Event-triggered output feedback control for networked control systems using passivity: Triggering condition and limitations

Most of the work on event-triggered control in the literature is based on static state-feedback controllers. In this paper, a dynamic output feedback based event-triggered control scheme is introduced for stabilization of Input Feed-forward Output Feedback Passive (IF-OFP) networked control systems (NCSs), which is a more general case compared with the passive and the OFP systems investigated in our previous work [20]. The triggering condition is derived based on the passivity theorem which allows us to characterize a large class of output feedback stabilizing controllers. We show that under the triggering condition derived in this paper, the control system is finite-gain ℒ₂ stable in the presence of bounded external disturbances. We provide some analysis on the inter-event time which reveals the difficulties of obtaining a common lower bound on the inter-event time when the full-state information of the plant is not used. Some challenges of applying event-triggered control to real time NCSs are also discussed.