行人下肢有限元模型的建立与验证研究

下肢损伤是行人与车辆碰撞事故中的主要损伤形式之一，建立具有较高生物逼真度的行人下肢有限元模型，可以为下肢保护提供有效的研究手段.在下肢长骨（股骨、胫骨、腓骨）、韧带（ACL，PCL，MCL，LCL）及膝关节得到全面验证的基础上，建立了包含骨骼、韧带、肌肉及皮肤等详细解剖学结构的行人下肢有限元模型，并定义了各组织间的接触.利用行人下肢弯曲的生物力学实验，对下肢有限元模型进行了整体弯曲验证.结果显示，下肢有限元模型的损伤形式、损伤发生时刻、膝关节弯矩和弯曲角度均与实验结果吻合较好，能够较真实地反映行人下肢的损伤和生物力学响应，具有较好的生物逼真度.
Injury of the lower limb is one of the most common injuries in vehicle-to-pedestrian crashes. Therefore, accurate Finite Element (FE) models of pedestrian lower limb with high biofidelity play an important role in developing effective research techniques for the protection of the lower limb. The models of lower limb long bones (femur, tibia, and fibula), knee ligaments (ACL, PCL, MCL, LCL) and knee joint were fully validated in previous studies. On that basis, FE model of pedestrian lower limb, including skeletons, ligaments, muscles and skins, was developed, and contact properties among different tissues were defined. Based on the biomechanical experiments conducted by Kajzer et al., the FE model was validated against the whole pedestrian lower limb bending tests. The results have indicated that the injury types, injury occurring moments, knee joint bending moments and bending angles of the lower limb FE model are consistent with the experiment data. This model is capable of accurately reflecting the pedestrian lower limb injuries and biomechanical responses in impact processes with higher biofidelity.