基于降阶观测器的四轮转向车辆随动操纵瞬态稳定性分析

Transient Follow Handling Stability Analysis for Four-wheel Steering Vehicle Based on Reduced Order Observer

对复杂的四轮转向车辆控制系统数学模型进行分析 ,考虑在实际车辆中质心侧偏角等量难以直接测量 ,提出一种基于降阶观测器的四轮转向车辆随动操纵最优控制策略 ,以车辆转向时的质心侧偏角和横摆角速度等为被控制量 ,应用最优控制理论设计反馈控制系统进行高速行驶下的瞬态操纵动态仿真 ,结果表明 ,基于降阶观测器的系统状态向量能很好地跟踪驾驶员发出的操纵指令 。

The complicated model of four-wheel steering vehicle was analyzed, the measurements of the sideslip angle and roll angle of the vehicle were taken into account in reality, and transient follow handling stability of four-wheel steering vehicle based on reduced order observer and optimal control strategy was proposed. The steering yaw rate and sideslip angle in cornering were taken as control target,feedback control system was designed using optimal control theory and dynamic simulation of transient handling stability with high speed was performed. The simulation results show that reduced order observer possesses excellent characteristics of high speed in tracking and the errors are small. So the system has fine dynamic characteristics and can improve maneuverability as well as directional stability and driving safety.