Multi-objective optimisation on crashworthiness of front longitudinal beam (FLB) coupled with sheet metal stamping process

Nowadays, improving the accuracy of vehicle collision simulation is of great significance to the design and manufacture safety automobiles. Many parts in automobile manufacture are obtained by stamping process. The thickness, plastic deformation and residual stress will change after stamping process which will affect the simulation precision of vehicle collision. However, traditional collision simulation does not consider the influence of these factors. In this paper, a collision simulation method of the front longitudinal beam was studied which maps the stamping results to a collision structure model. The effects of stamping on the crashworthiness of front longitudinal beam (FLB) were analyzed to improve the accuracy and effectiveness of the automobile crash finite element simulation. To further study the effects of the manufacturing parameters (e.g. the thickness of the sheet metal, friction coefficient and two draw-bead coefficients on the energy absorption and peak crushing force), a multi-objective optimisation was carried out with non-dominated sorting genetic algorithm (NSGA-Ⅱ) through combining the stamping and collision process. The optimal results of the FLB show that the proposed method significantly improved the formability and crashworthiness.