针对具有力反馈空间遥操作系统的时变大时延和环境模型参数不确定问题,提出一种基于线性矩阵不等式(Linearmatrixinequality,LMI1的鲁棒H∞控制方法。对于回路时延是未知时变的遥操作系统,该方法只需要已知时延的上下界,可以解决环境模型参数不确定问题,并获得良好的位置和力跟踪性能。将主从端的动力学模型转化成相应的状态空间方程,并将其离散化、合并为一个离散状态空间方程;然后根据该系统方程,基于LMI方法设计状态反馈控制器,通过定义Lyapunov函数分析闭环系统的稳定性,并且分别给出在环境模型参数确定和不确定情况下,使得闭环系统渐近稳定且满足给定位置跟踪性能的充分条件;仿真试验结果表明所提出的方法可使得遥操作系统渐进稳定且具有好的位置和力跟踪性能。
A robust H∞ control method based on linear matrix inequality (LMI) is proposed for force feedback space teleoperation systems with large time-varying delays and the uncertainty of the environment model parameters. This method only needs to know the bounds of the delay interval for teleoperation systems with unknown and variable round trip time delays. It also can solve the problem that the parameters of the environment are uncertain and obtain good position and force tracking performances. The master and slave dynamics are respectively transformed to state space equations, and they are incorporated to a uniform form, which is discretized in succession. A state-feedback controller is designed for the whole systems based on LMI method; the stability of the closed-loop system is analyzed by defming a Lyapunov function; and sufficient conditions for the controller are presented which enable the closed-loop system to be asymptotic stability as well as guarantee a prescribed position tracking performance under the cases that the parameters of the environment are certain or uncertain. Simulation results demonstrate that the proposed method enables the teleoperation system not only asymptotic stability, but also taking on good position and force tracking performances.