Direct adaptive control for nonlinear uncertain systems with exogenous disturbances

A direct adaptive nonlinear control framework for multivariable nonlinear uncertain systems with exogenous disturbances is developed. The adaptive nonlinear controller addresses adaptive stabilization, disturbance rejection, and adaptive tracking. The proposed framework is Lyapunov-based and guarantees partial asymptotic stability of the closed-loop system, that is, asymptotic stability with respect to part of the closed-loop system states associated with the plant. Finally, an illustrative numerical example is provided to demonstrate the efficacy of the proposed approach.