四轮转向汽车后轮转角控制因子控制效果研究

采用汽车的“自行车”模型，建立了四轮转向汽车的数学模型，在MATLAB／Simulink环境下搭建仿真模型，对四轮转向汽车的前轮转角输入控制因子和横摆角速度反馈输入控制因子对汽车操纵稳定性的影响进行了仿真分析．研究表明，两控制因子均能显著降低汽车质心侧偏角和侧向加速度，提高车辆操纵稳定性，但同时又降低了车辆的横摆角速度，降低了驾驶员的转向感觉；横摆角速度反馈输入控制因子对汽车质心侧偏角的影响还表现出了二重性，在四轮转向设计阶段应根据具体情况合理选取两控制因子．

Control Effect Analysis of Control Factors for Rear Wheel Steer Angle of Four-- wheel-- steering-- vehicle

A Four--Wheel--Steering--Vehicle dynamic model with two degrees of freedom is presented in the article, and a dynamic model is built and simulated in MATLAB/Simulink. The control effect of Four--Wheel--Steering--Vehicle rear wheel steer angle control factors--front wheel steer angle control factor and yaw motions feedback control factor-to the vehicle handling stability and the op- erating safety has been simulated and compared. According to the simulation and analysis, it has been proved that the two factors can both decrease the sideslip and the lateral acceleration. However, the vehicle yaw motion has been reduced at the same time, which makes the loss of the driver＇s steering sense. Meanwhile, the control effect to the sideslip of the yaw motions feedback control factor shows duality. It is important and necessary to select the values of the two control factors properly during the vehicle design.