Comparative Study on the Protective Performance of Typical Child Safety Seats Based on Experiments

Donghui Hao; Jie Zhang; Yi Qiang; Jianying An; Dechen Li

doi:10.15282/ijame.22.2.2025.12.0949

Authors

Donghui Hao School of Mechanical Engineering, University of Science and Technology Beijing, Beijing, China
Jie Zhang School of Mechanical Engineering, University of Science and Technology Beijing, Beijing, China
Yi Qiang China Academy of Machinery Science and Technology Group Co., Ltd., Beijing, China
Jianying An State Key Laboratory of Automotive Safety and Energy, Tsinghua University, Beijing, China
Dechen Li Alwaysrise (Hangzhou) Safety Technology Co., Ltd., Hangzhou, China

DOI:

https://doi.org/10.15282/ijame.22.2.2025.12.0949

Keywords:

Child restraint system (CRS), 5-point harness, 6-point harness, Child safety seat, Child occupant protection

Abstract

With the continued rise in global vehicle ownership, the safety of child occupants has garnered increasing research attention. However, United Nations Regulation No. 129 (UN R129) currently lacks injury assessment criteria for the crotch region—specifically, the perineal area and anterior pelvic soft tissues—primarily due to the absence of dedicated sensors in existing child anthropomorphic test devices (ATDs). To address this limitation, the present study proposes a qualitative evaluation method by placing quail eggs, chicken eggs, and modeling clay in the crotch region of a 3-year-old child dummy in order to observe deformation responses under crash loading. Comparative tests were conducted on child restraint systems featuring 5-point and 6-point harness configurations under frontal/lateral impact and overturning conditions in accordance with UN R129 protocols. The results indicate that the 6-point harness system significantly reduces soft tissue compression and mitigates the risk of pelvic injury during frontal impacts while also improving control of dummy kinematics in lateral impact and overturning scenarios. Overall, the 6-point harness demonstrated superior protective performance compared to the conventional 5-point system. These findings underscore the critical need to enhance protective measures for the perineal and lower pelvic regions in child occupants. The study further advocates for the development of child ATDs equipped with high-resolution crotch-area sensors and recommends integrating computational simulations with physical testing to establish a robust quantitative framework for evaluating injuries in the crotch region.

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