Observer-Based Fuzzy Secure Control for High-Order MASs Against Communication Delays Under Jointly Connected Switching Topology

This research considers the observer-based adaptive fuzzy secure consensus control issue for high-order nonlinear multiagent systems (MASs) against communication delays and deception attacks under jointly connected switching topology. To address the challenges of time-varying communication delays, deception attacks, and leader-state inaccessibility in MASs with jointly connected switching topology, this article develops a distributed consensus observer with delay-attack resilience. The proposed observer simultaneously compensates for time-varying delays and counteracts deception attacks while reconstructing the leader's state information through a consensus observer. To handle system uncertainties with unknown nonlinear functions, a fuzzy logic system (FLS) is employed to approximate the unknown dynamics. A fuzzy state observer is subsequently constructed to reconstruct the unmeasurable states by utilizing accessible post-attack signals and applying adaptive approximation technology. With the help of the backstepping design scheme and the adding power integral method, an observer-based adaptive fuzzy secure consensus control approach is proposed so that the designed communication-delay-attack-related distributed consensus observer errors converge to zero exponentially. Furthermore, the proposed consensus control protocol ensures the stability of high-order MASs while achieving that tracking errors converge in the neighborhood of the origin. The validation through two simulation scenarios demonstrates the protocol's effectiveness.