正面碰撞中汽车儿童约束系统模型的建立及改进

Development and Improvement of An Automotive Child Restraint System Model for Frontal Crashes

针对目前儿童座椅常存在因结构设计不合理而导致的保护效果差的问题,基于MADYMO建立了包含台车座椅、某款典型儿童座椅、五点式安全带、P3儿童假人的儿童约束系统模型,根据GB 27887标准进行正面碰撞台车试验,基于试验结果从假人运动轨迹和损伤指标两方面对模型进行了验证。结果表明,建立的儿童约束系统模型能较真实地反映实车碰撞过程,具有较高的准确性。在模型验证的基础上,针对碰撞中座椅上部存在变形量过大的问题,提出了在椅背顶部后侧加装加强板,并将椅背与椅盆连接处位置原有的凹槽贯通的改进方案,对改进后的儿童座椅进行了不同加速度下正面碰撞工况的仿真分析和安全性评估。结果表明,改进方案能在座椅质量不增加的前提下,有效减少椅背的变形量,确保碰撞中座椅结构的完整性和儿童的安全,达到了预期的防护效果。研究结果可为儿童座椅的设计和改进提供支撑和参考。

The use of child seats reduces the risk of injuries to children in automobile accidents.However,many current child seats provide poor protective effect due to improper structural design.In this study,a child restraint system(CRS)model,including a sled seat,a typical child seat,a five-point seat belt and the P3 child dummy,was developed based on MADYMO.The model was validated by comparing the dummy's motion trajectory and injury metrics with the results of the frontal impact sled tests conducted in accordance with GB 27887.The results show that the developed CRS model can reflect the real vehicle collision process with a high degree of accuracy.In order to solve the issue of excessive deformation in the upper part of the seatback during a collision,an improved design strategy was proposed which involves installing a reinforcing plate on the deformation region and creating holes at the bottom of the seatback.The performance of the improved design strategy in protecting the child under different acceleration conditions for frontal collisions was evaluated based on the validated CRS model.The results show that the improved strategy can effectively reduce the amount of deformation in the seatback without increasing the seat mass.It ensures the structural integrity of the seat and the child's safety during a collision,thereby achieving the expected protective effect.This study provides useful guidance for the design and improvement of new child seats.