Research On The Improving Of The Vehicle Bumper Based On Pedestrian Lower Leg Protection

In the recent years, with the rapid increase of traffic accidents, pedestrian protection had gradually become the focus of Automotive Passive Safety. In the traffic accident, the lower leg of pedestrian was easily suffered from injuries, and the injuries were mainly caused by the strike of front bumper, so the research of the bumper was very important for improving the pedestrian protection capability.The lower leg protection capability of vehicle bumper was researched by computer simulation. Firstly, what causing the injuries of the pedestrian leg in the traffic accident was analyzed from the degree of Biomechanics. According to the criteria of EEVC pedestrian protection, the finite element model of the lower legform was established, the model was tested by computer simulation of the static bending test, static shearing test and dynamic impacting test, and the Bio-mechanical behaviors of model had satisfied the criteria.Secondly, based on the finite element model of the lower legform, simple model replacing automotive front structure was established. It was analyzed by Orthogonal Experiment that maximum knee bending and shearing deformation, and tibial peak acceleration were how to influenced by the height, width, protrusion amount of bumper, the height of bonnet leading edge, etc. Moreover, the trends and differences of the influence were obtained, they would provide reference for the vehicle design.Finally, the bumper of a car was as the researched object in this paper, for the pedestrian protection performance of the bumper, some improvement measures were proposed. It was researched that the injuries of pedestrian lower leg were how to influenced by the material mechanical parameters of vehicle skin, the structure and material of energy-absorbing block. In order to adjust the state of lower leg motion in the collision accident, a new auxiliary bumper was added to the system. Meanwhile, the original bumper was improved comprehensively, and the rationality and feasibility of improvement measures were confirmed by computer simulation, then, the energy-absorbing performance of the bumper was improved, the injuries of pedestrian lower leg were reduced greatly.