Effectiveness evaluations and protecting for pedestrian ground contact injury by coupling the airbag and controlling vehicle braking

doi:10.3969/j.issn.1674-8484.2022.03.004

Abstract

Abstract:

A series of simulation experiments were carried out to evaluate the effectiveness of coupling the airbag and controlling vehicle braking in the protection of pedestrian-ground contact injury. In these simulation experiments, there were 4 pedestrian sizes, 2 pedestrian gaits and 3 collision speeds. The simulation selected 4 types of vehicles and an airbag which was equipped at the front of the vehicle, the airbag is as wide as the vehicle. The vehicle was fully braked until the pedestrian head first contact with the car body, so the brake force was reduced to zero and the airbag was fired at the same time; then the vehicle was fully braked again when some criteria were met. The results shown that the method of coupling the airbag and controlling vehicle braking not only simplifies the controlled strategy, but also reduces the Weighted Injury Cost (WIC) of pedestrian-ground contact injury by 91.9% and the mean pedestrian Head Injury Criterion (HIC) by 87.7%. Therefore, a better airbag shape and ignition timing can improve the protection, but other solutions are needed for some pedestrian-ground contact cases.

Key words: automotive safety, pedestrian-ground contact injury, controlled vehicle braking, a virtual test system, airbag, weighted injury cost

CLC Number:

U467.1+4

ZOU Tiefang, ZHAO Yunlong, XIAO Jing, LI Yanchun. Effectiveness evaluations and protecting for pedestrian ground contact injury by coupling the airbag and controlling vehicle braking[J]. Journal of Automotive Safety and Energy, 2022, 13(3): 438-445.

