Nonlinear Observers and Separation Principle

  • Alberto IsidoriEmail author
Part of the Advanced Textbooks in Control and Signal Processing book series (C&SP)


This chapter considers the design of asymptotic state observers for a single-output nonlinear system. A fundamental property that makes the design of such observers possible is the existence of change of coordinates by means of which the system is brought to a special form in which a property of observability, uniform with respect to the input, is highlighted. For such systems, it is possible to design global asymptotic state observers. Then, a nonlinear equivalent of the so-called separation principle of linear system theory is developed. It is shown how to combine a state feedback stabilizer with a nonlinear observer, so as to obtain a dynamic output feedback by means of which asymptotic stability with guaranteed domain of attraction is obtained.


Nonlinear Observer Dynamic Output Feedback Asymptotic State Observers Guaranteed Domain Canonical Flag 
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Copyright information

© Springer International Publishing Switzerland 2017

Authors and Affiliations

  1. 1.Dipartimento di Ingegneria Informatica, Automatica e GestionaleUniversità degli Studi di Roma “La Sapienza”RomeItaly

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