Batch Manipulation of Submillimeter-Scale Particles in a Water-Filled Rectangular Container

Small particles scattered at the bottom of a water-filled rectangular container align at specific locations when the container is laterally oscillated at specific frequencies. This paper proposes a batch manipulation method of submillimeter-scale particles utilizing this unique phenomenon. First, behavior of water in the laterally oscillated container was analyzed to identify oscillation frequencies that allow the particles to align at the specific locations. We assumed that the particles drift toward positions where lateral fluid velocity and its variation are zero at the bottom of the container. The positions were estimated by simulating the fluid behavior under the oscillation at the frequencies identified by a nonlinear programming. Using an experimental platform, alignment conditions were experimentally investigated by sequentially changing the oscillation frequency in order to examine validity of the analytical solutions. The results demonstrated that drifting of the particles toward the estimated positions was feasible and that the surface tension effect of liquid should be included in the fluid model for improving the estimation. Additionally, this study proposed a position control method of the particles with the analytical results and discussed the applicability as a new micromanipulation method.