Title: On the use of dynamic saturation and dead-zone in observer design and synchronization problems
14:00 - 15:00
Online (please contact the organizer Bayu Jayawardhana to receive login details)
Speaker: Daniele Astolfi
Title: On the use of dynamic saturation and dead-zone in observer design and synchronization problems
Abstract: We propose a redesign paradigm for stable estimators by introducing a saturation or a dead-zone nonlinearity with adaptive thresholds on the output injection term. Such nonlinearities allow improving the sensitivity to measurement noise in different scenarios (impulsive disturbances or persistent noise such as sensor bias), while preserving the asymptotic convergence properties of the original observer in nominal conditions. These redesigns apply to a broad class of state estimators, including linear observers, observers for input-affine systems, observers for Lipschitz systems, observers based on the circle criterion, high-gain observers, standard and extended Kalman filters. Finally, the same philosophy design is then applied in the context of synchronization problems for a network of nonlinear systems with measurement noise affecting the exchange of information.
Abstract: We propose a redesign paradigm for stable estimators by introducing a saturation or a dead-zone nonlinearity with adaptive thresholds on the output injection term. Such nonlinearities allow improving the sensitivity to measurement noise in different scenarios (impulsive disturbances or persistent noise such as sensor bias), while preserving the asymptotic convergence properties of the original observer in nominal conditions. These redesigns apply to a broad class of state estimators, including linear observers, observers for input-affine systems, observers for Lipschitz systems, observers based on the circle criterion, high-gain observers, standard and extended Kalman filters. Finally, the same philosophy design is then applied in the context of synchronization problems for a network of nonlinear systems with measurement noise affecting the exchange of information.