LMS Virtual.Lab – The Unified Environment for … Virtual.Lab Motion LMS Virtual.Lab Motion Auto...
Transcript of LMS Virtual.Lab – The Unified Environment for … Virtual.Lab Motion LMS Virtual.Lab Motion Auto...
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LMS SCADASMobile - Lab
LMS Virtual.Lab – The Unified Environmentfor Functional Performance Engineering
LMS Test.Lab LMS Virtual.LabMotion, NVH, Acostics, OptimizationLMS
Tec.Manager
LMS Engineering and Deployment Services
Technology TransferProcess Transformation
& Best Practices System Support
LMS Imagine.Lab OPTIMUSLMS OPTIMUS
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Strategy and Assumptions
CAD Data could have come from UGS, Pro-E, Solidworks, Autodesk, ParasolidsInterface with all FEA Tools, ABAQUS, NASTRAN, ANSYS, UGS - NX, PERMAS, or CATIA GPSModeled using a Scalable Approach without having to switch between different products.
Reasonably accurate results for early trade off studies vs. high accuracy for test correlationProvide option to choose between Medium Fidelity / Fast Solution vs. High Fidelity / Accuracy Leverage capabilities of the Virtual Lab Framework, Knowledgeware, Design Tables, Parameterization etc.
Highlight the techniques that can be used with Virtual Lab for support of a typicalPreliminary Design Decision Process.
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Process Flow – Drop Test
Tool for modeling and simulation of multi-disciplinary systems (hydraulic, pneumatic, thermal, mechanical, controls, etc.) Design of Oleo System1-D Representation of Landing Gear
Tool for 3-D Multi Body system designValidate Oleo system with 3-D Landing Gear Model and Flexible Modeling for Critical Components
Reuse AMESim Oleo System Model
Tool for FEA of ComponentsProvides Craig-Bampton modes for Flexible Bodies
LMS Virtual.Lab MotionLMS Virtual.Lab Motion
LMS Virtual.Lab MotionLMS Virtual.Lab MotionAuto FlexAuto Flex
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Drop Test Model – Oleo Dynamics
Starting Point :1D AMESim Model of Landing GearInitial Design of Oleo Damping
Validation:1D AMESim Model Oleo Hydraulics Reused by 3-D Motion Drop Test Simulation
Motion/Plant AMESim – “Coupled Equations”Motion Solver Integrates both sets of Equations
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*V_
α*
belt
wheel plane
ϕ*
ϕ γ
αV_c
C
residual springs
ΩV
z
Fx
wheel rim belt
Fz
effw
reff
eff. road plane actual road surface
Fy
Mzeffβ
ψ.
-
pac 2004
SWIFT model structure
Drop Test Model – Tire & Lift Forces
Tire ForcesCalculates & Applies forces at the tire contact patch between ground and wheel body in up to 3
directions when in contactChoice of tire model typically a trade off
• Level of accuracy required• Amount of test data available• Desired run times
Full library of tire forces available in Virtual.Lab Motion• Simple Tire• LMS Durability Tire• TNO – Swift Tire • Standard Tire Interface ( User Defined Tire)
Based on data provided & goals of the process, Simple Tire force was usedLift Force
3 Point force applied to aircraft in global z direction equal to total weight of aircraft + gearAircraft weight is parameter to this force
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Drop Test Model – Contact Forces
Large gaps present in Lug – Drag & Side Braces
Added to drop test model but required for Stress analysis portion
Virtual.Lab motion Contact forces used to simulate these gaps
Based on Hertzian formulation, very stable, fast & accurate
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Drop Test Model - Flexibility
FEA required to calculate mode shapes as inputTough choice about which FEA solver to use
Virtual.Lab Motion is compatible with a number of different solversCan “reuse” models between Drop Test &
Stress Analysis with any of these solversCraig-Bampton mode set drivers available
CATIA GPS chosen because of Auto Flex capability
Easiest setup of Flexible BodiesFully Associative with geometrySelect Rigid Body in mechanism model
the Mesh & FE load cases are automatically defined
2nd Craig-Bamption mode – 106Hz
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Process Flow – Stress Analysis
