Scaling Points and Nodes

Creates Points 6 through 9 by scaling them from Points 1, 2, 5 and Node 100 two times along the global X and Y axes, with Point 4 as the origin of scaling.


716

Scaling Points Radially

Creates Points 25 through 44 by scaling them from the points on the outside edge of Surfaces 1 through 4, two times radially within the cylindrical coordinate frame, Coord 100. Notice that Curvilinear in Refer. CF and Delete Original Points are pressed.


Scaling Curves

Creates Curve 2 by scaling them from Curve 1, 1.5 times along the X axis of rectangular coordinate frame, Coord 20. Notice that Delete Original Curves is pressed and Curve 1 is deleted.


718

Scaling From An Edge

Creates Curves 1 through 4 by scaling them from the outside edges of Surfaces 1 through 4, 1.5 times radially outward within the cylindrical coordinate frame, Coord 20. Notice that Curvilinear in Refer. CF is pressed.


Scaling Surfaces

Creates Surfaces 5 through 8 by scaling Surfaces 1 through 4 1.5 times along the radial axis of cylindrical coordinate frame, Coord 20. Notice that Cartesian in Refer. CF and Delete Original Surfaces are pressed.


720

Scaling Surfaces Radially

This example is the same as the previous example, except that Curvilinear in Refer. CF is selected instead of Cartesian in Refer. CF.


Scaling From Solid Faces

Creates Surface 1 by scaling it from the top face of Solid 1, 1.5 times in the X, Y and Z directions of the global rectangular coordinate frame, Coord 0.


722

Scaling From Solids

Creates Solids 5 through 8 by scaling them from Solids 1 through 4, two times in the X and Y directions of the global rectangular coordinate frame, Coord 0.


Scaling From Vectors

Scales Vector 1 with a scale factor of 2 in the X direction in the global rectangular coordinate frame, Coord 0. Notice that Delete Original Vector is not pressed and Vector 1 is kept.


724

Mirroring Points, Curves, Surfaces, Solids, Planes and VectorsCreates a set of points, curves, surfaces, solids, planes or vectors by a defined mirror plane of an existing set of entities. Points can be mirrored from other points, nodes or vertices. Curves can be mirrored from other curves or edges. Surfaces can be mirrored from other surfaces or solid faces. Solids are mirrored from other solids.


Tip: More Help:



Mirroring Points and Nodes

Creates Points 7 through 12 by mirroring them from Points 1 through 6 and Node 100, about the mirror plane whose normal is the global X axis, Coord 0.1. Coord 0.1 can be cursor defined by using the Axis select menu icon listed below.


726

Mirroring Curves

Creates Curves 3 and 4 by mirroring them from Curves 1 and 2 about the plane whose normal is the global Y axis, Coord 0.2, and with an offset of Y=-1.


Mirroring From Edges

Creates Curves 1 through 8 by mirroring them from the inner and outer edges of Surfaces 5 through 8 about the plane whose normal is rectangular coordinate frame 1’s Y axis, Coord 1.2.


728

Mirroring Surfaces

This example is similar to the previous example, except that Surfaces 1 through 4 are mirrored from Surfaces 5 through 8.


Mirroring Solids

Creates Solid 2 by mirroring Solid 1 about the plane whose normal is defined by {[0 0 0][1 0 0]}. Notice that the mirror plane normal definition is the same as entering the global X axis, Coord 0.1.


730

Mirroring Planes

Mirrors Plane 1 against the X-Y plane and with an offset of 1 unit in the Z direction in the global rectangular coordinate frame, Coord 0. Notice that Delete Original Plane is not pressed and Plane 1 is kept. Also, the Reverse Plane is not pressed and Plane 2 is not reversed.


Mirroring Vectors

Mirrors Vector 1 against the X-Y plane and with an offset of 1 unit in the Z direction in the global rectangular coordinate frame, Coord 0. Notice that Delete Original Vector is not pressed and Vector 1 is kept. Also, the Reverse Vector is not pressed and Vector 2 is not reversed.


