Semi-Global Finite-Time Observers for a Class of Non-Lipschitz Systems
Nonlinear Control Systems, Volume # | Part#
Shen, Yanjun; Xia, Xiaohua
Digital Object Identifier (DOI)
Observability and Observer Design; Lyapunov Stability Methods
In this paper, we extend the semi-global ﬁnite-time observers design to a broader class of single-output systems that are uniformly observable and possibly non-Lipschitz. The class of systems are characterized by the non-Lipschitz type of conditions with mixed (greater than 1 or less than 1) and varying rational powers of the increments. They include thus as a proper subset of the class of nonlinear systems that were found to admit global asymptotic observers. Finite-time observers can realize the accurate reconstruction of the states in a ﬁnite interval of time. This is achieved with a new local ﬁnite-time stability result and a gain updated law which is better ﬁtted to the property of the nonlinearities.
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