کنترل تطبیقی آموزش تکراری از ردیابی مسیر غیریکنواخت برای بازخورد دقیق سیستم های تغییرات زمانی غیرخطی با جهت کنترل ناشناخته

The iterative learning control problem of strict feedback nonlinear system with unknown time-varying parameters and uncertain control direction is an open problem. An iterative learning control strategy is presented for a class of nonlinear time-varying systems with unknown control direction to solve the non-uniform trajectory tracking problem. Backstepping design technique is applied to deal with system dynamics with non-global Lipschitz nonlinearities. Based on the Lyapunov-like synthesis, we show that all signals in the closed-loop system remain bounded over a pre-specified time interval [0,T][0,T], and complete non-uniform trajectory tracking of the system output is achieved. The time-varying parameters are expanded into Fourier series with bounded remained term. A typical series is introduced in order to deal with the unknown bound of remained term and the non-uniform trajectory tracking. Nussbaum function is used to deal with unknown control direction. Finally, a simulation example shows the feasibility and effectiveness of the approach.