Abstract:

In order to understand the application risk of the pedestrian ground collision injury protection method based on braking control under the disturbance of the first time for releasing the braking （t₁）， 1 920 simulation tests are designed and conducted by MADYMO based on a virtual simulation system with 3 velocities， 4 pedestrian sizes and 2 pedestrian gaits. After comparison analysis， it is found that the pedestrian-ground collision injury can be effectively reduced without increasing the vehicle induced injury by employing the vehicle braking control method when there is no parameter disturbance. Under the disturbance of the first time for the vehicle to release its braking （t₁）， the proportion of cases in which the WIC is reduced， the vehicle related HIC₁₅ is not changed， the ground related HIC₁₅ is reduced and the pedestrian landing posture is not changed is 86.1%、98.61%、90.16% and 90.97% respectively. This means that the vehicle braking control method has a strong anti-disturbance ability. The earlier of t₁， the more likely it is to increase the vehicle induced injury； the later of t₁， the more likely it is to reduce the protective effect of head ground collision injury. Further analysis shows that main reasons for the increase of the pedestrian-ground collision injury under t₁ disturbance are long time no leaving of the pedestrian from the vehicle， the pedestrian falling to the ground from the edge of the vehicle， change of the pedestrian landing posture and already extremely low injury in the complete braking group， etc. Parameters such as bumper length and hood inclination angle significantly affect the anti-disturbance ability of the vehicle braking control method. The smaller the bumper length and the larger the inclination angle of the hood， the stronger the anti-disturbance ability of the method.

Key words: pedestrian-ground collision injury, vehicle braking control, the first time for releasing the braking, disturbance, risk