Design of spiral-type magnetic micro-machine with three-dimensional analysis of swimming properties

Magnetic micro-machines are driven by a magnetic field. They require no power supply cables, no batteries, and no controlling systems on the machine body. In previous studies, we examined the swimming properties of a spiral-type magnetic micro-machine (outer diameter of 0.1 or 1.5 mm) by the experiment and the analysis. This micro-machine is composed of the body of cylinder and the spiral structure. Pulling the thing and the transportation of the thing are given to the application of the micro-machine. At this time, a big load works in the machine. It is necessary to improve thrust to swim against the drag. In this paper, we examined about the influence that machine shape and a spiral shape give to the swimming properties of micro-machie using the analysis. As machine shapes, the having body (Ref-Type) and no (Head-Type) were examined. As a spiral shape, the blade pitch was examined. It was found that the micro-machine of Head-Type suitable for the micro-machine that pulled the thing because the thrust was large. In the case of Ref-Type with the loading on the machine body, the spiral pitch of the maximum thrust was about 1 mm.