732

Moving Points, Curves, Surfaces, Solids, Planes and Vectors by Coordinate Frame Reference (MCoord Method)Translates and rotates a new set of points, curves, surfaces, solids, planes or vectors from an existing set of entities by referencing coordinate frames. The new entities’ local position with respect to the To Coordinate Frame is the same as the local position of the original entities with respect to the From Coordinate Frame. Points can be moved from other points, nodes or vertices. Curves can be moved from other curves or edges. Surfaces can be moved from other surfaces or solid faces. Solids are moved from other solids.


Tip: More Help:



Moving Points and Nodes

Creates Points 7 through 12 from Points 1, 3, 4, 5, 6 and Node 100 by moving them from the global rectangular coordinate frame, Coord 0, to the rectangular coordinate frame, Coord 100.


734

Moving Curves

Creates Curves 7 through 12 by moving Curves 1 through 6 from cylindrical coordinate frame, Coord 200 to cylindrical coordinate frame, Coord 300.


Moving From Edges

This example is similar to the previous example, except that Curves 1 through 8 are moved from the outside edges of Surfaces 1 through 4, from Coord 200 to Coord 300.


736

Moving Surfaces

Creates Surfaces 5 through 8 by moving from Surfaces 1 through 4 from cylindrical coordinate frame, Coord 200, to cylindrical coordinate frame, Coord 300.


Moving Solids

Creates Solids 5 through 8 by moving Solids 1 through 4 from the global coordinate frame, Coord 0, to the rectangular coordinate frame, Coord 1.


738

Moving Planes

Moves Plane 1 from the rectangular coordinate frame, Coord 0, to the rectangular coordinate frame, Coord 1. Notice that Delete Original Plane is not pressed and Plane 1 is kept.


Moving Vectors

Moves Vector 1 from the rectangular coordinate frame, Coord 0, to the rectangular coordinate frame, Coord 1. Notice that Delete Original Vector is not pressed and Vector 1 is kept.


740

Pivoting Points, Curves, Surfaces, Solids, Planes and VectorsCreates points, curves, surfaces, solids, planes and vectors by using a planar rotation defined by a specified Pivot Point about which the entity will be rotated, and a Starting Point and Ending Point for the rotation. Points can be pivoted from other points, nodes or vertices. Curves can be pivoted from other curves or edges. Surfaces can be pivoted from other surfaces or solid faces. Solids are pivoted from other solids.


Tip: More Help:



742


Pivoting Points

Creates Point 4 from Point 3 by pivoting at the global origin, [0 0 0], from Node 100 to Point 2.


Pivoting Curves

Creates Curves 9 through 15 from Curves 1 through 6 by pivoting them at Point 12, from Point 14 to Point 13. (Curves 7 and 8 are for illustration and are not used for the pivot.)


744

Pivoting From Edges

Creates Curves 9 through 16 by pivoting from the outside edges of Surfaces 1 through 4, at Point 12, from Point 14 to Point 13. Curves 7 and 8 are for illustration and are not used for the pivot.


Pivoting Surfaces

This example is similar to the previous example, except that Surfaces 1 through 4 are pivoted to create Surfaces 5 through 8. Curves 7 and 8 are for illustration and are not used for the pivot.


746

Pivoting Solids

Creates Solid 2 by pivoting from Solid 1 at Point 1, from Point 2 to Point 3. Curves 1 and 2 are for illustration and are not used for the pivot.


Pivoting Planes

Pivots Plane 1 using the 3 pivoting points, Point 1 through 3. Notice that Delete Original Plane is not pressed and Plane 1 is kept.


748

Pivoting Vectors

Pivots Vector 1 using the 3 pivoting points, Point 1 through 3. Notice that Delete Original Vector is not pressed and Vector 1 is kept.


Positioning Points, Curves, Surfaces, Solids, Planes and VectorsCreates points, curves, surfaces, solids, planes and vectors by translating and rotating an existing set of entities using a transformation defined by three original point locations to three destination point locations.


750

The original points and destination points need not match exactly; however, if either the original point locations or the destination point locations lie in a straight line, the transformation cannot be performed. Points can be repositioned from other points, nodes or vertices. Curves can be repositioned from other curves or edges. Surfaces can be repositioned from other surfaces or solid faces. Solids are repositioned from other solids.


