Model reference adaptive control for nonlinear systems with unknown degrees (minimal number of tuning parameters)

Proposes a design method of model reference adaptive control for nonlinear systems with unknown degrees. The present adaptive controller is composed of high gain feedbacks of hierarchical structures derived from "backstepping techniques", and the number of adaptive tuning parameters is 3. It is shown that the resulting control system is uniformly bounded, and that the tracking error converges to an arbitrarily small residual region.