Robots are not all huge walking contraptions, ripe for abuse by human engineers. Some of them are small enough to operate inside the human body, and that’s exactly what a new robot developed at MIT is all about. The “ingestible origami robot” can fold up inside a pill to be swallowed. After unfolding itself, the robot can be steered around to clear obstructions or patch wounds by doctors on the outside.

It took a number of prototypes before the team settled on a material for the robot’s frame — dried pig intestine. So, this is pretty much a robot made out of sausage casing that shrinks when heated. It consists of two layers of structural sausage material with inlaid magnetic components. A pattern of slits in the structure determines its folded shape.

The origami bot was developed at MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) with the aid of researchers from the University of Sheffield and the Tokyo Institute of Technology. As the name implies, the ingestible origami robot begins life folded up inside a pill. For its test, MIT scientists use a pill-shaped ice capsule to move the robot through a simulated esophagus and stomach. Once it’s in the stomach, the ice melts and the robot unfolds, ready for action.

The origami bot can propel itself (via an external magnetic field) through a process called “stick-slip” motion. The robot’s flexible surface sticks to the stomach via friction when it moves, but it can slide along freely when the body flexes to change shape. The biocompatible makeup of this robot means it’s more flexible than similar robots, and that allows it to get about 20% of its movement from simple paddling force from its fin-like shape.

As for what it does, the initial test was the removal of a battery that had become embedded in the stomach lining. Thousands of people (mostly children) swallow coin cell batteries every year, and they can cause serious issues if they become stuck. The origami robot is quite adept at sliding over to the battery and dislodging it so it can be safely shepherded through the digestive tract. It can do this, of course, because it’s equipped with a magnet that allows doctors to control it from outside the body. MIT researchers also believe the biocompatible nature of the origami bot could allow it to patch internal wounds and give the body time to heal.

The team hoped to move on to tests in living patients soon, possibly with origami bots that can power themselves without an external magnetic field.