Adaptive fuzzy secure consensus control of  strict-feedback MASs under energy-constrained  DoS attacks: A high-order fully actuated system approach

In this paper, an adaptive fuzzy secure consensus control strategy based on a high-order fully actuated (HOFA) system approach is proposed for strict-feedback multi-agent systems (SFMASs) under energy-constrained denial-of-service (DoS) attacks. The multi-agent system (MAS) consists of agents modeled as mixed high-order strict-feedback system with unknown nonlinearity. Further, the communication channels between the agents are attacked by the energy-constrained DoS attackers. To deal with the transmitted data from the leader and neighbors, which are unavailable in the presence of DoS attacks, an observer-based switched filter is proposed to estimate the output of the system, which switches between intervals with and without attacks, ensuring that the estimation error of the filter approaches zero by selecting appropriate parameters. In addition, a high-order adaptive fuzzy back-stepping (HOAFB) strategy is proposed to keep the consensus of the multi-agent system. Unlike the classical first-order state space methods, which require the model to be transformed into the type of first-order system, the fully actuated characteristic is used to design the virtual control signal and the controller directly. Moreover, the adaptive parameters are designed to fit the weights of fuzzy logic systems (FLSs), and the uncertain nonlinear of the strict-feedback system is approximated by FLSs. Finally, a numerical simulation of a single-link robot arm with the elastic revolute joint is provided to demonstrate the effectiveness of the proposed control strategy.