Facilitating Displacement of a Micro-scale Liquid Marble Using Electric Fields

Abstract

This paper discusses a novel theoretical treatment for facilitating displacement of a micro-scale liquid marble. It can be beneficial in designing microsensors as liquid-state micro accelerometers. In this work, the marble has been placed on the substrate under which the finger electrodes are located. The marble has been bounded with another rigid plate above it. To overcome the complexities of the marble displacement, initially, it has been deformed utilizing the electric field. This deforming electric field is generated via applying a sufficient DC voltage to the top, and bottom fixed plates. The electrostatic manipulating force exerting on the marble opposes the marble’s gravity, reduces its contact zone area and eventually causes the marble to get spherical form approximately. For displacing the marble, another electric and considerably weaker field than deforming one is applied to the marble via finger electrodes. The displacing electric field, which causes the marble to roll, is created via applying a DC voltage to the finger electrodes underneath the substrate. The displacing potentials are set to be on and off regularly to accelerate the movement of the marble. It has been shown that for a liquid marble with an effective radius of 1 μm, applying the approximate value of 42 V can deform the marble to a spherical, shaped one. It was also indicated that the air friction force exerting on the marble during its displacement leads to the constant-velocity motion of the marble eventually.