Topology and modular size optimization of small electric vehicle frame based on cross-section contribution analysis

In this paper, a cross-section contribution analysis (CSCA) method is proposed to optimize the size of a truss frame. A finite element model of the initial truss frame was established to analyze the static-dynamic stiffness and the full load strength. The reliability of the model was then verified by experiments. An improved wireframe model was obtained from the secondary design of the topological conceptual model, and the contribution rate (CR) of each tube to the performance was analyzed. A “modular line” was defined to modularize the frame tubes based on the cross-section CR (CSCR). The performance and light weight of the modular frames (MFs) with different tube layout schemes were studied. The results of modular size optimization show that the optimized truss frame for small electric vehicles (EVs) reduces the weight and improves the performance significantly. In addition, this method can have better results in continuous variable optimization (with non-standard tube size) as a reference for industry. In discrete variable optimization (with standard tube size for manufacturing feasibility), the method could greatly shorten the development cycle and lead to production rapidly.