Multidisciplinary Analysis and Optimization of Vehicle Architectures Peter A. General Motors R&D and Planning Vehicle Development Research Laboratory Presented at MIT for 16.888/ESD.77J Multidisciplinary System Design Optimization (MSDO) Prof. Olivier de Weck and Prof. Karen Willcox. Designing Great GM Cars and Trucks!
Multidisciplinary Analysis and Optimization of Vehicle Architetctures Outline The vehicle design process Early stage vehicle design Vehicle architecture Parametric vehicle representation to support MAO Multidisciplinary analysis and optimization Engineering, manufacturing, business Example vehicle design problem MAO challenges General Motors R&D http://www.gm.com/company/careers/career_paths/rnd/lab.html Chemical & Environmental Sciences Reaffirming GM's environmental principles Electrical & Controls Integration Enabling electronics-based, driverfriendly, smart GM cars and trucks Manufacturing Systems Research Transforming the enterprise through math-based processes and systems Materials and Processes Adapting tomorrow's materials for today's automobiles Powertrain Systems Research Developing high-value, energy-efficient, highperformance powerplants and drivetrains Vehicle Development Research Speeding and enhancing engineering design and development
Vehicle Development Research Lab What do we work on? Safety Systems Lightweight Materials Work Systems CAE Methods Vehicle Design Virtual Reality Mechametronics Quality Methods Vehicle Design Design and Analysis Timeline Balance requirements System Analysis Detailed Analysis Aero dynamics Crash worthiness Structures Fuel Economy LD LR h LB LF b LA Solar Load Representation Occupant Dynamics Ride & Handling Other Analyses* LH FH FO WB RO Design freedom L STRUTS W/COILS HIGH ARM S LA NON-DRIVEN Component selection Part design Manufacturing design Topology design Parametric geometry Conceptual design Time Design detail (# design parameters) RH GC Detail design 3
Aerodynamics (ASD) Fuel Economy (EconoSTRAT) Database (MS Access) Structural Analysis (NASTRAN) Interior Roominess (Excel) Market Share (InSight) Design Representation (Unigraphics) BIW Cost (IBIS) Profitability (Excel) Facilities Investment (QuickStudy) Summary of Results (Excel) Multidisciplinary Optimization (isight) How Can MAO be Applied in Vehicle Design? Most effective application during early vehicle development Vehicle balance and integration This will be the focus of our discussion Can be applied in more detailed phases of design Example: tradeoffs for aerodynamics and structure Example: tradeoffs in component design Concept Description - Fuel economy - Wheelbase -Interior volume - Bending stiffness Example: Architecture Selection Problem New vehicle requirements Considerations Multiple derivatives/multiple requirements Vehicle performance Material/process strategy Financial/marketing Parametric Architectures #1 #2 #3 #4 #5 Design for profit 4 Profit by Architecture 3 2 Populated Databases - Architectures - Materials - Processes 1 0 Arch #1 Arch #3 Arch #5
Consider the Key Components of an MDO System Parametric Representation Templates Templates User Input Library Library Data Data Parametric Modeler Vehicle Database Discipline Modelers Elastic Structures Crashworthiness External Aerodynamics Solar Load Occupant Dynamics Suspension Loads Fuel Economy Other Analyses* Discipline Analysis & Sensitivity Calculations Results Database Multidisciplinary Optimization Parametric Design Representation The shared common representation is used to generate analysis input for ALL disciplines Need a single consistent representation for architecture and derivatives Combine UG geometry with non-geometric database UG parametric model BOM data - available/allowable components Marketing data
HIGH ARM SLA NON-DRIVEN Consistent Parametric Design Representation The shared common representation used to generate analysis input for ALL disciplines Geometric, non-geometric data Templates Data to be varied parametrically Stored in parametric CAD system Library data Data remains fixed (components) - location, orientation/location may change Parametric CAD system Auxiliary database information User input Selection and location of components, settings of dimensional parameters P=63 P=125 Parametric Design Representation Combines Parametric geometry (Unigraphics) Non-geometric configuration data (MS Access) Many parameters available High level architecture variables Detail level component variables BL WR T W H LR LB LD h LA LF b LH FH RH GC FO L WB RO
Parametric Geometry Driving Discipline Analysis High level input parameters Wheel base Overhangs Axle positions Width... Resulting geometry used for: Packaging Occupant, section dimensions, BOM items, Measures Areas, lengths, volumes, angles, Aerodynamics. Parametric Geometry Parametric Dimensions and Occupant Placement