Robust observer-based controller against plant uncertainties

This paper concerns a method of constructing observers for the plant with uncertainties. In a conventional design, the nominal system matrix is chosen as the system matrix of the observer for the system with/without the uncertainties. However, the rationale of this strategy is ambiguous. This paper investigates the degree of freedom in selecting the system matrix of the observer. The observer-structured controllers designed with freedom of the selection are evaluated in the H
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control and estimation performances.