Extended Nonlinear Observable Canonical Form for Multi-Output

In this paper, we give sufficient conditions which guarantee the existence of a diffeomorphism in an extended state space that allows to transform a multi-output nonlinear dynamical system into a nonlinear normal observable canonical form. In particular, we propose an algorithm that permits to derive such diffeomorphism. The main feature of the canonical form is that it is obtained by allowing a diffeomorphism on the outputs and a dynamic extension. It also allows to design an observer with linear error dynamics for the transformed system.