Kybernetika 51 no. 1, 36-58, 2015

Transformation of nonlinear state equations into the observer form: Necessary and sufficient conditions in terms of one-forms

Vadim Kaparin and Ülle KottaDOI: 10.14736/kyb-2015-1-0036


Necessary and sufficient conditions are given for the existence of state and output transformations, that bring single-input single-output nonlinear state equations into the observer form. The conditions are formulated in terms of differential one-forms, associated with an input-output equation of the system. An algorithm for transformation of the state equations into the observer form is presented and illustrated by an example.


nonlinear control system, state and output transformations, observer form, differential one-form


93C10, 93B10, 93B17


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