Research On The Optimization Of Restraint System For Occupants Of Different Statures

The automobile industry is a pillar industry of the national economy.With the increase of the car ownership,the road traffic accident has become a social problem that threatens the safety of human life and property.At the same time,with the development of society,the proportion of female drivers is increasing.At present,the vehicle passive safety devices are designed based on the 50th percentile male dummy stature,The protection effect of the relatively short female driver is not ideal,Therefore,it is very important to improve the matching and compatibility of the driver’s restraint system by taking into account the constraint system research of the different occupant protection,which is very important to improve the protection effect of the restraint system and reduce the damage of the occupants in the traffic accident.In this paper,the finite element model of the full-width collision is established by computer simulation method.After the operation,the B-pillar acceleration is obtained,and the deformation in the passenger compartment is analyzed,and the obtained acceleration is applied to the MB-FE model of the driver-side passenger cab.The dynamic response and damage of 5th female dummy and 50th male dummy in the process of frontal collision are analyzed.By comparing the dynamic response of the dummy with the damage parameter,the risk of injury of female dummy under the condition of matching system is obtained.In order to improve the protection effect of different occupants,this paper uses Weighed injury criterion(WIC)as the evaluation index.According to the damage of different dummy in the case of frontal collision,the relevant parameters are selected as the design variables.The DACE-Kriging approximation model is designed by using the Latin square experimental method.The correlation between the variables and the evaluation indexes is analyzed.By using the non-dominated Sorting Genetic Algorithm II(NSGA-II),the multi-objective optimization is carried out with the aim of minimizing the damage value of different dummy,and the Pareto optimal frontier is obtained as the optimal scheme.The results show that the finite element model used in this paper is not serious in the driver cabin deformation under the condition of frontal collision,Both the front panel intrusion and the steering wheel beating will not cause damage to the dummy.At the same time,the existing restraint system has poor protection on the 5th dummy,5th dummy’s head and chest acceleration is much higher than the 50th dummy and close to the legal limit,the HIC value is also twice the 50th dummy.According to the correlation analysis,it can be seen that the WIC value is positively correlated with the airbag ignition time,the belt stiffness and the seat belt ribbon pull out,which is negatively correlated with the mass flow rate and the vent hole scaling factor of the airbag,and there is no significant effect on the pressure drop of the steering column.According to the response surface analysis,the damage of 5th and 50th were more sensitive to the ignition time and the mass flow rate of the airbag,the preload and the peak value.Compared with the original design,it can improve the protection effect of the restraint system on the drivers of different sizes by reducing the stiffness of the seat belt and improving the mass flow rate and the air hole scaling coefficient.