Design of Nonlinear Observer by Using Chebyshev Interpolation based on Formal Linearization

This paper discusses a design of nonlinear observer by a formal linearization method using an application of Chebyshev Interpolation in order to facilitate processes for synthesizing a nonlinear observer and to improve the precision of linearization. A dynamic nonlinear system is linearized with respect to a linearization function, and a measurement equation is transformed into an augmented linear one by the formal linearization method which is based on Chebyshev interpolation. To the linearized system, a linear estimation theory is applied and a nonlinear observer is derived. To show effectiveness of the observer design, numerical experiments are illustrated and they indicate that the design shows remarkable performances for nonlinear systems.

Authors:

• Kazuo Komatsu
• Hitoshi Takata

Keywords:

• nonlinear system
• nonlinear observer
• formal linearization
• Chebyshev interpolation.

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