Adaptive iterative learning control of non-uniform trajectory tracking for strict feedback nonlinear time-varying systems with unknown control direction

作者：Zhang, Chun-Li^*; Li, Jun-Min

来源：Applied Mathematical Modelling, 2015, 39(10-11): 2942-2950.

DOI：10.1016/j.apm.2014.10.070

• Iterative learning control
• Time-varying systems
• Nussbaum function
• Non-uniform trajectory tracking
• Fourier series expansion
• Backstepping

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. Back-stepping design technique is applied to deal with system dynamics with non-global Lips-chitz 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], 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.

• 出版日期2015-6-1
• 单位西安电子科技大学