Popis: |
Belt and airbag are the most important protection devices in vehicle frontal crash, which can have the best protective performance when only they were well matched with vehicle body structure. In this paper the theoretical guidance for optimizing belt and airbag parameters is researched, in order to improve the effect and efficiency of parameters optimization of restraint system. Firstly, a simulation model for occupant restraint system is developed based on the finite element theory combined with multi rigid body theory, and its effectiveness for simulating the occupant dynamic response in frontal impact is validated. Then, the energy dissipation characteristics of occupant head and chest in typical frontal crash are analyzed based on the developed model. Lastly, the adaptive level of restraint system parameters are evaluated according to the dissipation characteristics of occupant energy, and theoretical guidance for parameters optimization are summarized based on the evaluation. The analysis results indicate that: (1) airbag with low stiffness cannot fully utilize the deformation of vehicle body to dissipate the energy of occupant head, but may increase the risk of head injury; (2) belt with high stiffness would apply a big force to occupant, which could increase the compression amount of chest and may increase the risk of chest injury. |