Adaptive robust tracking for nonlinear uncertain systems

The robust tracking design problem for nonlinear uncertain systems is considered in this paper. The nominal system is assumed to be input-output linearizable. The uncertainty is either assumed to be generalized matched or mismatched. The control design combines differential geometric feedback linearization with the deterministic approach, in which no statistical property of the uncertainty is assumed and used; the only assumption on the uncertainty is that it is bounded. The bound of the uncertainty is however unknown. An adaptive scheme is then adopted to track the bound. The adaptive control schemes constructed can be used to replace the previous (nonadaptive) robust tracking controls in practical application