Event-Based State Estimation with Switching Static-Gain Observers

An event-based state estimation problem is considered where the state of a dynamic system is observed from multiple distributed sensors that sporadically transmit their measurements to a remote estimator over a common bus. The common bus allows each sensor to run a copy of the remote estimator and to make the triggering decision based on this estimate: a measurement is transmitted only if its prediction by the estimator deviates by more than a tunable threshold. The event-based estimator is a switching observer that mimics a Luenberger observer with full communication of all measurements. It is proven that the difference between the event-based estimator and its full communication counterpart is bounded. The reduction of average sensor communication rates achieved by using the event-based state estimator for feedback control is demonstrated in experiments on a balancing cube.