Miniature endoscopic capsule robot using biomimetic micro-patterned adhesives

Abstract

This paper presents a stopping and a locomotion mechanism to be used with an endoscopic microcapsule robot. In the diagnosis of gastrointestinal diseases, microcapsules have been developed recently as alternatives to conventional endoscopy. However, they have less accuracy and functionality in diagnosis as they lack the ability to control their position. We propose mechanisms to be used with such microcapsules that would enable them to anchor and crawl in any position inside the small intestines. The stopping mechanism, actuated by coil type shape memory alloys, makes use of dry and wet elastomer (PDMS) micro-patterned adhesives inspired by beetles to attach to the intestinal tract. The locomotion mechanism, inspired by the locomotion principles of inch-worms, is a modular expansion of the stopping mechanism. Both the stopping and the crawling locomotion mechanisms have been built and successfully tested inside a flexible vinyl tube. Results showed stopping with high repeatability and 0.5 mm/sec locomotion speed. The stopping mechanism was also integrated to a tethered camera for testing