汽车-行人碰撞事故再现自动优化方法

Automatic Optimization Method for Vehicle-pedestrian Collision Accident Reconstruction

为了提高事故鉴定的效率和客观性,提出基于数值仿真的汽车-行人碰撞事故再现的自动优化方法。该方法基于汽车-整体行人假人碰撞的多刚体动力学仿真,通过将仿真值与实测值进行比较,自动调整仿真输入,得到最优的碰撞初始条件,从而再现整个事故的全过程。针对不同类型事故的优化问题,分析相应的优化模型,提出以汽车碰撞速度或制动延迟时间为优化变量,以人体损伤为约束条件,利用行人和汽车的停止位置信息构成目标函数。由于采用序列线性规划法为优化算法,同时兼顾了基于人车停止位置和人体损伤的事故再现方法,所以能较好地适应人车碰撞事故再现的非线性特点。利用商业化优化工具,应用上述方法对一起真实案例进行再现分析。并且,通过比对人体损伤的法医鉴定结果,以及目标函数响应面分析,验证该方法的可行性。

To improve the efficiency and objectivity of accident judgments, an automatic optimization method of vehicle-pedestrian accident reconstruction based on numerical simulation is proposed. In this method, the accident process is reconstructed based on full scale dummy multi-body simulation, and its initial conditions are automatically adjusted to optimum solution which can generate the best match between simulation and real accident data. For several types of pedestrian accident, the corresponding optimization model is presented in which the impact speed and/or the braking delay are regarded as the design variables and the displacement of vehicle and pedestrian is used to construct the objective function with the constraints of pedestrian injuries. Because sequential linear programming is used as the optimization algorithm and the optimization is based on rest position as well as pedestrian injury, the above mentioned method is suitable for the nonlinearity of pedestrian accident reconstruction. Using the commercial software, the method is applied to a real-world pedestrian accident in order to prove its feasibility. The simulation is compared with the autopsy report in terms of several pedestrian injuries. Also, the global response surface of the objective function constructed by a full factorial experimental design is used in the evaluation.