有限时间死区修正迭代学习控制器的设计

Design of iterative learning controllers with finite-time dead-zone modification

中文关键词  迭代学习控制  初始修正吸引子  有限时间死区  格莱姆矩阵

英文关键词  iterative learning control  initial rectified attractors  finite-time dead-zone  Gramian

中文摘要

      在任意初始定位条件下, 讨论具有限时间死区修正的迭代学习控制器设计方法. 针对一类高阶不确定非线性时变系统, 通过将其不确定性项线性参数化表达, 进行迭代学习控制器设计；并考虑不确定项界函数参数化情形下的鲁棒迭代学习控制方法. 通过引入有限时间死区, 设计的控制器可使得所定义的误差函数在有限时间内收敛至零; 进而依据能控格莱姆矩阵构造的初始修正项可使得系统在预先指定的时间区间上实现完全跟踪. 理论分析及数值仿真结果表明, 在保证误差函数始终囿于所设计的有限时间死区内的同时, 闭环系统中所有信号均有界.

英文摘要

      Iterative learning control with finite-time dead-zone modification is presented for a class of higher order nonlinear time-varying systems in the presence of initial condition errors. The Lyapunov-like approach is applied to design the iterative learning controller for dealing with parametric time-varying uncertainties, while a robust method is given to cope with norm-bounded uncertainties. With the introduction of finite-time dead-zone, the developed controllers ensure the specified error function to approach to zero over a pre-specified time-interval. A Gramian-based initial rectifying action is used to realize the complete tracking over another pre-specified time-interval. It is shown in the theoretical analysis and numerical simulation that the system states completely follow the desired trajectories after a pre-specified time, and the error function is always confined to stay within the region defined by the finite-time dead-zone. All the signals in the closed-loop system are proved to be bounded.