Wake Detection and Positioning for Autonomous Underwater Vehicles Based on Cilium-Inspired Wake Sensor

Area of Science:

• Marine robotics
• Underwater sensing technologies
• Fluid dynamics

Background:

• Autonomous Underwater Vehicles (AUVs) are crucial for marine exploration and surveillance.
• Effective detection and tracking of AUVs are essential for mission success and operational safety.
• Passive sensing methods offer advantages in terms of reduced detectability and power consumption.

Purpose of the Study:

• To propose and validate a novel passive detection method for AUV wakes.
• To develop a cilium-inspired wake sensor (CIWS) for underwater flow field detection.
• To establish a technical foundation for AUV detection and tracking using wake signature analysis.

Main Methods:

• Characterization of the cilium-inspired wake sensor (CIWS) and its working principle.
• Measurement of flow velocities in the wake of the "TS MINI" AUV using a flow velocity sensor.
• Establishment of an AUV wake velocity field model.
• In-situ measurement of the AUV wake using the CIWS at various positions.
• Analysis of wake data to identify characteristic propeller frequencies and establish a mapping model between spectral amplitude and wake velocity.

Main Results:

• The characteristic frequency of the AUV propeller was identified and correlated with rotation speed and blade count.
• A mapping model was developed linking spectral amplitude at characteristic frequencies to wake velocity.
• The CIWS successfully measured AUV wake fields.
• The study demonstrated the estimation of sensor position relative to the AUV propeller.

Conclusions:

• The proposed CIWS offers a viable method for passive AUV wake detection.
• The developed models enable the estimation of AUV position based on wake characteristics.
• This research provides a significant advancement for underwater detection and tracking systems.