Experimental Sled Development And Simulation For Occupantrestraint System

Automobile is an important part in China’s development strategic and a vital foundation for the development of the national economy.With the rapid development of the economy,it has greatly changed the way people travel now.The development of automobiles has made an important contribution to people’s living standard and social progress.However,the following problem,traffic accidents,has increasingly serious impact on the social economy.Although the airbag has played an extremely important role in terms of occupant injury reduction,the number of casualties caused by side impact is still large.The manufacturers hope to strengthen the research of occupant restraint system,but the vehicle side impact is very expensive and has long test cycle,so if side impact test sled has high efficiency,good reproducibility and low price which would get an extensive prospect.In this paper,a side impact test sled produced by a certain manufacturer is taken as the research object.The speed of door deformation intrusion due to side impact and pole side impact is analyzed.A honeycomb is used to accelerate or decelerate the vehicle’s door under specific conditions.A simulation model of the sled system under different working conditions was built.The simulation results under different conditions,which are obtained and analyzed to verify the rationality of the test method for the side impact sled under different working conditions.It is also proved that the test sled can be used as a research platform for occupant restraint system in side impact.The main contents of the thesis are as follows:(1)The test method of side impact sled is introduced.The speed of deformation and intrusion of different parts of the door during side impact is analyzed.The engineering model of side impact test sled based on honeycomb deformation is built.The simulation models of honeycombs used for the acceleration and deceleration of the vehicle door are preliminarily built.The rationality of the honeycomb models is verified by FEA in LS-DYNA,which provides supports for the subsequent simulation analysis.(2)A simulation model of the sled is built to simulate the process of side impact.The speed waveforms of the various parts of the door under different schemes,which are analyzed and compared with the vehicle testing data to confirm simulation model’s validity.The waveform results show that when using the second scheme of honeycomb,the velocity of each part of the door is consistent with the test velocity,and the process of the impact accords with the law of conservation of energy,which verifies the correctness and rationality of the finite element model.(3)The simulation results show that when using the first scheme of honeycomb,the trend of each simulation data is consistent with the trend of the experimental data,and the impact process accords with the law of conservation of energy,which verifies the correctness and rationality of the simulation model of the sled used for side impact.