Modal Analysis And Optimization Design Of Six-way Seat

With the implementation of the national sixth stage motor vehicle emission standards,the whole vehicle factory has put forward higher lightweight design requirements for car seats.Car seat,as an important part of the car,is in direct contact with passengers,which not only provides comfortable riding conditions for passengers,but also ensures the safety of passengers.In the process of driving,the excitation from the uneven road surface is transmitted to the seat through the suspension system.When the modal frequency of the seat is too low,the vibration is transmitted to the back of the seat or ACTS on the human body,affecting the ride comfort.However,there is a problem of low modal frequency in the design of car seats.How to carry out lightweight design while meeting the requirements of safety and improving the modal frequency has become a problem for car seat companies.This paper takes a six-way car seat as the research object,in order to ensure the seat safety as the premise,in order to improve the modal frequency and lightweight effect as the purpose,the multi-objective optimization method is used to optimize the seat structure design.First,seat structure simulation model is established and analyzed by Hyper Mesh software for seat finite element before treatment,the seat is obtained by CAE analysis of three simulation test results,are respectively the seat belt protection test Hybrid type 50% before and after the second,the crash test dummy frame structure modal analysis and validation of the seat frame structure modal simulation model is established,simulation model are verified through modal test,the results show that the seat modal analysis results of CAE model is reliable and seat frame structure modal optimization design.In view of the traditional single agent model in alternative material and the thickness of the matching based on the finite element model,the shortcomings,such as too many sample points computation period,this paper proposes a model based on multiple agents lightweighting design method selected six seat the thickness of the parts and materials as design variables,the minimum quality first order frequency as the goal,to dummy maximum amount back corner as constraint,the optimization model is set up,using particle swarm optimization algorithm for multi-objective optimization.By sequence iteration method for each response between design variables and multiple proxy model fitting,after six iteration optimization,the final optimization results meet the convergence conditions of the seat model of optimized CAE modeling and analysis,validate the feasibility of the optimization in the end,the results show that: compared with model based on Kriging agent optimization,based on a variety of agent model,the method of seat weight loss better,at the same time,computing cycles shorter under various security properties that meet regulatory requirements.In order to ensure that the safety performance meets the requirements of the regulations,the optimized seat weight is reduced by 15% and the first-order modal frequency is increased by 7%.