Top-Down Design Tools Managing Complex Assemblies
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Transcript of Top-Down Design Tools Managing Complex Assemblies
Top-Down Design ToolsManaging Complex Assemblies
Victor RemmersHolland Engineering Consultants BV
Tips & Techniques
© 2006 PTC2
Top-Down Design Philosophy
© 2006 PTC3
Traditional Design Approach
“Bottom-Up Design”
Design of individual components independent of the assembly
Manual approach to ensure that components fit properly and meet the design criteria
Components and those placed in sub-assemblies are brought together to develop the top-level assembly
Errors are manually identified and modifications to each component are made to make the adjustment. As assembly grows, detecting these inconsistencies and correcting them can consume a considerable amount of time
Top Level Top Level AssemblyAssembly
ComponentComponentDesignDesign
ComponentComponentDesignDesign
ComponentComponentDesignDesign
© 2006 PTC4
Possible example Bottom Up?
Mate
© 2006 PTC5
Top-Down Design Philosophy
“Top-Down Design”
Method of placing critical information in a high-level location
Communicating that information to the lower levels of the product structure
Capturing the overall design information in one centralized location
DesignDesign InformationInformation
ComponentComponent ComponentComponent ComponentComponent
© 2006 PTC6
A more integrated approach….
© 2006 PTC7
Top Down Design Stages – It is a concept.
6-Stage Process
1. Conceptual Engineering Phase
Layouts and Engineering Notebook
2. Preliminary Product Structure Phase
Pro/INTRALINK, Model Tree
3. Capturing Design Intent Phase
Skeleton Models
4. Manage Interdependencies Phase
Reference Viewer & Reference Graph
5. Communication of Design Intent Phase
Copy Geoms, Publish Geoms & Shrinkwrap
6. Population of the Assembly Phase
Automatic Component Constraints & Component Interfaces
© 2006 PTC8
The Bobcat example
© 2006 PTC9
Conceptual Engineering PhaseLayouts and Engineering Notebook
Understand Existing Situation
High-level Requirements
Space Allocation
Define New Space and Motion
2D Sketches
3D Models
Rapid Iteration & Convergence
Animations
Capture Key Design Intent
Parameters
Notes
Spreadsheets
Proprietary Data
Stage 1
© 2006 PTC10
Preliminary Product Structure Phase Pro/INTRALINK, Model Tree
Quickly define product hierarchy
• Before any of the components’ geometry is defined
Intuitive, automatic mapping to “start models”
• Templates ensure all designs share the necessary common elements such as layers, views & parameters
Foundation for efficient task distribution
Assembly Population Environments
• Pro/E menus and Model Tree pop-up menus
• Pro/INTRALINK and PDMLink
Component Creation Methods
• Empty Components; Copy from start models
• Automatic assembly of default datums
• Unplaced, Partially- & Over-Constrained Components
Stage 2
© 2006 PTC11
Capturing Design Intent Phase Skeleton Models
What needs to happen?
Capture conceptual design parameters within the context of the assembly
Capture & control critical object interfaces in a single, convenient location
How? Skeleton Models…
Centralized pathway for communication
Facilitate task distribution
Promote well-organized design environments
Enable faster, more efficient propagation of change
Special Treatment in BOMs, Simplified Reps, Drawings, Model Tree & Mass Property Calculations
Uniquely supported Scope Control Setting
Stage 3
© 2006 PTC12
Manage Interdependencies PhaseReference Viewer & Reference Graph
Stage 4
Tools to Manage References
External Reference Control
•Ensures Top-Down Design methodology is followed
• Incorporate design management rules directly into the design
•Ensures proper design reuse
Pro/INTRALINK
Model Tree
Global Reference Viewer
Reference Graph
© 2006 PTC13
Communication of Design Intent Phase Publish Geoms, Copy Geoms & Inheritance
Publish Geometry Features
Provides ability to pre-determine the geometry to be referenced by a Copy Geometry feature
Allows designers to define their interfaces to the rest of the design
Copy Geometry Features
Allows copying of all types of geometry
Surfaces, edges, curves, datums, quilts, copy/publish geometry
Retains copied geometry name and layer settings
Dependency on parent geometry can be toggled
Can be “Externalized”
External Copy Geometry
Build relationships on external models independent of an assembly
Useful for coordinate system assembly practices
Inheritance – Inherit model geometry for one-way associativity
Shrinkwrap (included in Foundation Advantage Package)
Stage 5
© 2006 PTC14
Population of the Assembly PhaseAutomatic Component Constraints & Component Interfaces
Stage 6
What tools are available for populating the assembly?
