A Study On Head-Brain Protections Of Cylists In Vehicle-Bicyle Collisions

Bicyclist was the most vulnerable road users, and frequently involved in vehicle traffic accidences. The proportion of the head-brain injuries in vehicle-bicyclists was next to lower extremity, which often resulted in a fatal consequence. In China the bicyclist safety was still not only a serious social problem, but also an important technical issue to be urgently resolved.This thesis used the integrated method of accident analysis and computer simulation. One aim of it was investigation of traffic accidents and injury epidemiology by using collected vehicle-bicyclist accident data during period of 2001~2006 in Changsha. The accidents were analyzed in terms of the accident distribution, characteristics of human-vehicle-environment, and traffic injury mechanism. The results of the analysis can be used to improve the automobile safety design and develop bicyclist injury protective system. A real vehicle-bicyclist accident in Changsha was reconstructed by using MADYMO multi-body software. In the reconstruction, the kinetic track of vehicle and bicyclist were presented. The main dynamic parameters related to bicyclist 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 bicycle velocity, impact position, vehicle impact velocity vehicle front structures and stiffness on bicyclist 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.Vehicle-bicyclist accident analysis indicates: Side collisions are the most frequent configuration for bicyclist accident. Small passenger car are the main types of accident vehicle. Most serious injuries and fatalities are caused by head injuries. Parametric study indicates: Bicycle velocity and impact position have a great effect on contact position of bicyclist head. To all the researched vehicle types, vehicle velocity and the height of vehicle hood edge have the significant influence on head-brain injuries. To Sedan type, the windscreen is the main contacted position of bicylist's head in accident, the stiffness of Sedan windscreen have the significant influence on head-brain injuries. The research methodology and research result of this study have an significant contribution for vulnerable road users protection and vehicle safety design.