TY  - EJOU
AU  - Ding, Shigan 
AU  - Qin, Zihe 
AU  - Zhang, Feng 
AU  - Zheng, Mao 
AU  - Lin, Bowen 

TI  - From Virtual Anchoring to High-Precision Station-Keeping: A Dynamic Virtual Guide-Point Strategy for Underactuated USVs
T2  - Computers, Materials \& Continua

PY  - 
VL  - 
IS  - 
SN  - 1546-2226

AB  - To address the challenge of precise station-keeping for underactuated unmanned surface vehicles (USVs) in unknown current environments, our team previously proposed a solution based on a “virtual anchoring” method. However, field tests revealed that the inherent “virtual anchor line” constraint limits positioning accuracy. This work introduces a novel control strategy to overcome the aforementioned issue, which enables accurate unmanned surface vehicle (USV) station-keeping by significantly reducing the distance constraint inherent to traditional virtual anchoring. The core innovation lies in a Dynamic Virtual Guide-Point, whose position is updated based on a real-time estimate of the current direction. The current direction is approximated in real time using a discrete low-pass filter, which provides smooth tracking of the instantaneous flow-direction observation. Subsequently, a controller is designed based on Lyapunov theory to drive the USVs to track this dynamic point. Numerical simulations demonstrate that, compared to the conventional virtual anchoring method, the proposed approach achieves effective hovering at the target with a substantial reduction in positional error. The controller also exhibits strong robustness against variations in current and external disturbances. The proposed Dynamic Virtual Guide-Point (DVP)-based strategy effectively mitigates the limitations of the original method, enabling true “point-keeping” rather than “arc-keeping”, thereby enhancing the USV’s capability to perform precise maritime operations.
KW  - Unmanned surface vehicle; station-keeping; underactuated system; adaptive control; current estimation

DO  - 10.32604/cmc.2026.086097