Hybrid dead-beat observers for a class of nonlinear systems

This paper studies the reduced-order or full-order, dead-beat observer problem for a class of nonlinear systems, linear in the unmeasured states. A novel hybrid observer design strategy is proposed, with the help of the notion of strong observability in finite time. The proposed methodology is applied to a batch reactor, for which a hybrid dead-beat observer is obtained in the absence of the precise measurements of the concentration variables. Moreover, the observer is used for the estimation of the frequency of a sinusoidal signal. The results show that accurate estimations can be provided even if the signal is corrupted by high frequency noise.