The design of observers for nonlinear controlled systems presented in this paperconsists of two stages. In the first stage, the nonlinear controlled system is transformed intoan observability canonical form by mealls of a generalized state transformation, in whichthe control variables (inputs) are parameterized, and then the system is control-free. Inthe second stage, an observer is designed for a control-free system. Form the mathematicalpoint of view the method given in this paper is valid for any observable nonlinear controlled(analytic) system, but from the engineering point of view the design for nonlinear observeris constrained by the choice of input variables. By several examples it is demonstrated how to design the observers practically.

The design of observers for nonlinear controlled systems presented in this paperconsists of two stages. In the first stage, the nonlinear controlled system is transformed intoan observability canonical form by mealls of a generalized state transformation, in whichthe control variables (inputs) are parameterized, and then the system is control-free. Inthe second stage, an observer is designed for a control-free system. Form the mathematicalpoint of view the method given in this paper is valid for any observable nonlinear controlled(analytic) system, but from the engineering point of view the design for nonlinear observeris constrained by the choice of input variables. By several examples it is demonstrated how to design the observers practically.