752

Tip: More Help:

• Select Menu (p. 33) in the MD Patran Reference Manual, Part 1: Basic Functions

• Coordinate Frame Definitions (p. 60)

Positioning Points

Creates Points 9 through 12 from Points 1through 4 by repositioning them based on the original and destination point locations listed on the form.


Positioning Curves

Creates Curves 25 through 32 by repositioning Curves 13 through 24 from Points 9, 13 and 12, to destination Points 2, 6 and 3. Notice that Delete Original Curves is pressed and Curves 13 through 24 are deleted.


754

Positioning From Edges

This example is similar to the previous example, except that the edges of Solid 1 are repositioned to the new location to create Curves 13 through 20.


Positioning Surfaces

Creates Surface 5 from Surface 4 by positioning it from Points 8, 9 and 11 to the destination Points 7, 2 and 3.


756

Positioning Solids

Creates Solid 3 by repositioning it from Solid 2, based on the original and destination points listed on the form. Notice that Delete Original Solids is pressed and Solid 2 is deleted.


Positioning Planes

Positions Plane 1 from where defined by the position Point 1 through 3, to where defined by the position Point 4 through 6. Notice that Delete Original Plane is not pressed and Plane 1 is kept.


758

Positioning Vectors

Positions Vector 1 from where defined by the position Point 1 through 3, to where defined by the position Point 4 through 6. Notice that Delete Original Vector is not pressed and Vector 1 is kept.


Vector Summing (VSum) Points, Curves, Surfaces and SolidsCreates points, curves, surfaces or solids by performing a vector sum of the coordinate locations of two sets of existing entities to form one set of new entities. Points can be created from the summation of other points, nodes or vertices. Curves can be created from the summation of other curves or edges. Surfaces can be created from the summation of other surfaces or solid faces. Solids are created from the summation of other solids.


760


Tip: More Help:



Vector Summing Points

Creates Points 7, 8 and 9 by summing the vectors drawn from the origin, [0 0 0], to Points 1 and 4, 2 and 5 and 3 and 6. The “After” picture below has the vectors drawn to Points 2 and 5 to show how Point 8 was created.


762

Vector Summing Points

This example is the same as the previous example, except that a Multiplication Factor 2 is increased from “1 1 1” to “2 2 2”.


Vector Summing Curves

Creates Curves 20 through 27 which are summed between Curves 12 through 19 and Curves 1 through 4. Notice that in order to create the spiral, Curve 1:4 must be entered twice in the Curve 2 List to match the eight curves listed in the Curve 1 List.


764

Vector Summing Curves

Creates Curve 3 by summing Curves 1 and 2. Notice that the multiplication factors of “.5 .5 .5” are entered for both Multiplication Factors 1 and 2 and Curve 3 becomes the “average” of Curves 1 and 2 in length and in curvature.


Vector Summing Surfaces

This example creates Surface 4 from vector summing the coordinate locations of Surfaces 1 and 3.


766

Vector Summing With Solid Faces

This example is similar to the previous example, except that Surface 4 is created by vector summing the coordinate locations of the outside face of Solid 1 and Surface 3.


Vector Summing Solids

Creates Solid 3 by vector summing the coordinate locations of Solids 1 and 2.


768

Moving and Scaling (MScale) Points, Curves, Surfaces and SolidsCreates a set of points, curves, surfaces and solids by simultaneously moving, scaling, rotating and/or warping an existing set of entities. Points can be moved and scaled from other points, nodes or vertices.


Curves can be moved and scaled from other curves or edges. Surfaces can be moved and scaled from other surfaces or solid faces. Solids are moved and scaled from other solids.


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Tip: More Help:



Translating and Mirroring Points

Creates Points 8 through 13 by simultaneously translating and mirroring Points 1 though 7, two units in the global X direction and mirroring about the global YZ plane.


772

Mirroring and Scaling Curves

Creates Curves 7 through 12 by simultaneously scaling and mirroring Curves 1 through 6. The curves are scaled two times in the global Y direction and they are mirrored about the global XZ plane.


Mirroring and Scaling Curves

This example is similar to the previous example, except that the curves are mirrored and scaled within the rectangular coordinate frame, Coord 100.


