结合某自主品牌微型车开发项目,研究了乘用车的行人小腿碰撞保护设计。根据试验数据及工程开发经验,分析了行人小腿碰撞保护的影响因素,建立了有限元仿真分析模型,通过模拟计算,对该微型车前端的造型、相关部件结构进行了行人小腿碰撞保护改进设计。计算结果表明,改进后微型车的行人小腿碰撞保护性能显著提高,小腿胫骨加速度降低34%,膝部最大动态剪切位移降低57%,膝部最大动态弯曲角度降低67%,小腿碰撞保护的3项考核指标远低于国标限值,且满足Euro NCAP小腿保护高性能指标要求。

The pedestrian lower leg protection is an important issue in a vehicle design. Compared with the vehicle collision, the pedestrian protection collision energy is smaller, and the geometrical characteristics of the lower leg of the pedestrian will have great influence on the collision result. In this paper, the factors affecting the lower leg protection are analyzed, a design is proposed and validated with an example, in a test-correlated lower leg impact simulation. Calculation and analysis results show that by fine-tuning vehicle's shape and the structure design a good pedestrian leg protection design can be realized.