Multi-objective lightweight optimization and design for body-in-white frontal sub-module

Lightweight optimization and design on body in white (BIW) has a significant effect on reducing emissions, fuel consumption, and protecting the environment. Much lightweight study on complete BIW and single BIW parts has been done in recent years. However, the lightweight study of sub-modules is difficult for considering the complete BIW performances. The efficiency of sub-module lightweight optimization based on complete BIW is not high. A new method is proposed to conduct frontal sub-module lightweight optimization. Firstly, the implicit parametric frontal BIW structure is constructed by SFE-CONCEPT software. Then, the coupling BIW model is constructed by combining the above frontal BIW structure and rear finite element structure. The shape and thickness variables are extracted from the frontal BIW structure, and the performance of complete BIW can be analyzed. The efficiency of constructing BIW and the complete performances are all considered by the new method. In addition, a modular method is adopted to analyze performance. It can achieve the concept of analysis leads design to conduct lightweight optimization and design for frontal structure by combining with ISIGHT software. After lightweight optimization and design of BIW frontal structure, the weight is reduced by 4.91 kg, which is as much as 5.70%. The performances have little change; the improved maximum performance is 3.32%, and the reduced maximum performance is 1.81%.