Adaptive Fuzzy Cooperative Control Based on a Predefined Time Disturbance Observer for MASs

External disturbances can render constrained multiagent systems (MASs) unstable and affect their convergence speed. To address this issue, the cooperative control strategy for MASs based on a predefined time (PT) disturbance observer (PTDOB) is proposed in this article. First, the original time-varying constrained states of MASs, which are influenced by external disturbances and have a coupled communication topology, are transformed into unconstrained states using the nonlinear transformed function (NTF). This transformation ensures that the limitations of various physical states for agents are not exceeded. Second, the transformed unconstrained states are used to construct the PTDOB for fast observation of external disturbances. Then, based on the proposed PTDOB and the backstepping control technique, an adaptive fuzzy PT cooperative controller is designed. This controller not only ensures the convergence of MASs within PT but also prevents the states from exceeding the time-varying bounds. Finally, the effectiveness of the proposed control strategy is demonstrated through its application to multiple single-link robotic arms as illustrative examples.