Adaptive reduced-order dynamic compensation for nonlinear uncertain dynamical systems

A direct adaptive reduced-order dynamic compensation framework for nonlinear uncertain systems is developed. The proposed framework is Lyapunov-based and guarantees global asymptotic stability of the closed-loop system states associated with the plant and compensator dynamics. In the case where the controlled system is in normal form with input-to-state stable internal dynamics, the proposed adaptive controller is constructed without requiring the knowledge of the system dynamics. Three illustrative numerical examples are provided to demonstrate the efficacy of the proposed approach.