VIP-Dock: Vision, Inertia, and Pressure Sensor Fusion for Underwater Docking with Optical Beacon Guidance

Underwater docking enhances the operational capabilities of Autonomous Underwater Vehicles (AUVs) by facilitating energy and data transfer. Optical beacons serve as the primary guidance method for AUVs to localize and track docking stations. This paper presents VIP-Dock, a novel optical beacon tracking algorithm for robust underwater docking of AUVs. VIP-Dock addresses the challenge of maintaining accurate beacon tracking under visual interference by integrating visual, inertial, and pressure perception. Employing an unscented Kalman filter framework, the VIP-Dock algorithm provides continuous optimal estimation of beacon positions. Experimental results demonstrated VIP-Dock's real-time tracking performance in actual docking scenarios and its ability to maintain accuracy during visual input failure. Implementation in a simulation platform for an underwater vertical shuttle showed significant improvement, increasing docking success rates from 62% to 84% across 100 trials under simulated current disturbances.