Assembly Tools
• Drag & Drop Placement
• Component Interfaces
Component Creation
• Within the context of the assembly
• Mirror Parts or Subassemblies
© 2006 PTC15
How does Top Down Design relate to company goals?
Four Goals from Upper Management
1) Cycle Time Reduction.
2) Increase User Satisfaction with Software.
3) Margin Increase.
4) Cost Reduction.
Four Goals from Upper Management
1) Cycle Time Reduction.
2) Increase User Satisfaction with Software.
3) Margin Increase.
4) Cost Reduction.
© 2006 PTC16
Why should you use it?
Benefits:
Reduced design time
Reduced errors (right the first time)
Increased quality
Better project management visibility
Concurrent engineering
Confidence in top-level regeneration
Knowledge of how modules interface
Top-level change control
Benefits:
Reduced design time
Reduced errors (right the first time)
Increased quality
Better project management visibility
Concurrent engineering
Confidence in top-level regeneration
Knowledge of how modules interface
Top-level change control
© 2006 PTC17
Example: to design an alternator...
What information should a designer need to work with most times?
Complete Top-Level Assembly
540 MB
All Skeleton Models in Top-Level
Assembly
70 MB
Neighboring Subassemblies
320MB
Subassembly, with Skeleton Model containing
all required information ~ 20 MB
© 2006 PTC18
What does an example look like?
Three PhasesPro/INTRALINKPro/CONCEPTISDX Pro/ENGINEERPro/NOTEBOOK
CONCEPTUAL DESIGN
CAPTURE DESIGN CRITERIA
DETAILED DESIGN
© 2006 PTC19
Product Definition
© 2006 PTC20
Product Definition: Engineering Layout
What it is: First thing done in design cycle First thing done in design cycle
What it is Not:What it is Not:
Used to evaluate key interface points Used to evaluate key interface points
Used to evaluate key components of project Used to evaluate key components of project
Three dimensional solids Three dimensional solids
Fully detailed Fully detailed
© 2006 PTC21
Advantages of Using a Layout
Document design information in one centralized location
Document design information before creating solid models
Investigate design options without involving the entire assembly
Easily make design changes because all of the design information is contained in one location
© 2006 PTC22
#2 Product Definition: Assembly Structure
What it is: Virtual Assembly / BOM Virtual Assembly / BOM
What it is Not: What it is Not:
Used to organize assembly & assigning of design tasks Used to organize assembly & assigning of design tasks
Used to input non-geometrical data up-front Used to input non-geometrical data up-front
Three dimensional solids Three dimensional solids
Fully detailed Fully detailed
Fully constrained Fully constrained
© 2006 PTC23
Advantages of Defining Preliminary Product Structure
Defining the product structure prior to defining geometry can assist you in organizing the assembly into manageable tasks that can be assigned to design teams or individual designers.
Associate specific library parts (that are to be used on the project) with the assembly at the start of the design, preventing confusion later.
© 2006 PTC24
Advantages of Defining Preliminary Product Structure
Cont…
Submit the assembly to Pro/INTRALINK or PDMLink and assign models to the appropriate vaults or folders.
Individual designers can focus on specific design tasks instead of on how their design is going to fit into the overall structure.
Input non-geometrical information such as the part number, designer’s name, etc., at a very early stage.
© 2006 PTC25
#3 Product Definition: Skeletons
What it is: Zero-mass geometry Zero-mass geometry
What it is Not: What it is Not:
Exact location detail Exact location detail
Three dimensional solids Three dimensional solids
Fully detailed Fully detailed
Minimized geometric detail Minimized geometric detail
© 2006 PTC26
And Definitely Not This!!
