Design and Implementation of a Clamper-Based and Motor-Driven Capsule Robot Powered by Wireless Power Transmission

This paper proposes a clamper-based and motor-driven capsule robot (CMCR) for exploring the intestinal tract. The CMCR, measuring Φ14 mm×46.8 mm, is composed of a front facing camera, a clamper-based locomotion mechanism (LM), a telemetry circuit, and a solid-cylinder three-dimensional (3-D) receiving coil for wireless power induction. The LM consists of a translational mechanism (TM), a free clamper that can be moved linearly by the TM, and a fixed clamper. The two clampers both employ arc-shaped legs for expanding with diameters that range from 14 mm to 31 mm; and they can cooperate with the TM to simulate active locomotion in two modes. One mode contains four gaits and is used in an almost horizontal intestine, while the other mode contains six gaits and is used when the CMCR moves in a sloped intestine or against intestinal peristalsis. The solid-cylinder 3-D receiving coil is designed with an aim of maximizing its output power within a given available space, which is achieved by optimizing its design parameters with a calculation-based design method. Finally, the CMCR performance is tested: it works properly when powered by the solid-cylinder 3-D receiving coil, and has a satisfactory speed of 6.32 cm/min in a horizontal ex-vivo intestine and 2.69 cm/min in a vertical one. These test results indicate that the CMCR is promising for a minimally invasive intestinal exploration.