Study On Optimization Of Restraint System In Oblique Crash Under Car To Car Collision

With the rapid development of the economy and the advancement of industrialization, vehicles have been the traffic tool of ordinary family. As the increase of car ownership, the resulting problems are becoming more and more serious: traffic congestion, air pollution, energy waste, traffic accidents and the personal and property security is been threatened. So the design of vehicle safety is drawing more and more attention of vehicle makers. Frontal impact s are the most common form of traffic accidents, but the current vehi cle safety design is mainly focused on 100% overlap frontal rigid wall impact and 40% overlap offset impact. There is less research on oblique crash which accounts for a large proportion of frontal impacts.To make up the blank of research on oblique crash at home and aboard and offer the design reference of restraint system parameters for oblique crash, the injury sensitive factors of the driver are studied. Furthermore, restraint system parameters are optimized according to these sensitive injury factors. The main content of this dissertation are shown as following:1. The full car finite element model of Toyota Yaris was used to conduct the 30° oblique impact. The models of driving area and occupant restraint system were established and validated.2. The sensitive injury parameters of restraint system to the driver in active car and passive car were confirmed. These parameters were the structure parameters of the car, seat belt parameters, airbag parameters and safety seat parameters. The impact trends of these to the drivers were analyz ed in 30°oblique crash.3. The mode FRONTIER software and Latin Hypercube Sampling method were used to find out the sensitive injury factors of the drivers in active and passive car and to optimize the restraint system parameters. The results of the optimization were certificated.The results show that the driver’s head and chest injuries are sensitive to the locations of D-ring, anchor and buckle in 30°oblique crash. Also, the femur forces are sensitive to the locations of anchor and buckle. For the parameters of restraint system, the driver injuries in the passive car are sensitive to airbag fire time, pretensioner fire time, the airbag holes areas and the mass flow rate of the airbag. For the driver injuries of active car, the airbag volume is also contained besides the parameters referenced above. After the optimization, the injury index WIC of driver of passive car is induced by 33.6% and that of the driver of active car is induced by 7.7. The optimization results make the protecting effect of the restraint system for drivers bot h in active car and in passive car to be the optimization.