774

Translating and Rotating Surfaces

Creates Surfaces 5 through 8 from Surfaces 1 through 4 by translating them 10 units in the global Z direction and rotating them -120 degrees about the global X axis.


Translating, Mirroring and Scaling Solids

This example simultaneously translates, mirrors and scales Solids 5 through 8 from Solids 1 through 4, by translating them 1.57 units in the global X direction and 1.0 unit in the global Y direction; mirroring them about the global XZ plane; and scaling them .5 in the X direction and .5 in the Y direction.


776

777Chapter 8: Transform ActionsTransforming Coordinate Frames

Transforming Coordinate Frames

Translating Coordinate FramesCreates coordinate frames which are successively offset from each other by the Translation Vector <dx dy dz>, starting from an existing set of specified coordinate frames.

Tip: More Help:

Geometry Modeling - Reference Manual Part 2Transforming Coordinate Frames

778



Translating Coordinate Frames

Creates the rectangular coordinate frame, Coord 2, from coordinate frame, Coord 1, by translating it two units in the global X direction.


Translating Coordinate Frames

Creates the rectangular coordinate frame, Coord 2, from coordinate frame, Coord 1, by translating it through a translation vector defined by Points 1 and 2, using the Vector select menu icon listed below.


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Rotating Coordinate FramesCreates a set of coordinate frames which are formed from a specified set of existing coordinate frames by a rigid body rotation about a defined axis.


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Rotating Coordinate Frames

Creates the rectangular coordinate frame, Coord 2, from coordinate frame, Coord 1, by rotating it 45 degrees about the axis listed on the form.


Rotating Coordinate Frames

Creates the cylindrical coordinate frame, Coord 200, from cylindrical coordinate frame, Coord 100, by rotating it 90 degrees about Coord 100’s Z axis, Coord 100.3, using the Axis select menu icon listed below. Notice that Delete Original Coords is pressed and Coord 100 is deleted.


784

Chapter 9: Verify ActionsGeometry Modeling - Reference Manual Part 2

9 Verify Actions

Verify Actions 785

Geometry Modeling - Reference Manual Part 2Verify Action

786

Verify Action

Verifying Surface BoundariesThe Boundary method for surfaces will allow you to plot the free or non-manifold edges for a list of specified surfaces or solid faces. A free edge is any edge that is not shared by at least one other surface or solid face. A non-manifold edge is shared by more than two surfaces or solid faces. Non-manifold often indicates a geometry which is not manufacturable; it may be alright for surface models or on shared solid faces, but is illegal in a B-rep solid.This method is recommended for verifying cracks in the model, or more specifically in a surface set to be used in creating a B-rep solid.

787Chapter 9: Verify ActionsVerify Action


788

Verifying Surfaces for B-repsThe B-rep method for surfaces will allow you to plot the free or non-manifold edges for a list of specified surfaces or solid faces. A free edge is any edge that is not shared by at least one other surface or solid face. A non-manifold edge is shared by more than two surfaces or solid faces. Non-manifold often indicates a geometry which is not manufacturable; it may be alright for surface models or on shared solid faces, but is illegal in a B-rep solid.This method is recommended for verifying cracks in the model, or more specifically in a surface set to be used in creating a B-rep solid.


Update Graphics Subordinate Form

The Update Graphics subordinate form is displayed when the Update Graphics button is pressed on the Verify/Surface/Boundaries form. This subordinate form allows you to erase or plot in the current viewport, groups of congruent or incongruent surfaces.

This form is useful for checking for surface cracks, topologically incongruent surfaces, or non-manifold edges shared by more than two surfaces. MSC.Software Corporation suggests you use either the Edit/Surface/Edge Match form (see Matching Surface Edges) or the Create/Surface/Match form (see Matching Adjacent Surfaces) to correct any incongruent surfaces that have a gap between them.


790

Tip: More Help:


• Building a Congruent Model

• Group>Create (p. 271) in the Patran Reference Manual

Verify - Surface (Duplicates)Surfaces in the entire model are checked for being duplicate.


