Robust Event-Triggered Control Subject to External Disturbance

This paper studies the event-triggered control problem for systems subject to both dynamic uncertainties and external disturbances. To overcome infinitely fast sampling caused by the disturbance, a new event-triggering mechanism is proposed, which uses not only the measurable system state but also an estimate of the unmeasurable state and the external disturbance. The inter-sampling intervals can be proved to be lower bounded by a positive constant, which is independent on the magnitudes of the unmeasurable state and the external disturbance. With the proposed design, the closed-loop event-triggered system can be input-to-state stabilized with the external disturbance as the input. Refined tools of input-to-state stability (ISS) and the small-gain theorem are employed in solving the problem.