© 2006 PTC27
Advantages of Using Skeletons
Provides a centralized location for design data
Simplifies assembly creation / visualization
Aids in assembling mechanisms
Minimizes unwanted parent-child relationships
Allows you to assemble components in any order
Controls propagation of external references
© 2006 PTC28
Central source for information
Benefits of Communicating Information From a Central Source
Task distribution
Concurrent Modeling
Managing External References
Tools Declaration
Publish Geometry
Copy Geometry
© 2006 PTC29
Hierarchy
Top_level.asm
Top_level_skeleton.prt
Sub_assy_1.asm
Sub_assy_1_skeleton.prt
Sub_assy_2.asm
Sub_assy_2_skeleton.prt
Sub_assy_x.asm
Sub_assy_x_skeleton.prt
© 2006 PTC30
3D Design … Finally!
The foundation is set … but topologically modifiable … it’s time for 3D.
With Reference Control Manager, you are safe to create your parts directly in the assembly.
© 2006 PTC31
More Than Meets The Eye!
Interchangeability:
Family of Tables
Interchange Assembly
Layout Declarations
© 2006 PTC32
Power of Top-Down Design
To Achieve Advanced Automation, consider using:
Relations
Pro/Program
© 2006 PTC33
Miscellaneous Tips
Separate Part Versus Assembly for Skeleton Features
Avoid constructing assembly-level skeleton features since the system requires that you perform all edits of these features in Assembly mode.
• The components can become an obstruction and degrade performance.
• Furthermore, you cannot easily reuse skeleton features at the assembly level in other subassemblies. By using a separate part file, you can edit the feature in Part Mode and reassemble it into many different assemblies.
Geometry Features
Place all static information in a skeleton as early as possible and place all dynamic information later in the design process cycle.
© 2006 PTC34
Miscellaneous Tips
Datums for Skeleton Models
Consider renaming skeleton datums to “sk_”
Visualization
Use simplified reps and transparency prolifically to make viewing easier
Use “display states” to highlight different items at different times
Use surfaces to clarify meaning of centerlines & axes
Conceptualization
Don’t be afraid to use simple hand sketches before delving into complex situations … it’s NOT illegal
© 2006 PTC35
Pro/E Wildfire EnhancementsHigh-performance Assembly Modeling
Lightweight Components
Represent common components with lightweight graphics for optimum display speed
Accurate mass properties and BOMs
Customizable symbolic representations
Flexible Components
Represent multiple states of a single component in an assembly
Addresses critical need for consistency between BOM and assembly model
Intelligent Regeneration
Assembly regeneration is up to 80% Faster!
© 2006 PTC36
Highlights of Top-Down Design
Capture knowledge, or design intent, allowing you to concentrate on significant issues by making the software perform tedious, repetitive calculations.
Enable the framework for interchangeability of components allowing for high-velocity product development by supporting rapid iterations of product variations.
Create a concurrent design environment by spreading project design responsibility across many organizational levels.
© 2006 PTC37
New in Advanced Assembly in Wildfire 3.0
Data Sharing Dashboard
The Data Sharing dashboard consolidates the Merge, Cutout, and Inheritance features in a modern user interface.
Enhancements to Data Sharing features in a new dashboard offer many benefits:
• Allows changing of multiple feature types at any point
• Offers a user-friendly user interface with easy access to commands
• Supports object-action workflow for increased productivity
• Consolidates Data Sharing features, such as Merge, Cutout, and Inheritance
© 2006 PTC38
New in Advanced Assembly in Wildfire 3.0 (#2)
Top-Down Design with Mechanism Assemblies
You can now design a skeleton model that includes motion.
Motion skeletons are available in Assembly, allowing motion to be incorporated into the model at the beginning of the design process. There is no longer a need to recreate an assembly to include a mechanism analysis.
You can create mechanism bodies and connections as a motion skeleton, then run a simple kinematic analysis to ensure that the skeleton provides the appropriate degrees of freedom. You can then create and assemble components to the motion skeleton. Motion skeletons are defined in the same way as normal assembly skeletons and include reference control settings. They do not appear in the assembly bill of materials.
© 2006 PTC39
POWER OF TOP DOWN DESIGN!!!