ADAPTIVE TRACKING FOR A CLASS OF FEEDBACK LINEARIZABLE SYSTEMS

A state feedback control is presented which achieves asymptotic tracki ng of signals generated by a known exosystem for single-input single-o utput nonlinear systems with unknown parameters entering linearly. The following assumptions are required: the nominal system is feedback li nearizable; the tracking dynamics are not affected by unknown paramete rs; the linear approximation of the zero dynamics has no eigenvalue wi th zero real part; pure feedback conditions are satisfied on the vecto r fields multiplying unknown parameters. This extends to a class of no nlinear uncertain systems the regulator theory in [8] and provides ada ptive tracking for systems which may have unbounded tracking dynamics and were excluded in [10].