A Study On Head Protection Of Electric Bicycle Riders From Vehicle Collisions With In Depth Accident Analysis

Electric bicycle riders are one group of the vulnerable road users, and they are frequently involved in vehicle traffic accidences. The proportion of the head-brain injuries in vehicle to electric bicycle driver was next to lower extremity, which often resulted in a fatal consequence. In China the traffic safety of the electric bicycle riders is a serious social problem, and also an important technical issue to be urgently resolved.This thesis aimed at study of the injury mechanisms of the head of the electric bicycle riders and the design parameters of vehicle front structures which caused the injuries. Therefore the possible way for improvement of the safety performance of the vehicle front was explored for injury prevention of the rider head. For this purpose, a literature study was carried out for the anatomical structures of human head. The injury patterns and mechanism of head-brain, as well as the main head-brain injury criteria were summarized from the literature study. On site investigation was carried out for in-depth electric bicycle driver accident study. The critical data and investigation methods were summarized in present study. A real vehicle to electric bicycle driver accident in Changsha was reconstructed by using MADYMO multi-body software. In the reconstruction, the kinetic track of vehicle and electric bicycle driver were presented. The main dynamic parameters related to electric bicycle driver injury were calculated. The simulation result compared with real accident, validated the feasibility of simulation methodology and accuracy of muti-body mode. A parametric study was to analyse the influence of vehicle impact velocity and vehicle front structures on electric bicycle driver head-brain injuries .Result of the simulation can be adopted as a basis of establishing safe regulation of vulnerable road users and the vehicle safety design.Parametric study indicates that vehicle impact velocity has remarkable effect on severity of electric bicycle driver brain inury. First of all, vehicle speed has the significant influence to head-brain injuries; it would lead to fatal injuries when the speed exceeds 40 km/h. For the sedan, the brain injury risk of electric bicycle driver can be decreased by properly improving the height of sedan's bonnet leading edge and reducing the bumper height. The methodology and research result from this study has a significant contribution for vulnerable road users'protection and vehicle safety design.