Research On Design Methods And Application For Pedestrian Impact Safety Of Crossover Vehicle

With continuously increasing of CrossOver Vehicle (COV) in China, the scholars and carmanufacturers paid more attention to the pedestrian injury caused by COVs. All the time thescholars and car manufacturers at home and abroad have mainly focused on the research ofpedestrian safety of traditional sedan, and the study of COV's pedestrian protection wascomparatively less. How to reduce the pedestrian injury caused by COV has become anurgent problem in the field of automotive safety, which required in-depth and meticulousresearch on the design theory and technology. This paper is based on the performancedevelopment of pedestrian protection about the self-owned brand COV, by theoretical analysisand computer aided simulation analysis and the real vehicle test, not only providing structuredesign solutions of pedestrian protection for self-owned brand COV, but also exploring themethods and ideas of performance development of pedestrian protection for this type ofvehicles.By establishing the multi-rigid-body impact models of COV and traditional sedan withthe pedestrians, the differences of the pedestrian dynamic response with the two kinds ofvehicles were obtained. And it was identified that the distinct vehicle front structure size andlayout was the main reason for this difference. It provided a theoretical basis for thepedestrian protection performance design of COV's front structure.The pedestrian protection test of a sedan which had the same platform with COV wascarried out and the disadvantages of the sedan in pedestrian protection was analyzed andsummarized, which brought out the design methods of COV. In head impact design method,head collapse space was used to guide the parts layout and design, and a constant idealsquare-wave deceleration curve was constructed to predict the minimum collapse space of thehead impact, which fitted the actual impact deceleration curve. In the leg impact designmethod, an integrated leg impact protection structure was proposed, and the validity of thestructure was verified through simulation analysis.The finite element models of the subsystem impactors were established and verifiedaccording to the regulations and the pedestrian protection design methods proposed in thispaper were applied to the development of self-owned brand COV. The analysis models of vehicle-subsystem impactor were established, and the pedestrian protection performance ofCOV was analyzed in the different development stage, of which results show that by theapplication of proposed pedestrian protection design and optimization of the structure, thetarget vehicle finally meet the requirements of the regulations and get a better front structuredesign through optimization analysis.The COV prototype was made according to the final front structure design and thepedestrian protection test was carried out. The test results showed that all the injury values ofhead and leg were under upper limit of the regulations. The test and simulation verificationresults showed that the test results were in good correlation with simulation results, whichalso proved that the pedestrian protection analysis of the COV model was stable and reliable.Finally, the simulation and test results of COV's pedestrian protection performance revealedthe target COV could meet the requirements of GB/T24550-2009(The protection of motorvehicle for pedestrians in the event of a collision).