Systematic Approach for Structural Optimization of Automotive Systems

In today’s cost-competitive automotive market, use of finite element simulations and optimization tools has become crucial to deliver durable and reliable products. Simulation driven design is the key to reduce number of physical prototypes, design iterations, cost and time to market. However, simulation driven design optimization tools have struggled to find global acceptance and are typically underutilized in many applications; especially in situations where the algorithms have to compete with existing know-how decision making processes. In this study, systematic multi-phase approach for optimization driven design is presented. Approach includes three optimization phases. In first phase, topology optimization is performed on concept BIW design volume to identify critical load paths. Architectural inputs from topology are used to design base CAD. Optimization phase two consists of 1) topography (bead) optimization to increase panel stiffness and 2) Section optimization through Multi-disciplinary optimization (MDO). Sections, member positions, thickness and bead pattern of panels are optimized in this process. After phase two, CAE iterations done to meet performance requirements from multiple domains lead to small weight addition. Optimization phase three is performed on CAD release prior to start of tooling development and focuses on weight reduction. Case study of this multi-phase optimization approach on automotive body in white (BIW) is presented highlighting key benefits at each stage.