Multi-objective optimization design of rear seat for a passenger car based on GARS and NSGA-III

A collaborative multi-objective optimization design is conducted for the rear seat of a passenger car. This study introduces a combined optimization strategy that integrates both the multi-objective optimization problem and multi-criteria decision-making approaches. Firstly, a finite element model of the rear seat luggage compartment crash is established, and its accuracy is validated. Secondly, the thickness and material type of the primary stress components of the backrest framework for the rear seat are considered as design variables. The safety test point displacement, material cost, and weight are defined as the optimization objectives, while regulatory standards are taken as constraints to construct a multi-objective optimization problem. Once more, the Pareto frontier solution sets are achieved by constructing the genetic aggregation response surface surrogate model combined with the non-dominated sorting genetic algorithm-III optimization algorithm through experimental design. Finally, the Pareto frontier solution sets are ranked to determine the best compromise solution using the multi-criteria decision-making method, which involves the optimal combination weight and the technique for order preference by similarity to an ideal solution based on the Kullback-Leibler distance. The safety performance, lightweight, and cost-effectiveness of the optimized rear car seat are improved. Specifically, the displacement of the headrest skeleton and backrest skeleton is reduced by 5.96% and 4.47% respectively, the material cost is decreased by 7.1%, and the weight is reduced by 5.54%.