汽车追尾碰撞中颈部姿态对生物力学响应的影响

Effect of neck posture on biomechanical response in rear end collision

基于中国人体5百分位女性志愿者CT图像数据,构建具有详实解剖学结构的颈部有限元模型,重构志愿者实验验证其有效性,并构建颈部伸展和屈曲姿态模型。参照中国新车评估规程(C-NCAP)鞭打试验,对3种不同姿态颈部模型分别施加加速度曲线,研究驾乘人员颈部不同姿态时的生物力学响应。结果表明:自然姿态下最大应力出现在C7椎体和寰椎与枕骨大孔间的前纵韧带及寰枢关节的囊韧带,椎间盘最大应力出现在C6-C7椎段,且颈部损伤准则(NIC)值和颈部保护准则值(N_(km))均达到阈值。伸展姿态下最大应力出现的位置与自然姿态一致,但是其应力值和N_(km)值在3种姿态中最小。屈曲姿态皮质骨最大应力出现在枢椎齿凸和寰枢关节的囊韧带处,但NIC值在3种姿态中最小。该研究对汽车主动头枕的研发及未来自动驾驶中乘员颈部处于休闲姿态时的碰撞防护措施开发具有一定的参考价值。

Based on the CT image data of Chinese 5th percentile female volunteers,a finite element model of neck natural posture with detailed anatomical structure was constructed,and its effectiveness was verified by reconstructing volunteer experiment.The neck extension and flexion posture models was constructed.According to the China-New Car Assessment Program(C-NCAP)whiplash test,the acceleration curves of three neck models with different postures were applied respectively to investigate the biomechanical response of drivers and passengers with different postures.The results show that in natural posture,the maximum stress appears in C7 vertebral body,anterior longitudinal ligament between atlas and foramen magnum,and saccular ligament of atlantoaxial joint;the maximum stress of intervertebral disc appear in C6-C7 vertebral segment,and NIC and N_(km) values reach the threshold.The maximum stress in extended posture is the same as that in natural attitude,but the stress value and N_(km) value are the least of the three postures.In flexion posture,the maximum stress of cortical bone appears at the saccular ligament of axis odontoid and atlantoaxial joint,but NIC value is the smallest among the three postures.This research has a certain reference value for the research and the development of vehicle active headrest and the collision protection measures when the occupant’s neck is in leisure posture in future automatic driving.