Cheang U Kei, Meshkati Farshad, Kim Dalhyung, Kim Min Jun, Fu Henry Chien
Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, Pennsylvania 19104, USA.
Department of Mechanical Engineering, University of Nevada, Reno, Reno, Nevada 89557, USA.
Phys Rev E Stat Nonlin Soft Matter Phys. 2014 Sep;90(3):033007. doi: 10.1103/PhysRevE.90.033007. Epub 2014 Sep 12.
Controllable propulsion of microscale and nanoscale devices enhanced with additional functionality would enable the realization of miniaturized robotic swimmers applicable to transport and assembly, actuators, and drug delivery systems. Following biological examples, existing magnetically actuated microswimmers have been designed to use flexibility or chirality, presenting fabrication challenges. Here we show that, contrary to biomimetic expectations, magnetically actuated geometries with neither flexibility nor chirality can produce propulsion, through both experimental demonstration and a theoretical analysis, which elucidates the fundamental constraints on micropropulsion via magnetetic rotation. Our results advance existing paradigms of low-Reynolds-number propulsion, possibly enabling simpler fabrication and design of microswimmers and nanoswimmers.
具有附加功能增强的微尺度和纳米尺度装置的可控推进，将使适用于运输和组装、致动器及药物输送系统的小型化机器人游泳器得以实现。仿照生物学实例，现有的磁驱动微游泳器已被设计成利用柔韧性或手性，这带来了制造挑战。在此我们表明，与仿生预期相反，既无柔韧性也无手性的磁驱动几何结构可通过实验演示和理论分析产生推进力，该理论分析阐明了通过磁旋转实现微推进的基本限制。我们的结果推进了低雷诺数推进的现有范式，可能使微游泳器和纳米游泳器的制造和设计更简单。
