Adaptive predefined-time control of PMSM drive system for suppressing hose whipping in aerial refueling

Hose whipping during the docking phase of aerial refueling poses a significant threat to operational safety. To address this challenge via precise and rapid hose length regulation, an adaptive predefined-time control (APTC) scheme is proposed for the permanent magnet synchronous motor (PMSM) drive system of the hose reel mechanism. A radial basis function neural network (RBFNN) is utilized to approximate and compensate for lumped uncertainties and unmodeled dynamics. Furthermore, a novel predefined-time command filter is developed to estimate the derivatives of virtual inputs and resolve the control singularity issue. Building upon these components, the predefined-time controllers and parameter adaptive laws are systematically synthesized via the backstepping framework. Rigorous theoretical analysis guarantees that the PMSM rotor position tracks the desired trajectory within a predefined time, and all signals in the closed-loop system remain uniformly ultimately bounded. Comprehensive simulations and hardware-in-the-loop experiments, including comparative analyses with a fixed-time control scheme, demonstrate that the proposed APTC achieves faster convergence and precise hose retraction, effectively suppressing the hose whipping.