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Chapter 10: Associate ActionsGeometry Modeling - Reference Manual Part 2

10 Associate Actions

Overview of the Associate Action 794

Geometry Modeling - Reference Manual Part 2Overview of the Associate Action

794

Overview of the Associate ActionThe Associate action causes a geometric entity to become embedded on another geometric entity. Surfaces with associated geometry will not get trimmed (i.e., a four sided iso parametric patch will remain so even after associations are made to the patch).

Associations allow the mesher to create nodes on or along the associated geometry.

Loads or boundary conditions may be applied to associated geometries.

Mesh seeds can be placed on the associated geometry.

The nodes lying on the associated geometry have the associated geometry as topological associations (i.e., nodes that lie on a curve associated to a surface will have their topological associations to the curve rather than with the surface).

Associations are marked by filled blue triangles for points and filled yellow triangles for curves.

Table 10-1 Geometry Associate Action Objects and Descriptions


• Point Curve Associate point to a curve.

Surface Associate point to a surface.

• Curve Curve Associate curve to a curve.

Surface Associate curve to a surface.

Important:The iso-mesher will not generate meshes that conform to hard geometries, if the hard geometries lie interior to the surface. The iso-mesher ignores the interior hard geometries to mesh the surface.

795Chapter 10: Associate ActionsOverview of the Associate Action

Associating Point Object

Figure 10-1


796

Figure 10-2

797Chapter 10: Associate ActionsOverview of the Associate Action

Associating Curve Object

Figure 10-3


798

Figure 10-4

Chapter 11: Disassociate ActionsGeometry Modeling - Reference Manual Part 2

11 Disassociate Actions

Overview of the Disassociate Action Methods 800

Geometry Modeling - Reference Manual Part 2Overview of the Disassociate Action Methods

800

Overview of the Disassociate Action MethodsThe disassociate action causes the association records to be deleted. All other information such as mesh seed and loads and boundary conditions will be preserved on the disassociated entity, if there are any.

The disassociate action causes the filled blue triangles and yellow triangles that mark the association of points and curves respectively, to be removed.

801Chapter 11: Disassociate ActionsOverview of the Disassociate Action Methods

Disassociating Points

Figure 11-1

Object Description

• Point • Remove all point associations.

• Curve • Remove all curve associations.

• Surface • Remove all surface associations.


802

Disassociating Curves

Disassociating Surfaces

803Chapter 11: Disassociate ActionsOverview of the Disassociate Action Methods

Figure 11-2


804

Chapter 12: The Renumber Action... Renumbering GeometryGeometry Modeling - Reference Manual Part 2

12 The Renumber Action... Renumbering Geometry

Renumber Forms 807

Geometry Modeling - Reference Manual Part 2Introduction

806

IntroductionMost often, ID numbers (IDs) for geometric entities are chosen and assigned automatically. The Renumber Action permits the IDs of points, curves, surfaces, solids, planes, or vectors to be changed. This capability is useful to:

• Offset the IDs of a specific list of entities.

• Renumber the IDs of all existing entities within a specified range.

• Compact the IDs of an entity type sequentially from 1 to N.

IDs must be positive integers. Duplicate IDs are not permitted in the List of New IDs, or in the selected Entity List (old IDs). A Starting ID or a List of New IDs may be entered in the input databox. If a geometric entity outside the list of entities being renumbered is using the new ID, the renumber process will print a warning message stating which ID is already in use and proceed to use the next highest avaliable ID since each entity must have a unique ID. The default is to renumber all the existing entities beginning with the minimum ID through the maximum ID consecutively starting with 1.

If only one ID is entered, it is assumed to be the starting ID. The entities will be renumbered consecutively beginning with the starting ID.

If more than one ID is entered and there are fewer IDs in the List of New IDs than there are valid entities in the selected Entity List, renumbering will use the IDs provided and when the list is exhausted, the next highest available ID will be used thereafter to complete the renumbering. The List of New IDs may contain a # signifying to use the maximum ID + 1 as the Starting ID. However, the list may have more IDs than needed.

The IDs in the selected Entity List may contain a #. The value of the maximum existing ID is automatically substituted for the #. There may be gaps of nonexisting entities in the list but there must be at least one valid entity ID in order for renumbering to take place.

