国人第 5 百分位女性行人下肢生物力学计算模型开发及应用

目的 预测与评估行人-汽车碰撞中小身材女性行人下肢的生物力学响应及损伤机制。 方法 基于符合国 人第 5 百分位女性特征的志愿者 CT 影像数据,重构具有详细解剖学结构的下肢几何模型,进行表面处理和网格化 后,构建下肢有限元计算模型。 重构动态三点弯曲尸体试验以及高速载荷下膝关节横向弯曲和剪切尸体试验,对 模型进行有效性验证。 应用该模型参照 Euro NCAP 技术公告 TB024 设置 4 组行人下肢-汽车碰撞仿真试验,探究 第 5 百分位女性行人下肢损伤机制。 结果 通过对比仿真试验与尸体试验结果,验证该模型具有较高的生物仿真 度。 在 4 种不同车型仿真试验结果中,SUV 车型对下肢损伤最轻。 小身材女性下肢股骨最易发生骨折,长骨最先 骨折,使得膝关节韧带未见损伤。 结论 本文所建下肢有限元模型作为国人第 5 百分位整人模型开发的一个重 要组成部分,为模型研发奠定基础。 研究结果对小身材女性行人损伤机制研究和行人保护装置研发有重要的应 用价值。

Development and Application for Biomechanical Computational Model of Lower Extremity of 5th Percentile Chinese Female Pedestrian

Objective To predict and evaluate biomechanical responses and injury mechanism of lower extremity for a small-sized female pedestrian in pedestrian-car collision. Methods The lower extremity geometric model with detailed anatomical structure was reconstructed based on CT images from the 5th percentile Chinese female volunteer. The finite element computational model was developed by optimizing the curved surface and meshing. The finite element model of pedestrian lower extremity was validated by reconstructing several cadaver tests, including dynamic three-point bending corpse experiments, and knee joint lateral bending and shearing cadaver experiments at high speed. Four simulation tests of pedestrian lower extremity-car collision as specified Euro NCAP TB024 were set up to investigate injury mechanisms of lower extremity of 5th percentile female pedestrian. Results The biomechanical computational model was validated to have high biofidelity by comparing the simulation test results with the cadaver test results. The lower extremity suffered the least injury in pedestrian- SUV collision. The femurs quickly fractured in simulations on four types of vehicle, so that no injury was found in knee ligaments. Conclusions This lower extremity finite element model is an important part of basic work for developing the 5th percentile Chinese female whole body computational model, which lays the foundation for model development. This study has important application values for studying injury mechanisms of female lower extremity and developing pedestrian protection devices.