An Optimum Study On The Integrated Airbag System For Vehicle Side Impact

In China, the grade crossing is the major pattern of urban traffic roads. Thus, theoccurrence probability of side impact accident is the highest, and the injury rate isalso the highest. The death rate is only less than that of front impact. There are fewcomponents of the side structure of the car that can absorb the impact energy bydeformation. Meanwhile, with less strength of the side structure comparing to otherparts of the car and small buffer space, there are a greater chance of occupant injuries,and particularly likely to cause the damage of the head, chest and other vital organs.So, side impact research has become an important topic in the passive safety field.The side impact performance of cars has to be improved.This paper aims to research on the side impact performance of a domestic brandcar, and proposed a thorax-pelvis airbag and curtain airbag to improve the occupantsafefy. The occupant protection performance of two kinds of airbags is to be analyzedand optimized.First, a deformable moving barrier was established and verified. With a domesticfull vehicle FE model, by using the finite element modeling method, a side impact FEmodel was developed and verified by by comparing it with the requirements of rulesand test data. According to GB20071-2006standard requirements, side impactsimulation was done. Occupant injuries values were obtained by using the MadymoPSM method combining the Madymo sofftawre, and injuries were analyzed andevaluated according to the standard requirements. Based on anlaysis of the injuries,the paper established the thorax-pelvis airbag and curtain airbag to protect the thorax,pelvis and the head. For thorax-pelvis airbag, two chamber airbag was put forwadafter analysis of the single chamber with which the thrax and pelvis couldn’t be fullyprotected. By using the experimental design (DOE), Kriging surrogate model wasestablished. Combining with the multi-objective genetic algorithm NSGA-II, the twochamber airbag was optimized and relatively better results were obtained. Finally, tominimize side impact injuries and ensure that HIC met C-NCAP requirements, acurtain airbag was developed. The protective effect of the curtain airbag and also theharm that may happened to the out of positon occupant (OOP) were investigatedThe results of this study show that: two chamber thorax-pelvis airbag canprovide much better protection to the occupant than single chamber airbag and the dummy injuries, especially the thorax and pelvis injuries, fully met thehigh-performance limits of the regulations after optimizing the two chamber airbag.Combining the substructure method, uniform design, Kriging surrogate model andgenetic algorithm optimization method can achieve a reliable and good result. Theside curtain airbag greatly reduced the coccupant’s head injury and was verified that itcause relatively not severe injuries according to the regulatory requirements.