Yin Sha, Li Jiani, Xu Jun
Department of Automotive Engineering, School of Transportation Science and Engineering, Beihang University, Beijing, 100191, China; Advanced Vehicle Research Center (AVRC), Beihang University, Beijing, 100191, China.
Department of Automotive Engineering, School of Transportation Science and Engineering, Beihang University, Beijing, 100191, China; Advanced Vehicle Research Center (AVRC), Beihang University, Beijing, 100191, China,.
Accid Anal Prev. 2017 Sep;106:285-296. doi: 10.1016/j.aap.2017.06.005. Epub 2017 Jun 24.
In pedestrian-vehicle accidents, pedestrians typically suffer from secondary impact with the ground after the primary contact with vehicles. However, information about the fundamental mechanism of pedestrian head injury from ground impact remains minimal, thereby hindering further improvement in pedestrian safety. This study addresses this issue by using multi-body modeling and computation to investigate the influence of vehicle front-end shape on pedestrian safety. Accordingly, a simulation matrix is constructed to vary bonnet leading-edge height, bonnet length, bonnet angle, and windshield angle. Subsequently, a set of 315 pedestrian-vehicle crash simulations are conducted using the multi-body simulation software MADYMO. Three vehicle velocities, i.e., 20, 30, and 40km/h, are set as the scenarios. Results show that the top governing factor is bonnet leading-edge height. The posture and head injury at the instant of head ground impact vary dramatically with increasing height because of the significant rise of the body bending point and the movement of the collision point. The bonnet angle is the second dominant factor that affects head-ground injury, followed by bonnet length and windshield angle. The results may elucidate one of the critical barriers to understanding head injury caused by ground impact and provide a solid theoretical guideline for considering pedestrian safety in vehicle design.
在行人与车辆碰撞事故中，行人通常在与车辆发生初次碰撞后，会与地面产生二次碰撞。然而，关于地面碰撞导致行人头部受伤的基本机制的信息仍然很少，从而阻碍了行人安全的进一步改善。本研究通过使用多体建模和计算来研究车辆前端形状对行人安全的影响，从而解决这一问题。相应地，构建了一个模拟矩阵，以改变发动机罩前缘高度、发动机罩长度、发动机罩角度和挡风玻璃角度。随后，使用多体模拟软件MADYMO进行了一组315次行人与车辆碰撞模拟。设定了三种车速，即20、30和40公里/小时作为场景。结果表明，首要控制因素是发动机罩前缘高度。由于身体弯曲点的显著上升和碰撞点的移动，随着高度增加，头部与地面碰撞瞬间的姿势和头部损伤会发生显著变化。发动机罩角度是影响头部与地面损伤的第二个主要因素，其次是发动机罩长度和挡风玻璃角度。这些结果可能阐明了理解地面碰撞导致头部受伤的关键障碍之一，并为在车辆设计中考虑行人安全提供了坚实的理论指导。
