Iterative Learning Control Design for Uncertain Dynamic Systems with Delayed States

Abstract. Most available results on iterative learning control address trajectory tracking problem for systems without time delay. The effect of time delay on tracking performance is not yet fully understood. This paper is concerned with iterative learning control design for the systems with delayed states, where the system class under consideration is confined by a defined relative degree. A learning control scheme is proposed to overcome the uncertainties in delay times and=or in system parameters. Robustness of the learning control is established in the presence of initial function errors. Furthermore, uniform convergence of system outputs to the desired trajectory is ensured if the initial function at each cycle is set to align with the desired initial function. Validity of the results is demonstrated through numerical simulations