Global output tracking for a class of single-input single-output non-linear systems

The problem of the global output tracking is considered for a class of single-input single-output systems. The class of non-linear systems considered here is constituted by the systems linearizable via state feedback, while the class of reference signals to be asymptotically tracked is constituted by the reference outputs generated by an external system: the exosystem. A procedure for the design of a compensator is proposed, which ensures a global convergence property, under a sufficient condition, which, in case of linear systems and of an exosystem constituted by a cascade connection of some integrators, reduces to the absence of invariant zeros in the origin of the complex plane. No minimum phase requirement is needed to apply the procedure. An example and some simulation runs are given showing the effectiveness of the proposed controller. © 1994 Taylor & Francis Group, LLC.