On Designing Event-Triggered Output Feedback Tracking Controller for Feedforward Nonlinear Systems

This brief investigates the output feedback tracking control problem for feedforward nonlinear systems subject to event-triggered input. Different from the existing results, it is the first time that an output feedback tracking control algorithm is proposed for feedforward nonlinear systems based on the relative threshold strategy. To estimate the unmeasured states, a novel dynamic observer is designed by using the information of the output and the tracking signal. By the low gain scaling technique, the event-triggered controller is designed based on the observer, which avoids the celebrated forwarding construct approach. Based on the constructed controller and the dynamic low gain, it is proved that all signals of the closed-loop system are globally bounded and the tracking error converges to a prescribed compact set and the Zeno-behavior is avoided. The novelty owes to a distinct perspective in coping with the measurement error such that the linear matrix inequality can be used in the design procedure. The effectiveness of the proposed algorithm is showed by a circuit system.