Integrated Guidance and Control Using Prescribed Performance Fractional-order Sliding Mode for Rendezvous of AUV and USV

This paper proposes a performance-guaranteed fractional-order sliding mode integrated guidance and control (IGC) method for rendezvous of AUV and USV with random disturbances. The strategy of rendezvous AUV and USV includes: a fixed-time convergence sliding mode disturbance observer is designed to estimate the random impulsive disturbance of AUV and USV, and a fractional-order sliding mode IGC is proposed by constructing a fractional-order mode surface and designing a prescribed performance index to ensure control performance. The closed-loop stability of the controller is proved and the control and guidance are integrated to ensure that the tracking error is within the specified performance constraint range in the transformed coordinate system, which means that the performance function can ensure the steady-state error, the convergence speed and reducing the overshoot. The effectiveness and robustness of the controller are verified by numerical simulation.