Optimization of vehicle structural parameters considering stability improvement

The main structural parameters that affect vehicle bifurcation characteristics and the safe basin are obtained, with the goal of improving the stability. First, the distribution of the system equilibrium points in three-dimensional space is studied, and the bifurcation characteristics of the front steering angles are obtained. Second, the front steering angle range corresponding to the bifurcation point (FSAR-BP) and the safe basin of the system (SBS) are determined and used as optimization objective functions. Considering the influence of the structural parameters on the FSAR-BP and SBS, a sensitivity analysis of the parameters is performed to establish their importance ranking in terms of their influence on the FSAR-BP and SBS. Third, a non-dominated sorting genetic algorithm II (NSGA-II) is utilized to optimize the parameters, and the competitive Pareto parameter optimization solution sets are obtained. Finally, the three solution sets with better comprehensive performance are selected for comparison with the pre-optimized set in the FSAR-BP and SBS. The results indicate that the optimized FSAR-BP increased by 218.81%, 237.83%, and 267.88%, and the optimized SBS increased by 207.52%, 197.06%, and 173.93%, respectively.