A Low-Cost Electromagnetic Docking Guidance System for Micro Autonomous Underwater Vehicles

Area of Science:

• Marine robotics
• Ocean observation technology

Background:

• Autonomous underwater vehicles (AUVs) are vital for smart ocean observations, requiring efficient large-scale data collection.
• Long-term AUV missions necessitate reliable power recharge and data transmission, making docking capabilities essential.
• Existing guidance systems often have limitations in challenging underwater conditions.

Purpose of the Study:

• To design and validate a low-cost electromagnetic docking guidance (EMDG) system for micro AUVs.
• To enable autonomous docking for AUV fleets, enhancing spatiotemporal resolution in ocean sampling.
• To provide a robust guidance solution for AUVs, overcoming limitations of optical or acoustic systems.

Main Methods:

• Developed an EMDG system using a transmitter coil on the dock and a three-axial search coil magnetometer receiver on the AUV.
• Optimized the search coil magnetometer for small size and high sensitivity.
• Implemented a signal conditioning and processing subsystem to calculate deflection angles for guidance.

Main Results:

• Successfully demonstrated underwater docking using the EMDG system.
• The system effectively guided AUVs to dock, even in extreme positions.
• The EMDG system proved capable in conditions where optical or acoustic guidance would fail.

Conclusions:

• The developed low-cost EMDG system is effective for micro AUV docking.
• This technology supports the deployment of AUV fleets for enhanced smart ocean observations.
• The inexpensive and compact nature of the search coil sensor allows for broad AUV integration.