A wireless capsule robot with spiral legs for human intestine

摘要

BACKGROUND: As an attractive alternative to traditional diagnostic techniques, wireless capsule endoscopy (WCE) can be considered a disruptive technology. METHODS: This paper presents a wirelessly powered micro-robot based on the Archimedes spiral with high integration of an active locomotion module. RESULTS: A WCE prototype was fabricated and tested. Including the video camera and end cap, the outer dimensions of the capsule were diameter (Φ) 16 mm, length 45 mm. Experiments demonstrated that the anchoring force can overcome 2.6 N wrap force on each leg. The anchoring force was improved to 1.486 with textured legs. A series of ex vivo experiments evaluated capsule performance and ability to traverse the intestine at an average speed of 2.3 cm/min. The wireless power transmission utilized a cylinder ferrite-core in the receiving coil-set, which significantly improved the coupling efficiency (to 12%) in the direction close (and parallel) to the transmitting coil. CONCLUSIONS: Although improvements of the wireless power transmission should target increased stability, this WCE device is both safe and practical for endoscopy.