Constructing a Concept Vehicle Structure Optimized for Crashworthiness

Multi-disciplinary optimization (MDO) of a vehicle structure at the earliest stages of design is critical as OEMs are pressed to reduce the design time in order to respond to various demands from the market. MDO for the three essential areas of performance of the vehicle structure (NVH, Crash, and Durability) needs the throughput for each of the major disciplines to be approximately in the same range of turn-around time. However, crashworthiness simulation typically takes significantly longer than the others, making it difficult to include crashworthiness in the MDO. There have been many approaches to address crash simulation in a shorter time. The lumped mass-spring method is one of the approaches but has not been widely accepted since there are many difficulties in modeling and replicating the existing structure. It required physical or Finite Element tests for all structural components to get the spring properties, and then it is hard to convert the optimized spring properties into the real design of the structural components. In this paper, a reversed workflow is presented to construct the structure with the lumped mass-spring model and then find the proper component geometry with parametric optimization.