Secure adaptive output-feedback tracking control for a class of uncertain nonlinear systems in the presence of sensor and actuator faults under DoS and injection attacks

This paper addresses the critical issue of secure and resilient control for a class of uncertain nonlinear systems exposed to sensor and actuator faults and cyber-physical attacks such as Denial of Service (DoS) and injection attacks. We propose a novel secure adaptive output-feedback tracking control (SAOFTC) approach that employs a switching gain observer and a dynamic high gain observer to ensure robust tracking control and cyber resilience. A fault-tolerant, adaptive approach to tracking control addresses the uncertainties inherent in the system as well as sensor and actuator faults. By integrating adaptive control, a fuzzy logic system (FLS), and observer-based techniques, the proposed method dynamically adjusts the control parameters to account for system uncertainties and mitigate the impact of disturbances, sensor and actuator faults, and injection attacks. Our proposed approach ensures system stability and tracking performance and provides robust protection against cyber-attacks. Simulation results on a nonlinear system demonstrate the effectiveness of the proposed methodology and highlight its potential for controlling critical infrastructures and cyber-physical systems (CPSs) where security and resilience are of paramount importance.