Nonlinear Observer Normal Form with Output Injection and Extended Dynamic

This paper presents a new extended output depending nonlinear observer normal form. A sufficient geometrical conditions that guarantee a change of coordinates allowing the transformation of a given nonlinear dynamical system into the proposed observer form are given. Throughout this work, it will be showed that, unlike to the existing observer normal forms, this new form enables to design an observer for the Susceptible, Exposed, Infected, and Recovered (SEIR) model of population under an infectious disease.