Interval observer design based on nonlinear hybridization and practical stability analysis

In this paper we design an interval observer for nonlinear uncertain continuous‐time dynamical systems, in the unknown‐but‐bounded error framework. We show how to generate two coupled hybrid observers, which yield the best conservative upper and lower component‐wise bounds for the state, provided bounds are available for initial conditions and uncertainties. The interval observer depends on a tuning gain, which is chosen to satisfy the practical stability of a given hybrid dynamical system. An example is studied to emphasize the performance of our method. Copyright © 2010 John Wiley & Sons, Ltd.