01763090

Component

https://www-nrd.nhtsa.dot.gov/departments/esv/26th/

https://www-esv.nhtsa.dot...edings/26/26ESV-000285.pdf

Recently, safety standards for pedestrian protection in third party evaluation typified by NCAP have been increased, and safety performance of vehicles is improving. Among them, the safety performance of the bonnet hood has been particularly enhanced in terms of injury index represented by HIC from the viewpoint of head protection. However, according to the accident statistics, pedestrian fatalities have remained high, and the causes of death include not only the vehicle injury but also the ground injury. Therefore, it is necessary that pedestrian protection technology includes not only vehicle but also ground. In order to reduce the number of pedestrian fatalities, this research focused on the control of the pedestrian’s behavior after accidents and studied methods that can reduce head injuries caused by various factors. In many pedestrian accidents, the speed difference between the vehicle and the pedestrian is large. The pedestrian is accelerated to the speed of the vehicle due to force input from the vehicle. Therefore, if pedestrians can be gently accelerated, the action is expected to be effective in reducing various injuries. For this purpose, it is important to restrain the pelvis close to the center of gravity at the beginning of a collision. As for the ground, by controlling behavior so that a pedestrian can fall from their leg to the ground, head injury can be greatly reduced. For this purpose, it is important to reduce local input to the legs and suppress the swinging up of the legs. In this research, the effect of early pedestrian pelvis restraint was verified using a pedestrian dummy (POLAR) and modified vehicle model. Head injury was evaluated by using Convolution of Impulse Response for Brain Injury Criterion (CIBIC). For verification, a sedan type vehicle with a small initial input to the pedestrian’s pelvis was used, and the collision speed was limited to 40 km/h. Then, based on the vehicle model, which can change the input part and the load characteristics, the relationship between the behavior of the pedestrian and the injury value was studied. In this research, it was confirmed that the angular velocity of the upper body around the center of gravity is reduced by the early input to the pedestrian pelvis, and it is effective for various injury values of the head. It was also confirmed that the swinging up of the leg can be suppressed by controlling the input to the pedestrian leg. Although collision speed and physique are limited in this research, it is necessary to consider the influence of the difference in physique and speed. Furthermore, it is important to integrate with external sensing technology in order to deploy the pelvis restraint device in front of the vehicle before a collision. In this research, it was confirmed that a pedestrian behavior control device may be effective for reduction of generalized injury by vehicle crush and secondary damage by the ground as one solution for further reduction of the number of pedestrian fatalities.

Paper Number: 19-0285-O

01760206

19-0285

English

9p

2019

26th International Technical Conference on the Enhanced Safety of Vehicles (ESV): Technology: Enabling a Safer Tomorrow

Digital/other

Figures; References; Tables

Crash injuries; Pedestrian safety; Pedestrian vehicle crashes

Highways; Pedestrians and Bicyclists; Safety and Human Factors

TRIS, ATRI, USDOT

Dec 23 2020 4:19PM