Simulation And Optimization Of Passenger Side Restraint System In Frontal Crash Based On C-NCAP

With the rapid development of economy,as of 2020 the number of motor vehicles in China has reached 372 million,including 280 million cars.While cars are convenient for people to travel,traffic accidents are more and more common.More than 1.35 million people dead in traffic accidents worldwide each year,making road traffic injuries the eighth leading cause of death.Passive safety technology,which is used to protect passenger safety,has gradually been paid more and more attention by more countries and automobile companies.In recent years,the casualty rate of the front passenger side in the traffic accident is gradually rising,and even has exceeded the driver’s casualty rate.In this paper,based on the latest version of China New Car Assessment Programme(C-NCAP),combined with real vehicle crash test and simulation test,the simulation analysis and parameters optimization of the front-row passenger side restraint system model are carried out by using optimization algorithm.The project is supported by the National Natural Science Foundation of China(51675257),the aim is to deepen the research on the passenger restraint system and improve the protection effect of the restraint system to the passenger.The specific research contents and methods of this paper are as follows:(1)Establishment of simulation model of front-row passenger side restraint system.The three-dimensional model of the front passenger airbag(PAB)was established by CATIA software.ANSA software was used to build the grid model of the front passenger airbag.MADYMO software was used to build the simulation model of multi-rigid passenger side restraint system.The simulation models of constraint system include vehicle multi-rigid body model,safety belt model,Hybrid III 50 percentile male dummy model,seat model,PAB model,relevant contact and constraints.The visualization module in MADYMO software is used to animate the constraint system simulation model.(2)Verification of constraint system model and real vehicle test.A frontal 100% overlap collision simulation test was carried out on the simulation model of the passenger side restraint system,and the mechanical characteristic curves of each part of the dummy were obtained.At the same time,the frontal 100% overlap crash test of the real vehicle was carried out,and the mechanical characteristic curves of each part of the dummy after the test were directly obtained according to the data collector.By comparing the mechanical characteristic curves of the simulation model and the real vehicle collision,the individual fitting degree and the overall fitting degree of each part of the dummy curve were calculated.(3)Parameters optimization of constraint system.Through the sensitivity analysis method,we can get the parameters which have obvious influence on the constraint system model.Latin hypercube test was used to take uniform value and reasonable combination in the optimization parameters.GA genetic algorithm was used to optimize the parameters combination,and the overall complete damage index WIC was taken as the objective function to evaluate the fitness of the parameters combination and optimal parameters combination.The sled test and real vehicle test were carried out on the constraint system with a frontal 100% overlap of 50km/h and a bias of 8°.The curves generated were compared with those generated by the simulation model and the fitting degree was evaluated to verify the effectiveness of the optimal parameters combination again.