OMIS 661 Presentation – Intelligent System Case Caterpillar uses optimization to reduce structural...
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Transcript of OMIS 661 Presentation – Intelligent System Case Caterpillar uses optimization to reduce structural...
OMIS 661 Presentation – Intelligent System Case
Caterpillar uses optimization to reduce structural mass while improving structural strength
Presenters – Celeste Latham and John Kearsing
Agenda
•Concept Introduction
•Structural optimization
• Terminology
• Optimization process
• Caterpillar’s Virtual Product Development position
• Optistruct demo
• CAT optimization
OMIS 661 Presentation – Intelligent System Case Agenda
Structural optimization is an automated technique that derives the optimal design of a structure given design criteria.
Structural optimization has the potential to:.
–Significantly reduce material costs by optimizing structural designs with respect to specified goals
–Accelerate product development through the elimination of manual design and analysis iterations
–Improve product quality and reliability by promoting early and frequent analysis of structural strength and life
OMIS 661 Presentation – Intelligent System Case Concept Introduction
Material optimization Terminology
Topology optimization Optimal material layout in a given package space
Shape optimization Optimal Shape of a given geometric feature
Size optimizationParametric optimization
Ex. Gage thickness, Beam sections etc
OMIS 661 Presentation – Intelligent System Case Concept Introduction
OMIS 661 Presentation – Intelligent System Case Concept Introduction
Topology Optimization
Size & ShapeOptimization
Final Design
Design Interpretation
Different Iterations
Intelligent SystemIntelligent System
engineerengineer engineer
Structural Optimization Process
A Fortune 100 company, Caterpillar is the world's leading manufacturer of construction and mining equipment, diesel and natural gas engines and industrial gas turbines. The company is a technology leader in construction, transportation, mining, forestry, energy, logistics, electronics, financing and electric power generation.
Key company facts :
• ~$23,000,000,000 company
• ~69,000 employees
• Averages 500 patents per year
• Over 1000 PhDs/CEO PhD
OMIS 661 Presentation – Intelligent System Case CAT & VPD
OMIS 661 Presentation – Intelligent System Case CAT & VPD
• Every component on a CAT tractor is modeled in a 3D modeling system prior to creation – Millions of models. This has set the stage for Caterpillar’s Virtual Product Development Strategy.
OMIS 661 Presentation – Intelligent System Case CAT & VPD
• More time spent in the early stages of virtual product development to better reduce time spent maintaining the product in the later stages.
VIRTUAL PRODUCT DEVELOPMENT
Product design/refinement
Concept Detailed Design Testing
Accelerated Knowledge
FreedomProduct definition
`
Produ
ct Kno
wledge
OMIS 661 Presentation – Intelligent System Case CAT & VPD
VIRTUAL PRODUCT DEVELOPMENT
OMIS 661 Presentation – Intelligent System Case CAT & VPD
• Structural Optimization is one focus of VPD• Caterpillar is using Optistruct, a product developed by Altair Engineering, to help achieve
the goals of VPD
VIRTUAL PRODUCT DEVELOPMENT
Optistruct DemoOptistruct Demo
Courtesy TECOSIM GmbH, RuesselsheimCourtesy TECOSIM GmbH, Ruesselsheim
▲ Original bracket failed▲ Reduce stress in bracket
Topology OptimizationRadiator Bracket – Design Package Space
Topology OptimizationRadiator Bracket – Optimization Results
Courtesy TECOSIM GmbH, RuesselsheimCourtesy TECOSIM GmbH, Ruesselsheim
Topology OptimizationRadiator Bracket – Geometry Extraction/Design Interpretation
VOLUME = 0.3Density Threshold = 0.6
Courtesy TECOSIM GmbH, RuesselsheimCourtesy TECOSIM GmbH, Ruesselsheim
Topology OptimizationRadiator Bracket – CAD Detailing of Concept Design
Courtesy TECOSIM GmbH, RuesselsheimCourtesy TECOSIM GmbH, Ruesselsheim
Design from Optistruct Final Interpreted Design
Topology OptimizationRadiator Bracket – Final Detailed Design
Courtesy TECOSIM GmbH, RuesselsheimCourtesy TECOSIM GmbH, Ruesselsheim
Topology OptimizationRadiator Bracket – Design Validation
