Robust Gain-Scheduling Control for a Class of Uncertain Nonlinear Systems with Exogenous Signals

For the problem of the output regulation of a class of uncertain nonlinear systems with exogenous signals, a new robust gain-scheduling controller is proposed based on variable structure control approach and adaptive estimation for the upper norms of the matching uncertainties in this paper. The controller consists of a nominal nonlinear feedback term designed by the traditional gain-scheduling approach, and a discontinuous modified feedback term derived by the variable structure control approach and the adaptive control method. The considered uncertainties can be decomposed into matching uncertainties and mismatched uncertainties, where the matching uncertainties can be restrained by combining the nominal term with the discontinuous term. Under certain conditions, the obtained closed-loop system provides the desired ultimate output error bounds based on Lyapunov stability theory