Biomimetic seal whisker sensors for high-sensitivity wake detection and localization

Area of Science:

• Biomimetics and Sensor Technology
• Hydrodynamics and Fluid Mechanics
• Robotics and Underwater Systems

Background:

• Pinnipeds possess highly sensitive whiskers capable of detecting minute hydrodynamic disturbances for navigation and prey detection.
• Existing engineering solutions lack the passive flow perception capabilities found in biological systems.
• There is a need for cost-effective, biomimetic sensors for underwater spatial flow perception.

Purpose of the Study:

• To design and fabricate a low-cost, whisker-inspired sensor array for underwater sensing and tracking.
• To replicate the hydrodynamic disturbance detection capabilities of pinniped whiskers.
• To demonstrate the feasibility of artificial whisker sensors for passive flow perception.

Main Methods:

• Integration of metal foil strain gages within a polydimethylsiloxane soft base.
• Development of a 3D-printed biomimetic seal whisker model.
• Testing sensor performance, including sensitivity, linearity, repeatability, and dynamic response.
• Deployment of a nine-sensor array with an artificial neural network for source localization.

Main Results:

• The sensor exhibits low self-noise and high sensitivity, detecting flow speeds as low as 0.5 mm s⁻¹.
• Dual strain gages enable precise measurement of whisker bending amplitude and direction.
• The sensor demonstrates excellent linearity, repeatability, fatigue life, and low-frequency dynamic performance.
• A nine-sensor array successfully predicted dipole source locations using an artificial neural network.

Conclusions:

• Whisker-inspired sensors offer a feasible solution for robust underwater spatial flow perception.
• The developed sensor technology is cost-effective, easy to fabricate, and suitable for large-scale array deployment.
• This biomimetic approach advances passive flow perception for underwater sensing and tracking applications.