基于3D激光扫描、多刚体重建和遗传算法优化的车-人碰撞事故再现模拟与损伤分析

目的利用3D激光扫描技术,结合多刚体动力学和遗传算法优化对一起汽车与自行车及其骑车人碰撞的交通事故进行再现模拟与损伤分析,为法医学死因鉴定提供生物力学依据。方法利用3D激光扫描技术对肇事汽车进行测量,根据测量数据建立人-自行车-汽车多刚体模型,并设置优化变量的取值范围,利用多目标遗传算法,带精英策略的快速非支配排序遗传算法求最优近似解,并与事故现场附近监控视频记录进行比较。结果事故车辆激光扫描重建结果良好,通过遗传算法优化收敛所获得的最优近似解中的假人、自行车、汽车的动力学行为与监控视频中所记录的三者动力学行为相符合,假人的损伤参数也与事故中骑车人的损伤情况及部位相一致。结论利用3D激光扫描技术,结合多刚体动力学和遗传算法优化可以对人-自行车-汽车碰撞前的运动状态、碰撞致伤过程进行重建,并对受害者的损伤进行力学分析,在交通事故受害人致伤方式鉴定及死因分析中具有应用价值。

Reconstruction of Vehicle-human Crash Accident and Injury Analysis Based on 3D Laser Scanning,Multi-rigid-body Reconstruction and Optimized Genetic Algorithm

Objective To reconstruct a vehicle-bicycle-cyclist crash accident and analyse the injuries us-ing 3D laser scanning technology, multi-rigid-body dynamics and optimized genetic algorithm, and to provide biomechanical basis for the forensic identification of death cause. Methods The vehicle was measured by 3D laser scanning technology. The multi-rigid-body models of cyclist, bicycle and vehicle were developed based on the measurements. The value range of optimal variables was set. A multi-ob-jective genetic algorithm and the nondominated sorting genetic algorithm were used to find the optimal solutions, which were compared to the record of the surveillance video around the accident scene. Re-sults The reconstruction result of laser scanning on vehicle was satisfactory. In the optimal solutions found by optimization method of genetic algorithm, the dynamical behaviours of dummy, bicycle and ve-hicle corresponded to that recorded by the surveillance video. The injury parameters of dummy were consistent with the situation and position of the real injuries on the cyclist in accident. Conclusion The motion status before accident, damage process by crash and mechanical analysis on the injury of the victim can be reconstructed using 3D laser scanning technology, multi-rigid-body dynamics and opti-mized genetic algorithm, which have application value in the identification of injury manner and analysis of death cause in traffic accidents.