Adaptive Output Feedback Control with Prescribed-Time Performance for Nonlinear Cyber–Physical Systems Under Output Constraints, Actuator Backlash, and Malicious Attacks

This paper proposes an adaptive fuzzy prescribed-time output feedback control approach for strict-feedback nonlinear cyber–physical systems (CPSs) subjected to malicious attacks, output constraints, and backlash-like hysteresis. To approximate unknown system nonlinearities, fuzzy logic systems (FLSs) are employed. A practical prescribed-time stability condition is introduced, based on which a prescribed-time output feedback control scheme is constructed using Lyapunov-based analysis and the backstepping technique. The proposed control strategy guarantees that both the tracking error and the observation error converge to small neighborhoods around zero within a prescribed time. Furthermore, all signals within the closed-loop system remain bounded, and the tracking error is driven to a constrained target region near the origin. The effectiveness and robustness of the proposed method are validated through a practical example.