Research On Occupant Injury Analysis And Reliability Optimization Combining AEB And Active Safety Belt

With the increasing number of vehicles and frequent traffic accidents,the safety performance of vehicles has been widely concerned.The active safety devices represented by automatic emergency braking(AEB)and the passive safety devices represented by occupant restraint system can provide good protection for passengers.However,when the vehicle can’t avoid the collision,AEB will cause the change of occupant posture,which will affect the protection efficiency of the restraint system.In order to effectively limit the movement of the occupant,active safety belt emerges as the times require.Under this background,In order to improve the safety performance of the occupant restraint system,the analysis of occupant collision injury and reliability optimization of the restraint system combining AEB and active safety belt are studied in this paper,the main research works are as follows:Firstly,the simulation model of frontal collision restraint system of a certain vehicle is established.Based on the results of sled braking test and real vehicle collision test,the out of position response of the occupant during AEB phase and the posture and injury response during collision phase are verified.Through the single factor analysis of the key parameters of the active safety belt,the initial values and ranges of the design variables in the optimization research are determined.Then,the injury responses of different percentile dummies under three different cases are analyzed.The results show that occupant’s out of position caused by AEB will aggravate the collision injury at the same collision speed,and triggering active safety belt during AEB phase can effectively correct the out of position and reduce the occupant injury.In order to improve the prediction accuracy of Kriging(KRG)surrogate model,the grey wolf optimization(GWO)algorithm with stronger global optimization ability is used to optimize the correlation parameters of KRG model,then,the GWO-KRG surrogate model is applied to the deterministic and reliability optimization of occupant restraint system.By optimizing the parameters of the KRG model,the GWO-KRG surrogate model is constructed to meet the prediction accuracy requirements.In order to further improve the safety performance of the restraint system and realize the optimal matching between the active pretension parameters and other restraint system parameters,In this paper,combined with the design of experiments method,GWO-KRG surrogate model and multi-Island genetic algorithm(MIGA),the deterministic optimization of the occupant restraint system is carried out,and the safety performance of the restraint system is improved,based on the results of reliability analysis of deterministic optimization,the reliability optimization of restraint system is studied.Through the optimization,the weighted injury criterion(WIC)of the dummy is significantly reduced,the safety performance of the occupant restraint system is improved,and the reliability of the system is also guaranteed.