Lightweight design of the thrust rod spherical core based on response surface method and genetic algorithm

To reduce the weight of the thrust rod ball hinge in commercial vehicles while maintaining its original fatigue life, a multi-objective optimization method combining response surface models and genetic algorithms was proposed. Initially, a finite element model of the ball hinge for the commercial vehicle thrust rod was established. Lightweight regions were identified based on finite element simulation results, and two cylindrical cavities were incorporated to hollow out the spherical core. Secondly, the center coincidence surface design method was employed to select test points within the optimized space. A response surface model was developed for core stress and weight. Finally, the genetic algorithm calculation program was written in MATLAB, and the Pareto optimal solution was obtained through solution. Comparison of simulation results before and after optimization revealed 24.36% in spherical core weight, with no significant change in stress. Moreover, the safety margin remains substantial compared to 40Cr material, validating the effectiveness of the optimization approach.