Ferrofluidic Manipulator: Automatic Manipulation of Non-magnetic Microparticles at Air-Ferrofluid Interface

Zoran Cenev; P. A. Diluka Harischandra; Seppo Nurmi; Mika Latikka; Ville Hynninen; Robin H. A. Ras; Jaakko V. I. Timonen; Quan Zhou

doi:10.1109/tmech.2021.3081114

arXiv · 2101.02782

Ferrofluidic Manipulator: Automatic Manipulation of Non-magnetic Microparticles at Air-Ferrofluid Interface

Zoran Cenev·P. A. Diluka Harischandra·Seppo Nurmi·Mika Latikka·Ville Hynninen·Robin H. A. Ras·Jaakko V. I. Timonen·Quan Zhou

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Abstract

Manipulation of small-scale matter is a fundamental topic in micro- and nanorobotics. Numerous magnetic robotic systems have been developed for the manipulation of microparticles in an ambient environment, liquid as well as on the air-liquid interface. These systems move intrinsically magnetic or magnetically tagged objects by inducing a magnetic torque or force. However, most of the materials found in nature are non-magnetic. Here, we report a ferrofluidic manipulator for automatic two-dimensional manipulation of non-magnetic objects floating on top of a ferrofluid. The manipulation system employs eight centimeter-scale solenoids, which can move non-magnetic particles by deforming the air-ferrofluid interface. Using linear programming, we can control the motion of the non-magnetic particles with a predefined trajectory of a line, square, and circle with a precision of 25.1+/-19.5 um, 34.4+/-28.4 um and 33.4+/-26.6 um, respectively. The ferrofluidic manipulator is versatile with the materials and the shapes of the objects under manipulation. We have successfully manipulated particles made of polyethylene, polystyrene, a silicon chip, and poppy and sesame seeds. This work shows a promising venue for the manipulation of living and non-living matter at the air-liquid interface.

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Zoran Cenev, P. A. Diluka Harischandra, Seppo Nurmi, Mika Latikka, Ville Hynninen, Robin H. A. Ras, Jaakko V. I. Timonen, Quan Zhou. 2020-12-30. Ferrofluidic Manipulator: Automatic Manipulation of Non-magnetic Microparticles at Air-Ferrofluid Interface. https://doi.org/10.1109/tmech.2021.3081114

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