Reducing the effect of unmodeled dynamics by MRAC control law modification

Abstract Solving a tracking problem does not always give desired results even when the adaptive control methods are used. Some difficulties may occur when the apriori assumptions laid down for the problem solution are not satisfied. One of the serious issues is the existence of unmodeled dynamics in the tracking problem. The proposed solutions are mainly based on robustification of the adaptation law. In this paper we propose to reduce the effect of unmodeled dynamics using the MRAC control law modification so that the standard adaptation law ensures the sufficiently small tracking error.