轮毂电机驱动电动汽车双横臂前悬架运动学优化

基于传统汽车底盘平台进行电动轮驱动改型时,轮毂电机的布置将导致悬架硬点坐标的改变,从而严重影响悬架运动学特性,为此须对电动轮驱动改型车悬架系统进行优化设计。以某传统车底盘平台的双横臂前悬架运动学特性为优化目标,根据参数灵敏度分析结果,提出两步优化方案,即首先进行主销定位参数的优化,而后再进行前轮外倾角和前轮前束角的优化。利用ISIGHT软件和全局非归一化的多目标遗传优化算法NSGA-II得到的悬架参数优化解集在ADAMS/Car平台下进行了验证。结果表明,悬架运动学特性得到较大幅度的改善,特性曲线与原型车悬架K特性实验结果基本一致。证明了该优化方法的可行性,确保了改型后电动汽车的操纵稳定性受安放轮毂电机的影响较小。

Kinematics Optimization of Double Wishbone Front Suspension for In-wheel Motor-Driven Electric Vehicles

In the retrofit of the in-wheel motor-driven electric vehicle based on the chassis platform of traditional vehicle,the placement of hub-motors will result in the coordination change of suspension hard-points,severely affecting the kinematic characteristics of suspension.Therefore,a design optimization of the retrofitted in-wheel motor-driven electric vehicle is required.With the kinematic characteristics of the double wishbone front suspension in a conventional vehicle chassis platform as optimization objectives,a two-step optimization scheme is proposed according to the results of parameter sensibility analysis,i.e.the optimization of kingpin positioning parameters is performed first,then that of camber and toe proceeds.The optimization solution set of suspension parameters obtained by using ISIGHT software and the global non-normalized multi-objective genetic optimization algorithm NSGA-II is validated under the ADAMS/Car platform.The results show that the optimized suspension kinematic characteristics are improved significantly,being basically consistent with the K characteristics of original vehicle,demonstrating the feasibility of optimization scheme adopted and assuring the handling and stability of retrofitted electric vehicle not greatly affected by the placement of hub-motors.