Predefined-Time Zero-Error Tracking in Cyber–Physical Systems Under DoS Attacks via Event-Triggered Approach

Most existing control strategies for nonlinear systems under Denial-of-Service (DoS) attacks require prior knowledge of the attack frequency and duration, and typically achieve only bounded or asymptotic convergence. In this paper, an adaptive predefined-time (PT) event-triggered security control scheme is developed for a class of nonlinear strict-feedback cyber-physical systems subject to DoS attacks. By designing an adaptive high-gain filter, the discontinuous and unmeasurable states caused by DoS attacks are estimated in a smooth and differentiable manner within a PT. Building on this estimation, the proposed control strategy ensures not only the ultimate boundedness of all closed-loop signals but also guarantees that the tracking error converges to zero within a PT, even when the frequency and duration of DoS attacks are unknown. The key advantages of the proposed approach lie in its broader applicability and improved control performance, while concurrently conserving communication resources. Finally, numerical simulations are provided to demonstrate the efficacy of the proposed method.