PMMH ESPCI-ParisTech-CNRS UMR-Universit Paris, France.
Phys Rev Lett. 2011 Jul 1;107(1):014501. doi: 10.1103/PhysRevLett.107.014501. Epub 2011 Jun 27.
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 microcarpets 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.
我们结合技术、实验和理论方面的努力，研究了粘性流体中人工微纤毛的集体动力学。我们利用软光刻和胶体自组装技术设计了由数百根细长磁棒组成的微地毯。这种新颖的实验装置用于研究由进动磁场驱动的扩展纤毛阵列的动力学。虽然单个纤毛的动力学是刚体旋转，但集体拍打会导致进动模式的对称破缺。纤毛的轨迹是各向异性的，并随着激励频率的增加经历显著的结构演化。我们提出了一个最小模型来解释我们的实验结果，并展示了通过远程水动力相互作用，阵列的整体几何形状如何对轨迹的形状施加影响。
