8×8轮毂电机全轮驱动车辆动力学建模与仿真

Dynamics Modeling and Simulation on Four-Axle Vehicle Driven by In-Wheel Motors

建立了8×8轮毂电机全轮驱动车辆的整车驾驶模型,该模型包括驾驶员输入处理模块、路面条件和22自由度车辆动力学模型,给出了在一定路面条件下,从驾驶员输入到车辆动力学和运动学状态输出的数学方程.采用模块化的方法,在Matlab/Simulink中建立了计算机仿真模型,对所建立的模型进行了操纵稳定性和行驶平顺性的仿真试验,并与常规8×8车辆模型及二自由度线性模型进行了对比分析.仿真结果表明所建立的模型能正确反映车辆在各种工况下的动力学特性,非簧载质量的增加一定程度上降低了车辆的操纵稳定性,尤其降低了车辆的行驶平顺性.

A dynamic model, including the driver inputting module, the road model and the vehicle model with 22 degrees of freedom （DOFs）, was proposed for the four-axle vehicle driven by in-wheel motors. The 22 DOFs, which represented the dynamic characteristics of the vehicle, were consisted of 6 DOFs of the vehicle body and 16 DOFs of the vertical and rotation motion of 8 wheels. Based on the deduced equations, a computer simulation model was established with highly modular approach in Matlab/Simulink software. The simulation tests, including the handling stability and the riding comfort, were performed on the 22 DOFs model and the ideal 2 DOFs linear vehicle model under the same driving condition. The simulation results reveal that the proposed model is able to legitimately describe the dynamic characteristics in various conditions. What＇s more, the dynamic characteristics, especially riding comfort, are deteriorated because of the increased unsprung mass.