Pinch locomotion: A novel propulsion technique for endoscopic robots

While the progress in imaging techniques more and more allows early and accurate diagnosis, minimally invasive intervention is still largely dependent on the availability of smart tools able to perform tasks inside the human body with a high level of autonomy. In this framework, endoscopic robots locomotion capabilities are needed to reach the site of interest, possibly with the desired orientation and with a firm grasping of the tissue. Current locomotion techniques do not provide sufficient degrees of mobility or are hardly miniaturizeable to the desired extent. In this paper we present the concept of a novel locomotion technique, called pinch locomotion, that relies upon and takes advantage of the large deformability of intestine to allow propulsion, steering and standing at a place with a continuous grasping of the tissue. The proposed locomotion technique is instantiated in a preliminary larger-scale prototype (70 mm×29 mm×10 mm), that is able to easily propel itself over a flexible stripe of cloth. The feasibility of a miniature endoscopic robot, endowed with the pinch-locomotion and with dimensions compatible to current swallable devices, is also investigated from a design perspective.