Global fixed-time prescribed performance control with fixed-time distributed state observer for non-cooperative...

This study addresses the cooperative tracking control problem for multiple unmanned surface vehicles (USVs) tasked with pursuing non-cooperative target in complex marine environments. Initially, a novel fixed-time distributed state observer (FDSO), independent of the system's initial conditions, is developed to estimate state information of the non-cooperative target. Subsequently, a global fixed-time prescribed performance control strategy is proposed by introducing a novel exponential fixed-time shift function (EFSF), effectively eliminating traditional restrictions on error initial conditions inherent. Furthermore, a fixed-time dynamic compensation (FDC) mechanism is originally formulated to mitigate the impact of external disturbances on system performance. Through rigorous Lyapunov stability analysis, the practically fixed-time stability of the closed-loop system is theoretically proven, with theoretical guarantees derived for tracking error convergence to a predefined compact set within fixed time intervals. Extensive simulation results validate the proposed approach in terms of convergence speed, tracking accuracy, and robustness to disturbances.