针对摩擦等非线性干扰因素对光电跟踪伺服系统低速性能的影响,系统设计分为两部分完成.将各种干扰信号等效成控制输入端的等效输入干扰(EID,Equivalent In-put Disturbance),针对系统名义模型搭建滑模干扰观测器,利用系统的状态观测误差推导出系统的等效输入干扰,并采用Lyapunov函数推导出该观测器稳定收敛的条件,通过设计增益矩阵与反馈矩阵,调整观测器跟踪系统状态的收敛速度,最终实现抑制系统跟踪过程中的干扰信号;针对系统的动态部分设计了自适应加速度稳定控制器,进一步补偿了干扰估计的不足问题,保证了系统动态跟踪的精度与稳定性,增强了控制系统的鲁棒自适应能力.仿真和实验结果证明了该方法的有效性.
Based on the influence of nonlinear factors on the low-speed performance of opto-electronic tracking servo systems,the system design was divided into two parts.All disturbance was equivalent to an equivalent input disturbance(EID) existed on the control input channel.A sliding mode disturbance observer(SDOB) was put up to observe the system state for the nominal mode.By using the state observe error to estimate EID and derived the stable convergence conditions of this observer by Lyapunov function.By designing the gain matrix and the feedback matrix,the convergence velocity of the observer was adjusted,and suppression of disturbance was realized.An adaptive acceleration controller was employed in the known dynamic part of the system,which compensates the underestimation of the disturbance further,ensures the accuracy and stability of the dynamic tracking system,and improves the adaptive robustness of the control system.Simulation and experiment results show the effectiveness of the proposed method.