Reuse Flexible Drop Test model to generate BC for stress analysisDesign Tables & Configurations used to control modelGeometrically non-linear solution
Automatic component load transfer to CSA
Tool for FEA of componentsMultiple FEA solvers available to Virtual.Lab
Tool for DOE, Optimization, Reliability and Robust DesignUsed to calculate geometric sizing to achieve target stress
LMS Virtual.Lab MotionLMS Virtual.Lab Motion
LMS Virtual.Lab LMS Virtual.Lab OptimizationOptimization
LMS Virtual.Lab MotionLMS Virtual.Lab MotionAuto FlexAuto Flex
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Stress Analysis – Boundary Conditions & Load Transfer
Demonstrates how Virtual.Lab Motion models can be used to generate boundary conditions for FEABraking & Turning Analysis cases added to Drop Test model’s specification tree
Differences in topology controlled by Design Tables & Configurations
Virtual.Lab Motion Contact forces used to simulate gaps in Lug – Side & Drag brace connectionsOuter Cylinder was flexible, other bodies rigid
Side & Drag braces roughly the same sizeProblem thought of as being statically
determinateMajority of compliance assumed to be in
Contact forces between Lug – Side & Drag braces
Automatic load transfer in Motion transfers and sets up Static Analysis cases for CSA at any time step(s)
LMS Virtual.Lab MotionLMS Virtual.Lab Motion
LMS Virtual.Lab MotionLMS Virtual.Lab MotionAuto FlexAuto Flex
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Stress Analysis – Virtual Lab CSA ( CATIA GPS)
User choice for which FEA solver to useVirtual.Lab is compatible and scalable with
a number of different solversSame model used for Flexible bodies can
be used for stress analysisCSA had some advantages for this choice of process
Virtual Lab embedded, designer friendly FEA toolAuto flex & Load transfer capability with
Virtual.Lab MotionBest fit for the goals we established for this processParabolic tetrahedron elements usedGlobal mesh size 2in, local mesh size .25in
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Stress Analysis – Virtual.Lab Optimization
Virtual.Lab Optimization obvious choice for calculating geometric sizing to achieve target stresses
One integrated approach to “optimization”for all Virtual.LabFull accessibility to Virtual.Lab
parameterization (Knowledgeware)Applicable to any Workflow captured in
Virtual.Lab.1 pad and 2 fillets added to part
Engineering judgment & basic solid modeling skill required
Dimensions of these features input to OptimizationMax Principal stress for both load cases calculated by CSAObjective – Determine sizing to achieve Max Stress < 120ksi
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Stress Analysis Results
Starting Point:Outer Fillet Radius = 0.5inMax Principal Stress = 238.9 ksi
Optimization Result:Outer Fillet Radius ~ 2.25inMax Principal Stress = 114.7 ksi
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Process Flow – Stress Analysis & Torque Link Optimization
Advanced Geometric Wireframe, Surface & Sold Geometric modelerParameterized Length of Torque Link
Tool for FEA of components & assembliesMultiple FEA solvers available to Virtual.Lab
Tool for DOE, Optimization, Reliability and Robust DesignUsed to calculate geometric sizing to achieve targets
LMS Virtual.Lab LMS Virtual.Lab OptimizationOptimization
LMS Virtual.Lab StructuresLMS Virtual.Lab Structures
LMS Virtual.Lab GeometryLMS Virtual.Lab Geometry
FEA SolverFEA SolverAny Solver that supports Analysis Objectives
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Setting Up Optimization
Torque Link geometry modified so that length was driving parameterCAD Assembly was meshed using Virtual.Lab StructuresGap Connectors used to simulate complex load pathsVirtual.Lab compatible with a number of different FEA SolversVirtual.Lab Optimization used to determine optimum Torque Link Length
Torque Link Length was inputGoal was to minimize massMaximum Principal Stress was bound on Optimization
Torque Link Optimization
Braking Stress Before Optimization
Braking Stress After Optimization
Steering Stress Before Optimization Steering Stress After
Optimization