Fluid-structure interaction of a flexible cantilever cylinder at low Reynolds numbers

Mammals such as rats and seals can sense their surroundings with their whiskers. This work examines the coupled dynamics of a flexible cantilever cylinder in the laminar subcritical Reynolds regime to pinpoint the underlying mechanism of flow-induced vibration in sensory whiskers. We find that when certain conditions are satisfied, the cylinder undergoes sustained oscillations due to the frequency lock-in phenomenon in this Reynolds regime. The knowledge generated through this work helps clarify the role of flow-induced vibrations in sensing via whiskers and has relevance to the development of innovative bio-inspired flow-sensing devices for next-generation robotic vehicles.