基于下肢保护的保险杠结构参数多目标优化

Multi-objective Optimization of Bumper's Structure Parameter Based on Pedestrian Lower Limb Protection

参考国家标准,建立了下肢冲击器对汽车试验的有限元和多刚体模型,验证了两种模型仿真结果的一致性。在下肢冲击器对汽车试验的多刚体仿真模型中,选取保险杠结构参数作为设计变量,以膝部弯曲角度、膝部剪切位移、小腿上端加速度三个损伤指标值最小为优化目标,利用基于pareto最优的多目标遗传算法进行了优化设计,并对保险杠结构参数进行了灵敏度分析。仿真结果表明,保险杠离地高度对下肢损伤影响最大,由优化所得到的该组结构参数对下肢有较好的保护效果。

A multi-rigid body model and FE model of the Lower legform to vehicle test are h built according to national standard, venhed the consistency of two models. Using the multi-rigid model, structure parameters of the bumper is selected as design requirements. Taking the minimum value of the knee bending angle, knee shearing displacement and the acceleration measured at the upper end of the tibia as optimizing objective,the multi-objective genetic algorithm is applied based on pareto front. The sensitivity of the front structure to pedestrian＇s injury is analysed. Results show that the bumper central height mostly influence the lower limb injury; and the structure parameters obtained from the optimization have a good protection to the lower limb.