带随机时延的网络控制系统鲁棒滑模观测器

摘要

针对一类具有未知外界干扰的网络控制系统,通过对误差动态系统进行线性变换,将网络时延对观测误差系统的影响转化为满足匹配条件的有界不确定项,根据滑模控制理论,在原闭环系统的反馈回路,提出一种鲁棒滑模观测器的设计方法.基于Lyapunov理论,证明观测误差系统对时延引起的不确定项和外部干扰均具有鲁棒性,并证明所设计的观测器可以保证误差系统渐进收敛到所构造的滑模面,且滑模面误差变量渐进收敛到平衡点.通过对控制律的改进,降低系统抖振.同时将观测器的参数设计问题转化为线性矩阵不等式问题,给出观测器系统参数矩阵的设计方法,并进一步给出优化的求解过程,从而避免过大的观测器输入.通过对一种柔性关节机器臂的网络化系统仿真,验证所提方法的有效性.%By means of the sliding mode control theory, a robust sliding mode observer is proposed for the networked control system with unknown disturbances. The effect of the random time-delay to the observer error system is transformed to the matched uncertainty using the matrix transformation. Based on the Lyapunov theory, the robustness of the observer error system against the effect of the time-delay and the unknown disturbances is proved, and the method to decrease the chattering is also studied preliminarily. Moreover, by transforming the parameter designing problem of the observer to the Linear Matrix Inequalities problem, the designing approach of the observer parameter matrices is given, and furthermore an optimal solving process is presented to avoid the oversized observer input. The simulation on a networked flexible joint robotic arm is performed, and the results illustrate the effectiveness of the proposed method.