Adaptive Robust State Observers of Uncertain Dynamical Systems with Time-Varying Delays

Hansheng Wu

Department of Information Science, Prefectural University of Hiroshima Hiroshima City, Hiroshima 734-8558, Japan.

DOI: 10.4236/ojapps.2012.24B039                

Abstract

The problem of adaptive robust state observer design is considered for a class of uncertain dynamical systems with Time-varying delays. A new method is presented whereby a class of memoryless adaptive robust state observers with simpler structure is proposed. It is also shown that by employing the proposed adaptive robust state observer, the observation error between the observer state estimate and the true state can be guaranteed to be uniformly exponentially convergent towards a ball which can be as small as desired. Finally, a numerical example is given to demonstrate the validity of the results.

Keywords

Adaptive control; robust control; time-delay systems; state observer; convergence

Conflicts of Interest

The authors declare no conflicts of interest.

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