Courtesy TECOSIM GmbH, RuesselsheimCourtesy TECOSIM GmbH, Ruesselsheim
OriginalDesign
OptimizedDesign
Max. v. Mises Stress Max. Displ. Mass
Optimization of SUV Chassis Frame
Optimization Objectives:
Re-design the Chassis Frame Minimize the Mass Maintain the same structural stiffness
Optimization of SUV Chassis Frame
Identify the maximum design space
Topology Optimization
Optimization of SUV Chassis Frame
Optimal Placement of Material
Topology Optimization Result
Optimization of SUV Chassis Frame
First Concept Design
Evaluation of topology optimization result
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Optimization of SUV Chassis FrameAnalysis of First Concept Design
Cross-member
Open C-Section
Closed C-Section
Optimization of SUV Chassis FrameTopology Optimization of First Concept Design
Topology optimization on shell structure:
Re-define Material Placement
Cross-member
Closed C-Section
Open C-Section
Optimization of SUV Chassis FrameSecond Concept Design
-12%300
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ass
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Bas
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Lighter Structure
Optimization of SUV Chassis FrameOptimal Design
-23%300
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Design tuning using shape and size optimization
Optimization of SUV Chassis FrameDesigns Comparison
Baseline Frame:
Ladder Frame Design – 226 kg
Optimized Frame:
Lightweight Concept – 174 kg (-23%)
● Including Torsion Bar & Trans C/M
● Mass: 498(lbs) [226(kg)]**
Target Weight Reduction 125lbs (25%)
● Performance Targets:– Twist: 18.7 Hz
– Vertical Bend: 27.1 Hz
– Lateral Bend: 29.0 Hz
– Bending Stiffness: 3278 N/mm
– Torsion Stiffness: 121 kNm/rad** Includes mass of welds (3kgs)
Topology Driven Vehicle Concepts Topology Driven Vehicle Concepts
● Lightweight SUV Frame Concept
– Baseline frame used for stiffness and modal targets
Topology Driven Vehicle Concepts Topology Driven Vehicle Concepts
Define all available package space, Loading, and BC’s
Concept Development Process
Final Concept
Interpret into first concept design
Topology Optimization for gross concept features
Topology optimization for concept refinement
Interpret concept for final optimization and design details
Topology Driven Vehicle Concepts Topology Driven Vehicle Concepts
● Final Concept Design– Primary Hydroformed Sections– Mid-Rail “C” Section– Welded Body Mount Brackets– 23% lower mass– 25% fewer parts– 50% less weld length– Cost penalty:
• $0.25 cost per lb saved
● Performance Results:– Twist: 25.0 Hz (+34%)– Vertical Bend: 27.8 Hz
(+2.5%)– Lateral Bend: 26.4 Hz (-9%)– Bending Stiffness: 3278 N/mm (0%)– Torsion Stiffness: 159 kNm/rad (+31%)
OMIS 661 Presentation – Intelligent System Case CAT Optimization
D8 Trunnion optimization
OMIS 661 Presentation – Intelligent System Case CAT Optimization
Fabricated Version: Mass=44.1 Kg
Original Fabricated Trunnion Design – 2 pieces
OMIS 661 Presentation – Intelligent System Case CAT Optimization
Design Objective
Design Constraints
Minimized Weight
Max Principle Stress (Yellow Part) < 372 Mpa
Von Mises Stress (Yellow Part) < 785 Mpa
Design Variables-Five•Inside pocket•Neck Radius•Neck Transition•Bolt Plate Thickness•TRF Inserted Flange Thickness
OMIS 661 Presentation – Intelligent System Case CAT Optimization
Final Design
25
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Current Optimized
weight
weight
Weight(kg) % ReductionCURRENT
FABICATION DESIGN 44.1
OPTIMIZED DESIGN 26.6 39.70%
Weight Results
OMIS 661 Presentation – Intelligent System Case CAT Optimization
Requirement: Max Principle Stress < 372 MPa Result: 187.9 MPa
Requirement: Von Mises Stress < 785 MpaResult: 757.3 MPa
Max. Load
Stress Results
OMIS 661 Presentation – Intelligent System Case CAT Optimization
Financial Results
• 40 % weight reduction from current production design
• $136 cost savings per a part
• 3260 parts are expected
• $443,360 annual cost savings
OMIS 661 Presentation – Intelligent System Case CAT Optimization
Future Uses
•Expand the optimization process other product lines
•Gain an estimated savings of $2 million in 2005
OMIS 661 Presentation – Intelligent System Case CAT Optimization
Questions?