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 optimization Parametric 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 & Shape Optimization Final Design Design Interpretation Different Iterations Intelligent System 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 Freedom Product definition ` Product Knowledge 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 Demo

Courtesy TECOSIM GmbH, Ruesselsheim ▲ Original bracket failed ▲ Reduce stress in bracket Topology Optimization Radiator Bracket – Design Package Space

Topology Optimization Radiator Bracket – Optimization Results Courtesy TECOSIM GmbH, Ruesselsheim

Topology Optimization Radiator Bracket – Geometry Extraction/Design Interpretation VOLUME = 0.3 Density Threshold = 0.6 Courtesy TECOSIM GmbH, Ruesselsheim

Topology Optimization Radiator Bracket – CAD Detailing of Concept Design Courtesy TECOSIM GmbH, Ruesselsheim

Design from Optistruct Final Interpreted Design Topology Optimization Radiator Bracket – Final Detailed Design Courtesy TECOSIM GmbH, Ruesselsheim

Topology Optimization Radiator Bracket – Design Validation Courtesy TECOSIM GmbH, Ruesselsheim Original Design Optimized Design 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

Mass (kg) Baseline Concept 1 Optimization of SUV Chassis Frame Analysis of First Concept Design

Cross-memberOpen C-Section Closed C-Section Optimization of SUV Chassis Frame Topology 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 Frame Second Concept Design -12% Mass (kg) Baseline Concept 2 Lighter Structure

Optimization of SUV Chassis Frame Optimal Design -23% Mass (kg) Baseline Final Design tuning using shape and size optimization

Optimization of SUV Chassis Frame Designs 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 ●Lightweight SUV Frame Concept –Baseline frame used for stiffness and modal targets

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 ●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 Weight Results

OMIS 661 Presentation – Intelligent System Case CAT Optimization Requirement: Max Principle Stress < 372 MPa Result: MPa Requirement: Von Mises Stress < 785 Mpa Result: 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?