Nonlinear Luenberger observer design via invariant manifold computation

A framework to extend Luenberger observer to nonlinear systems is proposed. The theory of invariant manifolds plays a central role in the framework. It is shown that the invariant manifolds for observer design are often non-standard ones and this makes their computations challenging. The proposed theory successfully removes the condition imposed on the system to be observed in the previous research in nonlinear Luenberger observer. Numerical examples show that the design methods proposed produce more effective observers compared with linear observers.