一种新颖的鲁棒模糊滑模观测器设计及干扰重构方法

A novel robust fuzzy sliding mode observer design and disturbance reconstruction

中文关键词  高增益估计器  鲁棒滑模观测器  线性矩阵不等式  T–S模糊模型

英文关键词  high gain approximator (HGA)  robust sliding mode observer (RSMO)  linear matrix inequalities (LMI)  Takagi-Sugeno (T-S) fuzzy model

中文摘要

      针对一类由T-S模糊模型描述的不确定非线性系统, 提出一种新颖的鲁棒模糊滑模观测器设计和干扰重构方法. 首先, 给出一种T-S模糊模型的等价形式. 其次, 在考虑滑模匹配条件不满足、状态不可测的情况下, 利用高增益估计器构造辅助变量. 为避免其峰化问题, 提出基于高增益估计器的鲁棒滑模观测器. 然后, 基于所提出的等价形式, 给出一类不确定非线性系统的鲁棒模糊滑模观测器设计方法. 并证明其不但对系统的未知干扰具有鲁棒性, 而且能保证状态估计残差在有限的时间内收敛于任意小的邻域, 并可应用等价输出误差介入原理重构出系统的干扰. 最后, 将该方法应用于双关节机械臂的控制仿真实验. 结果表明所提方法的有效性.

英文摘要

      A novel robust fuzzy sliding mode observer design and a disturbance reconstruction method are proposed for a class of uncertain nonlinear systems described by Takagi-Sugeno (T–S) fuzzy model. Firstly, a description which is equivalent to the form of T–S fuzzy model is proposed. Secondly, auxiliary variables are constructed to satisfy the matching condition of sliding mode observer, and a high gain approximator is developed to approximate immeasurable states. To avoid the peak problem occurred to the high gain approximator, we propose a robust sliding mode observer for this high gain approximator. Then, under the equivalent form, a robust fuzzy sliding mode observer is developed for a class of uncertain nonlinear systems. We prove that the proposed observer is robust to unknown disturbances, and ensure state estimation residuals of convergence to an arbitrarily small neighborhood in a limited period of time. At the same time, system disturbance is reconstructed thought the involved principle of equivalent output error. This method has been applied to simulate a two-link robot control system; simulation results demonstrate the validity of the proposed method.