Figures/Tables 12

References 25

[1]	Schachner M, Sinz W, Thomson R, et al. Development and evaluation of potential accident scenarios involving pedestrians and AEB-equipped vehicles to demonstrate the efficiency of an enhanced open-source simulation framework[J]. Accid Anal Prevention, 2020, 148: 1-11.
[2]	周青, 夏勇, 聂冰冰, 等. 汽车碰撞安全与轻量化研发中的若干挑战性课题[J]. 中国公路学报, 2019, 32(7): 1-14. doi: 10.19721/j.cnki.1001-7372.2019.07.001
	ZHOU Qing, XIA Yong, NIE Bingbing, et al. Challenging topics in research of vehicle crash safety and light weighting[J]. Chin J Highway and Transp, 2019, 32(7): 1-14. (in Chinese)
[3]	周青. 提升自动驾驶汽车安全性任重道远[J]. 智能网联汽车, 2020(3): 48-50.
	ZHOU Qing. It is still a long way to go to improve self-driving car safety[J]. Intelli Con Vehicles, 2020(3): 48-50. (in Chinese)
[4]	林国庆, 逯超, 韩龙飞, 等. 汽车自动紧急制动系统行人测试与评价方法[J]. 汽车安全与节能学报, 2020, 11(3): 296-304.
	LIN Guoqing, LU Chao, HAN Longfei, et al. Test and evaluation method of pedestrian automatic emergency braking system[J]. J Auto Safe Energy, 2020, 11(3): 296-304. (in Chinese)
[5]	刘金明, 马华星, 李奎, 等. 行人头部与车辆碰撞中旋转速度对颅脑组织响应影响[J]. 汽车安全与节能学报, 2021, 12(1): 70-78.
	LIU Jinming, MA Huaxing, LI Kui, et al. The influence of rotational speed of pedestrian head-to-vehicle collision on brain tissue response[J]. J Auto Safe Energy, 2021, 12(1): 70-78. (in Chinese)
[6]	王岩. 基于人车事故数据的行人碰撞后运动及损伤规律研究[D]. 北京: 清华大学, 2017.
	WANG Yan. Research on pedestrian’s kinematics and injury pattern after collision based on real pedestrian-vehicle accident Data[D]. Beijing: Tsinghua University, 2017. (in Chinese)
[7]	杨济匡. 汽车与行人碰撞中的损伤生物力学研究概览[J]. 汽车工程学报, 2011, 1(3): 81-93.
	YANG Jikuang. Overview of research on injury biomechanics in car-pedestrian collisions[J]. Chin J Auto Engi, 2011, 1(3): 81-93. (in Chinese)
[8]	Badea-Romero A, Lenard J. Source of head injury for pedestrians and pedal cyclists: Striking vehicle or road?[J]. Accid Anal Prevention, 2013, 50: 1140-1150. doi: 10.1016/j.aap.2012.09.024 URL
[9]	SHI Liangliang, HAN Yong, HUANG Hongwu, et al. Evaluation of injury thresholds for predicting severe head injuries in vulnerable road users resulting from ground impact via detailed accident reconstructions[J]. Biomech Model Mechanobiol, 2020, 19(5): 1845-1863. doi: 10.1007/s10237-020-01312-9 URL
[10]	SHANG Shi, Masson C, Teeling D, et al. Kinematics and dynamics of pedestrian head ground contact: A cadaver study[J]. Safe Sci, 2020, 127. DOI: 10.1016/j.ssci.2020.104684. doi: 10.1016/j.ssci.2020.104684
[11]	SHANG Shi, Otte D, LI Guibing, et al. Detailed assessment of pedestrian ground contact injuries observed from in-depth accident data[J]. Accid Anal Prevention, 2018, 110: 9-17. doi: 10.1016/j.aap.2017.10.011 URL
[12]	ZOU Tiefang, SHANG Shi, Simms C. Potential benefits of controlled vehicle braking to reduce pedestrian ground contact injuries[J]. Accid Anal Prevention, 2019, 129: 94-107. doi: 10.1016/j.aap.2019.05.008 URL
[13]	ZOU Tiefang, LIU Qi, ZHA Aimin, et al. New observations from real-world vehicle-pedestrian collisions in reducing ground related injury by controlling vehicle braking[J]. Int’l J Crashworthiness, 2022, 27(2): 614-631.
[14]	ZOU Tiefang, LIU Zhuzi, WANG Danqi, et al. Methods, upper limit and reason for reducing pedestrian ground contact injury by controlling vehicle braking[J]. Int’l J Crashworthiness, 2021(2): 1-12.
[15]	邹铁方, 刘朱紫, 肖璟, 等. 一种降低人-地撞击损伤的车辆制动控制方法[J]. 汽车工程, 2021, 43(1): 105-112.
	ZOU Tiefang, LIU Zhuzi, XIAO Jing, et al. A vehicle braking control method for reducing pedestrian-ground impact injury[J]. Auto Engi, 2021, 43(1): 105-112. (in Chinese)
[16]	Crocetta G, Piantini S, Pierini M, et al. The influence of vehicle front-end design on pedestrian ground impact[J]. Accid Anal Prevention, 2015, 79: 56-69. doi: 10.1016/j.aap.2015.03.009 URL
[17]	LI Guibing, YANG Jikuang, Simms C. A virtual test system representing the distribution of pedestrian impact configurations for future vehicle front-end optimization[J]. Traf Injury Prev, 2016, 17(5): 515-523.
[18]	Simms C, Wood D. Pedestrian and cyclist impact[M]. Berlin: Springer Netherlands, Solid Mechanics and Its Application, 2009: 248.
[19]	邹铁方, 肖璟, 胡林, 等. 轿车-行人事故中人体损伤来源与相关性分析[J]. 汽车工程, 2017, 39(7): 748-753+747.
	ZOU Tiefang, XIAO Jing, HU Lin, et al. Human-body injury sources and correlation analysis on car-pedestrian accidents[J]. Auto Engi, 2017, 39(7): 748-753+747. (in Chinese)
[20]	LI Guibing, YANG Jikuang, Simms C. Safer passenger car front shapes for pedestrians: a computational approach to reduce overall pedestrian injury risk in realistic impact scenarios[J]. Accid Anal Prevention, 2017, 100: 97-110. doi: 10.1016/j.aap.2017.01.006 URL
[21]	LI Guibing. Optimization of vehicle front shape for pedestrian protection[D]. Trinity College Dublin, 2017.
[22]	Anne Guillaume, Thierry Hermitte. Car or ground: Which causes more pedestrian injuries?[C]// 24th Int’l Tech Conf Enha Safety Vehi, Gothenburg, Sweden, 2015.
[23]	Simms C, Wood D. Pedestrian risk from cars and sport utility vehicles-a comparative analytical study[J]. Proc Inst Mech Engi Part D: J Auto Engi, 2006, 220(8): 1085-1100.
[24]	SHANG Shi, Masson C, Llari M, et al. The predictive capacity of the madymo ellipsoid pedestrian model for pedestrian ground contact kinematics and injury evaluation[J]. Accid Anal Prevention, 2021, 149: 105803. doi: 10.1016/j.aap.2020.105803 URL
[25]	YIN sha, LI Jiani, XU Jun. Exploring the mechanisms of vehicle front-end shape on pedestrian head injuries caused by ground impact[J]. Accid Anal Prevention, 2017, 106: 285-296. doi: 10.1016/j.aap.2017.06.005 URL

车型	WIC / USD		R_WIC/ %
车型	完全制动	控制制动	文14]	文[12]	本文
大轿车	9 834.2	1 193.9	83.9	74.8	87.9
大SUV	15 133.6	1 144.9	88.9	70.7	92.4
小轿车	21 381.4	643.4	97.4	89.5	97.0
小SUV	8 964.9	1 512.7	74.6	62.0	83.1
总和	55 314.1	4 494.9	88.9	-	91.9

车型	WIC / USD		R_WIC/ %
车型	完全制动	控制制动	文14]	文[12]	本文
大轿车	9 834.2	1 193.9	83.9	74.8	87.9
大SUV	15 133.6	1 144.9	88.9	70.7	92.4
小轿车	21 381.4	643.4	97.4	89.5	97.0
小SUV	8 964.9	1 512.7	74.6	62.0	83.1
总和	55 314.1	4 494.9	88.9	-	91.9

车型	HIC		R_HIC / %
车型	完全制动	控制制动	文献[14]	本文
大轿车	350.0	49.6	74.9	85.8
大SUV	401.3	30.5	65.8	92.4
小轿车	479.4	30.3	88.7	93.7
小SUV	333.3	82.7	68.9	75.2
均值	391.0	48.3	75.6	87.7

车型	HIC		R_HIC / %
车型	完全制动	控制制动	文献[14]	本文
大轿车	350.0	49.6	74.9	85.8
大SUV	401.3	30.5	65.8	92.4
小轿车	479.4	30.3	88.7	93.7
小SUV	333.3	82.7	68.9	75.2
均值	391.0	48.3	75.6	87.7