Research On Front Protection Of Car Restraint System For Children

With the increase of car ownership year by year,children ride more and more frequently,and children's safety is getting more and more attention.Studies have shown that children's head contact with the front seats is an important cause of serious injuries to child occupants.The current research on child restraint systems mainly focuses on the optimization of the child safety seat's own parameters,and there are few studies on whether the front protection of child restraint systems is perfect.As children travel more and more frequently,the protection effect of the child restraint system is required to be more comprehensive and the protection efficiency is higher.It should be ensured that when children use the child restraint system correctly,they will no longer be harmed by the vehicle's interior.In order to improve children's riding safety and improve the protection effect of the child restraint system,it is of great significance to carry out research on the front protection of the child restraint system.Based on the finite element theory,this paper uses the multi-rigid body dynamics module MADYMO to establish a child restraint system simulation model and a five-point child seat belt.And the model was tested and verified.On this basis,an airbag is established behind the driver's seat.Analyze the protective effect of airbags on children.Finally,the relevant parameters of child safety seats and airbags were selected,and NSGA-? multi-objective genetic algorithm was used to optimize the relevant parameters.Based on the imperfect protection of the front of the child restraint system,the main research contents of this article are as follows:(1)Build a child safety seat model and verify it with a trolley test under an offset collision condition.The length of the seat belt,the coefficient of friction between the seat belt and the dummy,and the coefficient of friction between the child safety seat and the rear seat are analyzed through simulation.Orthogonal experiment design is performed on the parameters within the feasibility range,and the WIC value is compared to determine the effectiveness of child safety belts on child protection.and select the parameters that have a greater impact on child safety are screened for subsequent optimization.(2)An airbag was built under the headrest on the rear side of the driver's seat to analyze the placement of the child airbag,the area of the exhaust hole,and the gas mass flow rate.Orthogonal test design for selected parameters within the feasibility range.Determine the effectiveness of the airbag on child protection by comparing the size of the WIC value,and select the parameters that have a greater impact on child safety for subsequent optimization.(3)When considering the impact of child safety seats and child airbags on children,based on the size of the effect on children,screen out the length of child seat belts,friction factors of child seat belts,airbag installation positions,and airbag exhaust Mouth diameter,airbag gas mass flow rate,five parameters that have a greater impact on the injury of child dummy.To the child's head and chest acceleration acceleration optimization objectives,using NSGA-? multi-objective genetic algorithms to optimize the analysis.This article uses a trolley test to calibrate the correctness of the simulation model.On the basis of determining the correctness of the simulation model,an airbag is added behind the driver's seat.The front protection of the child restraint system can be improved,and the child's head acceleration can be reduced,and the child's chest acceleration fluctuation frequency can be reduced.The research results of this paper have certain reference value for improving children's riding safety.