A percent complete form shows the status of the renumber process. When renumbering is complete, a report appears in the command line indicating the number of entities renumbered and their new IDs. The renumber process may be halted at any time by pressing the Abort button and the old IDs will be restored.

807Chapter 12: The Renumber Action... Renumbering GeometryRenumber Forms

Renumber FormsWhen Renumber is the selected Action the following options are available.

Object Description

• Point • The point menu selection provides the capability to renumber or change the IDS of points.

• Curve • The curve menu selection provides the capability to renumber or change the IDs of curves.

• Surface • The surface menu selection provides the capability to renumber or change the IDs of surfaces.

• Solid • The solid menu selection provides the capability to renumber or change the IDs of solids.

• Plane • The plane menu selection provides the capability to renumber or change the IDs of planes.

• Vector • The vector menu selection provides the capability to renumber or change the IDs of vectors.

Geometry Modeling - Reference Manual Part 2Renumber Forms

808

Renumber Geometry

MSC.Fatigue Quick Start Guide

I n d e xGeometry Modeling - Reference Manual Part 2

Index

Index

Numerics3 point method

overview, 64

Aaccuracy, 2any geometry entity

delete action, 463arc center

point, 82arc3point method

curve, 130axis method

overview, 64

Bbi-parametric surface, 20blend method

curve, 482solid, 605surface, 536

body, 11break method

curve, 472, 476, 480example, 32solid, 589, 593, 598, 600, 602surface, 518, 522, 526, 530, 532

B-rep method, 41B-rep solid, 8, 20, 24, 41

exterior shell, 41shell, 24

building a B-rep solid, 41building a congruent model, 31

example, 32building a degenerate solid, 43building a degenerate surface, 42building optimal surfaces, 33

CCAD access modules, 47CAD user file, 2, 20, 46, 47capabilities, 2Cartesian in Refer. CF button, 67CATIA, 2, 47chain method

curve, 133chained curve, 21, 22conic method

curve, 135connectivity

curve, 16definition, 16modifying, 18solid, 17surface, 17

coordinate frameattributes

show action, 677create method overview, 64definitions, 60delete action, 466rotate method, 780translate method, 777

create action, 27overview, 72


810

curvearc3point method, 130blend method, 482break method, 472, 476, 480chain method, 133conic method, 135delete action, 464disasemble method, 485extend method, 488, 494, 497, 499extract method, 139, 143fillet method, 145fit method, 149intersect method, 151, 155manifold method, 161mcoord method, 732merge method, 502mirror method, 724mscale method, 768offset method constant, 171offset method variable, 173pivot method, 740point method, 120, 122, 125position method, 749refit method, 506reverse method, 508rotate method, 703scale method, 713translate method, 689trim method, 511, 514vsum method, 759XYZ method, 199

curve 4 point parametric positions subordinate form, 129

curve angleshow action, 661

curve arcshow action, 659

curve attributesshow action, 658

curve length rangeshow action, 663

curve method, 42curvilinear coordinate frame, 67

examples using translate and scale, 67scale method, 67translate method, 67

Curvilinear in Refer. CF button, 67cylindrical coordinate frame

definition, 61

DDassault Systemes, 2, 47Decompose method, 38decomposing trimmed surfaces, 38

example, 39default colors, 20, 21, 22, 24degenerate surfaces and solids, 42delete action

any geometry entity, 463coordinate frame, 466curve, 464overview, 462plane, 464point, 464solid, 464surface, 464vector, 464

DGA, 2, 47Direct Geometry Access, 2, 47disasemble method

curve, 485surface, 539

disassemble methodsolid, 608

display lines, 34, 41

Eedge, 11edge match method, 32

closing gaps, 15surface, 546, 549

edge method, 42edge refit method

surface, 566edit action, 27

overview, 468EDS/Unigraphics, 2, 47element connectivity, 35element properties, 2equivalence method

point, 470

811INDEX

euler methodoverview, 65

examplesarc3point curve, 131, 132ArcCenter point, 83blend

curve, 483, 484solid, 606, 607surface, 538

breakcurve, 473, 474, 475, 478, 479solid, 590, 591, 592, 595, 596, 597,

599, 603, 604surface, 519, 520, 521, 523, 527, 528,

529, 531, 534, 535chain curve, 134conic curve, 137, 138disassemble

curve, 487surface, 541

edge match surface, 548, 550equivalencene point, 470extend curve, 491, 492, 493, 496, 499, 501extend surface, 552, 554, 556, 558, 561,

