关键词: 车身底板；落位变形；有限元仿真；结构优化；虚拟评估

Abstract: In the process of automotive product development, preliminary virtual assessment for each production stage can identify risks in advance, shorten the overall project development cycle, and reduce product development cost. This paper applies the finite element simulation technology to the handling process of the body-in-white assembly, predicts and analyzes the risk point of the drop deformation, and finds out the deformation risk near the positioning hole of the lower assembly. According to the analysis results, the optimization and improvement plan is proposed and verified by simulation. The verification results show that the product design optimization and the improvement of the connection process can effectively reduce the stress of the parts during the placement process, avoid the permanent placement deformation defect, ensure the strength of the vehicle and the positioning accuracy of the lower assembly, and reduce the cost of post-repair and debugging. It is significant to improve the level of intelligent manufacturing of car body and reduce manufacturing cost by identifying manufacturing quality risks in the early product design stage, guiding product design, and avoiding the flow of quality risks to the physical vehicle manufacturing stage.

Key words: Car body lower assembly; Drop deformation; Finite element simulation; Structure optimization; Virtual assessment analysis