A note on practically output tracking control of nonlinear systems that may not be linearizable at the origin

Abstract

This paper studies a globally practical output tracking control of nonlinear systems in the strict-feedback form, whose chained integrator part has the power of positive odd rational numbers. Since the power is not restricted to be larger than or equal to one, the linearization of the system at the origin may fail. Nevertheless, it is proved that, under mild assumptions, globally practical output-tracking is achievable by continuous (possibly non differentiable) state feedback. © 2011 Springer-Verlag Berlin Heidelberg.