563, 565extract

curve, 140, 141, 142, 144point, 85, 86point from surface, 88point from surface diagonal, 90point from surface parametric, 92

fillet curve, 147, 148fit curve, 150interpolate point, 95, 96, 99intersect

curve, 152, 153, 154, 156, 157point at edge, 101point with curve and plane, 105point with two curves, 102, 103, 104point with vector and curve, 106, 107point with vector and plane, 109point with vector and surface, 108

manifold curve, 163mcoord

curve, 734, 735plane, 738point, 733solid, 737surface, 736vector, 739

merge curve, 504, 505, 510, 513, 516mirror

curve, 726, 727plane, 730point, 725solid, 729, 731surface, 728

mscalecurve, 772, 773


812

point, 771solid, 775surface, 774

offset curve, 172, 175offset point, 111offset surface, 272pierce point, 113, 114pivot

curve, 743, 744plane, 747point, 742solid, 746surface, 745vector, 748

point curve, 121, 123, 124, 127, 128position

curve, 753, 754point, 752solid, 756, 757, 758surface, 755

project point, 117, 118, 119reverse

curve, 510solid, 616surface, 569

rotatecoordinate frame, 782, 783curve, 706, 707plane, 711point, 705solid, 710surface, 708, 709vectors, 712

scalecurve, 717, 718point, 715, 716solid, 722surface, 719, 720, 721vector, 723

sew surface, 571translate

coordinate frame, 778, 779curve, 693, 694, 695plane, 701point, 691, 692solid, 699, 700

surface, 696, 697, 698vector, 702

trim curve, 512vsum

curve, 763, 764point, 761, 762solid, 767surface, 765, 766

XYZcurve, 200point, 79, 80, 81solid, 202surface, 201

extend methodcurve, 488, 494, 497, 499surface, 551, 553, 555, 557, 559, 562, 564

extract methodcurve, 139, 143multiple points, 89, 91point, 84single point, 87

Fface, 11face method, 43field function, 4, 18fillet method

curve, 145fit method

curve, 149

Ggeneral trimmed surface, 21geometry types, 20global coordinate frame, 60global model tolerance, 19

surface gaps, 14grid, 25

Hhyperpatch, 25

IIGES, 3, 20, 25, 46

813INDEX

interpolate methodpoint, 94, 97vector, 434

intersect methodcurve, 151, 155intersect parameters subordinate form, 158point, 100

intersect parameters subordinate form, 158IsoMesh, 19, 24, 38

Lline, 25load/BC, 2loads/BC, 2

Mmanifold method

curve, 161match method

closing gaps, 15mathematical representation, 2mcoord method

curve, 732plane, 732point, 732solid, 732surface, 732vector, 732

merge methodcurve, 502refit, 506

meshing, 13mirror method


MSC.Patran CATIA, 47MSC.Patran ProENGINEER, 47, 54

.geo intermediate file, 56executing from MSC.Patran, 55executing from Pro/ENGINEER, 55

MSC.Patran Unigraphics, 47features, 47global model tolerance, 48user tips, 48

mscale methodcurve, 768point, 768solid, 768surface, 768

multiple pointsextract method, 89, 91

Nnative geometry, 3neutral file, 3, 25, 46, 57nodes, 808

renumber, 808nodes on curve

show action, 665nodes on point

show action, 656nodes on surface

show action, 670normal method

overview, 65

Ooffset method

constant curve, 171point, 110surface, 271variable curve, 173

Pp3_proe, 55parameterization

B-rep solid, 8curve, 5definition, 4point, 4solid, 8surface, 6trimmed surface, 7

parameterized geometry, 3


814

parametric axes, 16plotting, 18

parametric cubic equation, 25parametric cubic geometry, 57

definition, 25limitations, 26recommendations, 25, 26subtended arcs, 26

parametric curve, 20Parametric Technology, 2, 47Parasolid

tips for accessing, 49patch, 25PATRAN 2 Convention, 28, 29PATRAN 2 Convention button, 25, 28Paver, 38pentahedron, 43pierce method

