基于约束H_∞输出反馈的四轮转向模型跟踪控制

Model Following Control of Active 4WS Vehicle Based on Constrained Output Feedback H_∞ Control

以跟踪参考模型为控制策略,提出一种基于约束H_∞输出反馈控制的四轮转向(4WS)控制新方法.将前馈控制和反馈控制相结合,同时控制前、后轮转角,以实现实际车辆模型对参考模型的期望性能跟踪.兼顾抗干扰能力与执行机构输出饱和,将约束H_∞输出反馈控制应用于反馈控制器的设计.仿真实验表明所设计的4WS车辆系统可以很好地跟踪参考车辆模型,提高了车辆的操纵稳定性.

We propose a new four-wheel-steering（ 4WS） control approach using the strategy of reference-model-following control,whose feedback controller is designed based on constrained output feedback H∞ control. By combining feedforward and feedback controls,the front and rear wheel steering angles are simultaneously controlled in order to follow the desired performance of the reference-vehicle model. Taking anti-interference ability and actuator saturation into consideration,we applied the constrained H∞ output feedback control to the design of the feedback controller. Our simulation experiment results show that the proposed 4WS vehicle can follow the reference vehicle model and improve vehicle handing stability.