乘用车前挡风玻璃角度对行人头部/颅脑损伤影响研究

Influence of windscreen inclination angle on the head/brain injury in a pedestrianimpact accident

头部/颅脑损伤在车辆与行人碰撞事故中频繁发生,而行人头部与挡风玻璃的碰撞是导致头部损伤的主要原因。旨在采用数值模拟方法研究乘用车挡风玻璃倾斜角度对行人头部/颅脑损伤的影响。采用TNO多刚体行人模型和THUMS4.0头颈部有限元模型耦合得到新的行人碰撞数值模型,并结合已有的多刚体乘用车模型,借助真实的行人碰撞交通事故案例对该耦合模型进行基于人车动力学响应的有效性验证。在此基础上,构建人车碰撞模型矩阵,其中挡风玻璃角度的变化范围设定为24°~50°(间隔为2°),车辆速度设置为45 km/h,行人与车辆碰撞位置时分别处于车辆前保险杠前端1/2和1/3处。分析结果表明,该耦合模型可以较准确地再现事故中的行人动力学响应;行人碰撞保险杠前端中间(即1/2处)位置时的头部损伤较1/3处更严重;头部损伤在本文所分析的变化范围内随挡风玻璃角度的增加呈先减小后增加的变化趋势,且当挡风玻璃角度位于32°~34°左右时损伤风险较低。

The head/brain injury occurs frequently in a car-to-pedestrian impact accident.The impact between the pedestrian head and the windscreen is a leading cause of the head/brain injury.The effect of windscreen inclination angle of a typical small passenger car on the pedestrian head/brain injury was numerically investigated.The THUMS(Total HUman Model for Safety,developed by Toyota Central R&D Labs)head-neck finite element(FE)model and TNO multi-body(MB)pedestrian model were coupled to construct a new numerical pedestrian impact model.By simulating a real-world car-to-pedestrian impact accident,the new coupled model was validated in terms of the pedestrian/vehicle kinematics reconstruction of such accident.Based on the above model,the impact simulation matrix was set up,the variation range of the windscreen inclination angle was set to be 24°—50°(an increment of 2°),the impact locations of the pedestrian with the vehicle were defined as the 1/2 and 1/3 of the front of the bumper,and the impact velocity was considered to be 45 km/h.The results show that the coupled pedestrian model could predict the pedestrian kinematics effectively.The predicted head/brain injury when the pedestrian is impacted at the 1/2 of the bumper seems to be more severe than at the 1/3 location.It is also suggested that the head/brain injury risk decreases firstly and then increases with the increasing windscreen angle within the predefined range,and the angle between 32°—34°produces the lowest head/brain injury risk.