point, 112pivot method


planemcoord method, 732mirror method, 724pivot method, 740position method, 749rotate method, 703translate method, 689

plane angleshow action, 680

plane distanceshow action, 682

point, 20delete action, 464equivalence method, 470extract method, 84interpolate method, 94, 97intersect method, 100mcoord method, 732mirror method, 724mscale method, 768offset method, 110pierce method, 112pivot method, 740position method, 749project method, 115rotate method, 703scale method, 713translate method, 689vsum method, 759XYZ method, 78

point distanceshow action, 642

point locationshow action, 640

point methodcurve, 120, 122, 125curve 4 point parametric positions

subordinate form, 129position method


pressure load, 4, 18, 35Pro/ENGINEER, 2, 47project method

point, 115

Rrectangular coordinate frame

definition, 60refit method

solid, 611renumber

action, 807

815INDEX

reverse method, 18, 34curve, 508solid, 352, 353, 616surface, 568

rotate methodcoordinate frame, 780curve, 703point, 703solid, 703surface, 703

Sscale method

curve, 713point, 713solid, 713surface, 713vector, 713

sew methodsurface, 570

show actioncoordinate frame attributes, 677curve angle, 661curve arc, 659curve attributes, 658length range, 663nodes on curve, 665nodes on point, 656nodes on surface, 670overview, 638plane angle, 680plane distance, 682point distance, 642point location, 640showing plane attributes, 679showing vector attributes, 684solid attributes, 675surface area range, 669surface attributes, 667surface normals, 672

show action information form, 639simply trimmed surface, 22single point

extract method, 87

solidblend method, 605break method, 589, 593, 598, 600, 602delete action, 464disassemble method, 608mcoord method, 732mirror method, 724mscale method, 768pivot method, 740position method, 749refit method, 611reverse method, 352, 353, 616rotate method, 703scale method, 713translate method, 689vsum method, 759XYZ method, 199

solid attributesshow action, 675

solidstype of, 24

spherical coordinate framedefinition, 62

subtract methodsurface, 572

suface normalsshow action, 672


816

surfaceblend method, 536break method, 518, 522, 526, 530, 532delete action, 464disassemble method, 539edge match method, 546, 549extend method, 551, 553, 555, 557, 559,

562, 564mcoord method, 732mirror method, 724mscale method, 768offset method, 271pivot method, 740position method, 749refit method, 566reverse method, 568rotate method, 703scale method, 713sew method, 570sharp corners, 34subtract method, 572top and bottom locations, 35translate method, 689vsum method, 759XYZ method, 199

surface area rangeshow action, 669

surface attributesshow action, 667

surface boundariesverify action, 786

surface method, 43surface normals, 18, 34, 41

example of aligning, 35

TTetMesh, 24, 25, 41tetrahedron, 43topologic entities

edge, 11face, 11vertex, 11

topological congruency, 31definition, 13gaps, 14

topologydefinition, 10ID assignment, 12, 13, 18

transform actionoverview, 686

translate methodcoordinate frame, 777curve, 689plane, 689point, 689solid, 689surface, 689vector, 689

trim methodcurve, 511, 514

trimmed surface, 20decomposing, 38default colors, 20definition, 20general trimmed, 21parent surface, 20simply trimmed, 22

tri-parametric solid, 8, 20, 24types of geometry, 27

curves, 28solids, 29surfaces, 29

Uupdate graphics subordinate form, 789

Vvector

interpolate method, 434mcoord method, 732mirror method, 724pivot method, 740position method, 749rotate method, 703scale method, 713translate method, 689

verify actionsurface boundaries, 786update graphics subordinate form, 789

vertex, 11

817INDEX

volume solid, 20vsum method

curve, 759point, 759solid, 759surface, 759

Wwedge solid, 43

XXYZ method

curve, 199point, 78solid, 199surface, 199


818

Patran 2010 Reference Manual Part 2: Geometry Modeling

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