Event-triggered control for discrete-time systems with unknown nonlinearities: an interval observer-based approach

This paper is concerned with the interval observer-based control for a class of nonlinear systems with unknown nonlinearities. For the purpose of effectively reducing network congestion and improving resource utilisation, an event-triggered strategy is proposed for the channel between the interval observer and the controller. The designed controller with two gains is nontrivial and adequately utilises the real-time information of both the upper bound and the lower bound of system states. By using the monotonicity theory combined with the Lyapunov stability, some sufficient conditions are developed to ensure the closed-loop system with the given event-triggering scheme is input-to-state stable with the simultaneous presence of external disturbances and unknown nonlinearities. Two controller gain matrices and an observer gain are designed via the solution of a set of matrix inequalities. Finally, a simulation example is given to illustrate the effectiveness of the proposed control scheme.