A dual-loop iterative learning control for nonlinear systems with hysteresis input uncertainty

In this work, a dual-loop iterative learning control (ILC) scheme is designed for a class of nonlinear systems with hysteresis input uncertainty. The two ILC loops are applied to the nominal part and the hysteresis part respectively, to learn their unknown dynamics. Based on the convergence analysis for each single loop, a composite energy function method is then adopted to prove the learning convergence of the dual-loop system in iteration domain. One illustrative example shows that the proposed dual learning control scheme can work well under hysteresis input uncertainty.