Propulsion with a Rotating Elastic Nanorod

TL;DR

This paper investigates how a rotating elastic nanorod can undergo a shape transition at a critical torque, resulting in a significant forward propulsion, demonstrating a nanomechanical force-rectification mechanism.

Contribution

It reveals a shape bifurcation in rotating elastic filaments leading to propulsion, introducing a novel nanomechanical force-rectification concept.

Findings

Discontinuous shape bifurcation at critical torque

Forward propulsion regardless of rotation direction

Establishment of a nanomechanical force-rectification device

Abstract

The dynamics of a rotating elastic filament is investigated using Stokesian simulations. The filament, straight and tilted with respect to its rotation axis for small driving torques, undergoes at a critical torque a strongly discontinuous shape bifurcation to a helical state. It induces a substantial forward propulsion whatever the sense of rotation: a nanomechanical force-rectification device is established.