Investigation of biological seal whiskers to create artificial whisker sensors for underwater robots

Marine animals employ diverse and fascinating flow sensing phenomena by exploiting the ambient complex fluid mechanics to track prey and escape from predators.

Seals are known for their remarkable long-distance prey-hunting capabilities owing to their whiskers which serve as ultrasensitive flow sensors. For e.g., a seal is able to detect a fish swimming 180m away by following its vortex streets.

While the unprecedented tracking abilities of seals and the role played by seal whiskers in reducing vortex-induced vibrations have been conclusively demonstrated in past, the fundamental mechanisms behind such pinpoint tracking remain unclear.

The geometrically intricate shape of the seal?s whiskers is believed to maximize their signal-to-noise ratio to generate high sensitivity to the tiniest hydrodynamic trails.

In this project, we propose investigations of the seal whisker behaviour, both in live seals and in controlled lab experiments, to shed new light on the fundamental mechanisms that enable the seal to display its excellent prey-tracking behaviour.

In particular, how the seal effectively utilizes the spatial distribution of the whisker array on its muzzle to conduct multipoint flow measurements to track and locate its prey is unknown and of great significance.

We propose to study the morphological, mechanical, and material properties of whiskers to explain the exquisite sensing capabilities of seals, and further use this understanding to develop biomimetic flow sensors for underwater robot navigation.

Miniaturized and self-powered, micro/nano electromechanical systems (MEMS/NEMS) strain and flow sensors will be developed for experimental animal studies, and to develop artificial 3D printed MEMS whisker sensors and muzzles for experimental fluid-structure interaction studies.

An artificial seal muzzle with mechanosensory MEMS whiskers will be applied on underwater robots to create artificial vision and energy-efficient maneuvering through fish-like schooling.