In order to reduce tire wear and improve braking nose dive performance, a selection strategy of multiple design variables is proposed based on the grey correlation TOPSIS method. The simulation model of front suspension and steering system is established by using multi-body dynamics simulation software and its K&C characteristics are analyzed, with its accuracy verified by experiments. With the target of improvement of tire wear and braking nose dive performance, based on the sensitivity analysis of 15 hard point coordinates of the front suspension and steering system, the weight of each index is determined by entropy weight method and subjective weight method, and 6 hard point coordinates with high comprehensive contribution coefficient are selected as design variables by combining the grey correlation degree and TOPSIS method, so as to construct the optimization design model. By using Isight software and NSGA-II algorithm, the Pareto optimal solution set is obtained and the optimal scheme of hard point arrangement of the suspension and steering system is finally determined. After optimization, the performance is improved significantly compared with the initial design, with the change rate of toe angle, camber angle, lateral and longitudinal displacement with wheel slip reduced by 48.9%, 21.2%, 26.6% and 20.5% respectively, the Ackerman percentage increased by 19.02%, the anti-dive rate increased from 9.2% to 30.4%, and the height of roll center reduced from 136 to 100.5 mm, effectively reducing tire wear and improving braking nose dive performance while ensuring operation stability. © 2020, Society of Automotive Engineers of China. All right reserved.
