On the convergence of open-closed-loop D-type Iterative learning control for nonlinear systems

Iterative learning control (ILC) is a simple and effective method for the control of systems that perform same task repetitively. In this paper, open-closed-loop D-type ILC problem is investigated for a class of nonlinear time-varying systems. Under a few reasonable assumptions, sufficient condition for guaranteeing the convergence of the learning scheme is given and then proved with linear operator theory. The condition is independent of the specific form of the state space model, also it is weaker than known results for D-type ILC scheme.