On Interval Unknown-input Observer Application in Uncertain Metzler Linear System Diagnosis

The objectives of the paper are limitations in design of the interval unknown-input observer, predestined for the uncertain linear Metzler system with disturbances. Expanding the set of linear matrix inequalities warranting the strictly Metzler form of the interval unknown input observer system matrix, the paper presents sufficient condition to establish stable observer of the defined structure. It is shown that this problem can be solved through feasibility of given set of linear matrix inequalities. In contrast with the case of general uncertain linear continuous-time systems, some related properties are deduced to characterize interval unknown input Metzler observers and related residual filters.