Research On The Optimization Of Side Airbag For Vehicle Side Impact

At present,there is a serious imbalance between the increasing demand for road traffic and the transportation facilities supply in China,resulting in serious road traffic problems.As one of the precipitating factors of traffic problems,traffic accidents directly affect road traffic safety.Related statistical results show that the probability of vehicle side impact in China ranked second only to front impact,and due to side structure has fewer parts that can absorb energy and it does not have enough room for deformation,the side impact directly damages the human critical organs such as the head,chest and abdomen,so the side impact has the highest death and injury rate.Therefore,how to protect the important parts of the occupant in side impact and improve the safety performance of the vehicle has become an important research topic for the vehicle passive safety.On the basis of analyzing vehicle side impact and considering the influence of side airbag parameters on occupants' safety,side impact sub-structure model is constructed.The validity of the model is verified by side impact test of a domestic vehicle.And the optimization of vehicle side airbag parameters is carried out.The following are the main research contents of this thesis:(1)Vehicle side impact sub-structure model is established.By using the vehicle data of a domestic vehicle and software such as Auto CAD,CATIA and HYPERMESH,vehicle side constraint system sub-structure model is established,including modules such as the vehicle body on the driver's side,seat and side airbag.Multi-rigid body dynamics simulation software MADYMO is adopted to complete collision process simulation.(2)Side impact vehicle test is conducted to verify the sub-structure model.A domestic vehicle is chosen and according to the 2015 version of C-NCAP deformable mobile walls test method,the vehicle test is conducted.The dummy's movement in the process of side impact and the injury of chest and abdomen are obtained.On this basis,related parameters in vehicle side impact model are calibrated,thus the effectiveness is verified.(3)The optimization study of side airbag is conducted.The mass flow rate,the fabric leak ability coefficient and the ignition time are chosen as design variables,and the output of simulation are the Rib Deflection Criterion,the Viscous Criterion,the Abdominal Peak Force and the Pelvis Strain Peak Force.Simulation tests are designed by the application of uniform test method,and the regression analysis of the test data is conducted by adopting response surface method,thus the response surface model between multiple damage assessment value and design variables.The response surface model is optimized by the application of genetic algorithm,and the optimization parameters of airbag are obtained to minimize the multiple damage assessment value.