A robot capable of crawling through the intestine has just reached a promising milestone.
The small intestine is a long tube folded back on itself, located between the stomach and the large intestine. In adults, it measures several meters. Doctors may need to look for bleeding, inflammation, or a small lesion inside it. Yet reaching its deeper sections with instruments remains difficult.
Close-up of the flexible BIOSENTER robot placed inside a transparent tube, with textured ends designed to improve its grip.
Credit: study researchers / MIT.
To achieve this, MIT researchers designed BIOSENTER, a flexible robot that moves forward by deforming itself. It reproduces some of the movements of snakes, but has neither wheels nor legs. Its body consists of a tube containing several small air-inflated pockets. Depending on which pockets are used, it lengthens or bends.
The robot also has two other inflatable zones, at the front and rear. They take turns bracing against the intestinal wall, allowing it to move forward. Their surface has tiny ridges that unfold when inflated. These ridges improve grip on a naturally slippery wall without requiring high pressure.
Above all, the robot is not used only for movement. A passage allows a camera and small instruments to be used. It can therefore observe tissue, take a sample for analysis, or deliver liquid to a precise location. Such a sample is a biopsy: it helps doctors look for disease.
The first trials took place in pigs. During the experiments, the robot traveled approximately 2 meters through the small intestine in 11 minutes. The researchers also tested camera-based observation, tissue sampling, and local liquid delivery. These results demonstrate the feasibility of several procedures.
Before any medical use, the robot's behavior over longer distances will need to be verified, and the risks to tissue studied. Its navigation also needs to be improved, as it still depends on an external control system. The goal is to gradually make its movements more autonomous while preserving the doctor's ability to guide it.