Indirect Adaptive Interval Type-3 Fuzzy Tracking Control for Nonlinear Discrete-Time Networked Control Systems With DoS Attacks

This article presents an indirect adaptive interval type-3 (IT3) tracking fuzzy control for a class of unknown nonaffine nonlinear discrete-time networked control systems (NCSs) with denial-of-service (DoS) attacks. To mitigate the adverse effects of attacks, a novel two-mode attack compensator, incorporating an IT3 fuzzy model (IT3FM), is proposed to handle the nonlinear dynamics and uncertainties of NCSs by estimating the unavailable system output during active attacks. Then, an updating algorithm for parameter adjustment, guaranteed to converge via Lyapunov theory, is presented. Subsequently, an indirect IT3 fuzzy controller (IT3FC) is developed to ensure robust tracking performance. Theoretical analysis of the proposed control method shows the boundedness of the tracking error. To mitigate the computational complexity of the proposed control method, we use the same IT3 fuzzy sets for the IT3FM and IT3FC. We also employ a direct defuzzification method within the type-reduction process, bypassing the iterative Karnik-Mendel approach. Eventually, three nonlinear NCSs are given to demonstrate the robustness of the proposed control method.