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arXiv · 1212.1773

Dumbbell micro-robot driven by flow oscillations

Vladimir A. Vladimirov
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Abstract

In this paper we study the self-propulsion of a dumbbell micro-robot submerged in a viscous fluid. The micro-robot consists of two rigid spherical beads connected by a rod or a spring; the rod's/spring's length is changing periodically. The constant density of each sphere differs from the density of a fluid, while the whole micro-robot has neutral buoyancy. An effective oscillating gravity field is created via rigid-body oscillations of the fluid. Our calculations show that the micro-robot undertakes both translational and rotational motion. Using an asymptotic procedure containing a two-timing method and a distinguished limit, we obtain analytic expressions for the averaged self-propulsion velocity and averaged angular velocity. The important special case of zero angular velocity represents rectilinear self-propulsion with constant velocity.

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Vladimir A. Vladimirov. 2012-12-08. Dumbbell micro-robot driven by flow oscillations. https://doi.org/10.1017/jfm.2013.30

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