At Carnegie Mellon University researchers are working on an intra-intestinal robot that is able to attach itself to cavity walls, opening up a possibility for new devices that would perform biopsies, deliver drugs, or administer localized treatment to the gut.
From MIT Technology Review:
Sitti [Metin Sitti, professor at NanoRobotics Lab at Carnegie Mellon] and his lab group looked to beetles, which secrete oil-like liquids along their foot hairs in order to stick securely to surfaces. They coated their robot’s feet with a similarly viscous liquid to “help get more adhesion by giving them a surface-tension component,” says Sitti. Aside from increasing capillary and intermolecular forces, secretions help feet adhere to rough surfaces by filling in the gaps, he adds.
The group attached three robotic legs to a standard capsule camera and covered microscopic fibers on the adhesion pads with biocompatible silicone oil. The capsule robot is one centimeter in diameter and three centimeters in length, with 1.5-centimeter-long feet that open on demand and press into the surface of the tissue to increase friction and anchor the device, says Sitti. In a recent paper published in the Journal of Adhesion Science and Technology, Sitti showed that the oil increased adhesion up to 25 percent over a dry attempt on a smooth surface. On a slightly rough surface, the oily layer improved adhesion by almost 6 times. Recently, the team demonstrated that the capsule robot can successfully anchor on animal intestines in vitro, says Sitti, as well as on an animal esophagus.