Design And Simulation For Automobile Seat Backrest Skeleton Structure With Carbon Fiber Composites

With the increase control of energy conservation and environmental protection in various countries,lightweight design has become a research hotspot in the automotive field.Carbon fiber composites are widely used in automobile lightweight design due to their excellent material properties(low density,high specific strength and designability).In this paper,an automobile seat is taken as the research object,and the integrated design of its backrest skeleton structure was carried out based on carbon fiber composites.The multi-objective optimization design was carried out through a combination of the numerical and experimental methods.At the same time,a multi-response weighted adaptive sampling approach based on hybrid surrogate model was proposed,which effectively improves the efficiency of optimization design.Firstly,the finite element models were established according to the requirements of relevant safety performance regulations.The accuracy of the finite element models was verified by comparing the experiment results with the simulation results.Then,on the basis of steel automobile seat,carbon fiber composite materials were applied to the backrest skeleton structure and integrated design was carried out.It is found that the weight of the carbon fiber composites backrest skeleton was reduced by 1.69 kg(39.12 %)while meeting the relevant safety performance regulations based on the comparison of safety performance test simulation results of carbon fiber composites / steel backrest skeleton automobile seats.According to the most of the current adaptive sampling researches were only applicable to single response problems,and most of the complex engineering optimization problems are multi-response system problems.A multi-response weighted adaptive sampling(MWAS)approach based on the hybrid surrogate model was proposed.The feasibility of the method was verified by numerical examples and engineering cases,which provides a low-cost and high-precision surrogate model for the subsequent multiobjective optimization of automobile seat with carbon fiber composites carbon backrest skeleton structure.Finally,the influence of layer number and layer sequence on the safety performance of carbon fiber composite backrest skeleton automobile seat was studied.The safety performance indicators of the backrest skeleton structure automobile seat with carbon fiber composites were taken as the date basis,the layer sequence optimization of backrest skeleton structure with carbon fiber composites was carried out through a combination of the MWAS approach,hybrid surrogate model and genetic algorithm.According to the comparison result before and after optimization of carbon fiber composite backrest frame automobile seat,the weight of the backrest skeleton structure with carbon fiber composites was reduced by 0.49Kg(18.63%)while the safety performance was improved.It is further verified that the MWAS approach can effectively improve the optimization efficiency.