Injury and protection of child occupants in small overlap impact by booster CRS

doi:10.3969/j.issn.1674-8484.2020.04.003

Abstract

Abstract:

The risk of injury and protective measures for 6-year-old child occupants were investigated by using a high-backed booster child restraint system (CRS) in small off-set crashes in automobiles. Based on the 2017 version of the Insurance Institute for Highway Safety (IIHS) test protocols, a THUMS 6YO Human FE (finite element) model was used to develop a front impact FE model of rigid wall with 25% overlap rate of automobile. The kinematic behaviors of the FE models were compared and analyzed, as well as the injury parameters of head and chest resultant acceleration. The results show that the 6-year-old children have both forward and lateral displacement in the small overlap impact; The accelerations of the head and the chest of child occupant under the backless booster CRS were larger than those under the high-backed booster CRS with a declination motion. The optimized child restraint system makes the seatbelts with load limiter being better than that of inflatable seatbelts in reducing the crew's combined chest acceleration and rib fracture risk during a collision, but with increasing head injury risk of some degree.

Key words: small overlap impact of vehicle, booster, child restraint system (CRS), restraint system, finite element (FE) simulation

CLC Number:

U463.1

HAN Yong, LÜ Chuncheng, TANG Bin, HUANG Hongwu, LUO Jiesi, YU Yi. Injury and protection of child occupants in small overlap impact by booster CRS[J]. Journal of Automotive Safety and Energy, 2020, 11(4): 444-453.

Figures/Tables 19

References 28

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关键字	含义	参数值
SBRID	限力器ID	1
SBID	第一个伸出限力器的安全带单元ID	89 804 591
SID	传感器（用于触发限力器工作） ID	1
TDEL	传感器触发后的时间延迟	5 ms
PULL	延迟阶段,安全带伸出限力器的长度	10 mm
LLCID	限力器的加载曲线ID	1
ULCID	限力器的卸载曲线ID	2
LFED	防止安全带初始松弛而吸入限力器内部的安全带长度	12 mm

关键字	含义	参数值
SBRID	限力器ID	1
SBID	第一个伸出限力器的安全带单元ID	89 804 591
SID	传感器（用于触发限力器工作） ID	1
TDEL	传感器触发后的时间延迟	5 ms
PULL	延迟阶段,安全带伸出限力器的长度	10 mm
LLCID	限力器的加载曲线ID	1
ULCID	限力器的卸载曲线ID	2
LFED	防止安全带初始松弛而吸入限力器内部的安全带长度	12 mm

关键字	含义	参数值
VSCA	体积缩放系数	1
PSCA	压力缩放系数	1
VINI	初始体积	0
MWD	质量阻尼系数	0
SPSF	滞点压力系数	0
CV	定容热容量	1.700 MJ·(kg·K)^-1
CP	定压热容量	10.04 MJ·(kg·K)^-1
T	气体温度	300 ℃
LCID	充气速率曲线	2
MU	泄气孔形状系数	0.7
PE	环境压力	100 kPa
RO	环境密度	1.20 mg·m^-3

关键字	含义	参数值
VSCA	体积缩放系数	1
PSCA	压力缩放系数	1
VINI	初始体积	0
MWD	质量阻尼系数	0
SPSF	滞点压力系数	0
CV	定容热容量	1.700 MJ·(kg·K)^-1
CP	定压热容量	10.04 MJ·(kg·K)^-1
T	气体温度	300 ℃
LCID	充气速率曲线	2
MU	泄气孔形状系数	0.7
PE	环境压力	100 kPa
RO	环境密度	1.20 mg·m^-3