考虑不确定扰动的主动后轮转向动力学控制与试验研究

Dynamic Control and Experimental Study of Active Rear Wheel Steering Considering Uncertain Disturbances

针对在复杂工况及不确定扰动下主动后轮转向系统角度高精度跟踪控制及抗干扰问题,首先采用可调长度电控束角杆的主动后轮转向机构实现主动后轮转向动作,并对该系统建立其非线性动力学模型。然后,基于动力学模型分析设计主动后轮转角改进自抗扰跟踪控制方法,利用扩张状态观测器对外部和内部扰动进行观测并将扰动补偿到控制器中,以实现高精度角度控制和抗干扰能力。最后,通过试验证明,本文中采用的可调长度电控束角杆转向机构以及改进自抗扰跟踪控制方法能在不确定负载扰动下实现较高精度的角度跟踪控制,并与常规PID控制相比,改进自抗扰控制方法具有较强的鲁棒性和抗干扰性。

For the problem of high precision angle tracking control and anti-interference of active rear wheel steering system under complex working conditions and uncertain disturbances,firstly,the active rear wheel steering mechanism with adjustable length electronic beam angle bar is adopted to realize the rear wheel steering action,and the non-linear dynamic model is established for the system.Then,based on the analysis of dynamic model,improved active disturbance rejection control(ADRC)tracking control method for the active rear wheel steering angle is designed.Extended state observer(ESO)is used to observe external and internal disturbances and disturbances are compensated to the controller to achieve high precision angle control and anti-interference ability.Finally,experiments show that the steering mechanism with adjustable length electronic beam angle bar and improved ADRC method can achieve high accuracy angle tracking control under uncertain load disturbances.Compared with the conventional PID control,the improved ADRC control method has strong robustness and anti-interference.