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arXiv · 1103.3122

Collective beating of artificial microcilia

Naïs Coq·Antoine Bricard·Francois-Damien Delapierre·Laurent Malaquin·Olivia du Roure·Marc Fermigier·Denis Bartolo
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Abstract

We combine technical, experimental and theoretical efforts to investigate the collective dynamics of artificial microcilia in a viscous fluid. We take advantage of soft-lithography and colloidal self-assembly to devise microcapets made of hundreds of slender magnetic rods. This novel experimental setup is used to investigate the dynamics of extended cilia arrays driven by a precessing magnetic field. Whereas the dynamics of an isolated cilium is a rigid body rotation, collective beating results in a symmetry breaking of the precession patterns. The trajectories of the cilia are anisotropic and experience a significant structural evolution as the actuation frequency increases. We present a minimal model to account for our experimental findings and demonstrate how the global geometry of the array imposes the shape of the trajectories via long range hydrodynamic interactions.

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Naïs Coq, Antoine Bricard, Francois-Damien Delapierre, Laurent Malaquin, Olivia du Roure, Marc Fermigier, Denis Bartolo. 2011-03-16. Collective beating of artificial microcilia. https://doi.org/10.1103/physrevlett.107.014501

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