It may sound like science fiction but university researchers have built a tiny, foldable robot that may one day operate on people -- from inside their body.
This tiny robot would be swallowed inside a capsule and then, once inside the patient's stomach, it would unfold itself and then crawl across the stomach to repair a wound or remove a swallowed button battery, for instance.
"It's really exciting to see our small origami robots doing something with potential important applications to health care," said Daniela Rus, an MIT professor who also directs the university's Computer Science and Artificial Intelligence Laboratory, in a statement. "For applications inside the body, we need a small, controllable, untethered robot system. It's really difficult to control and place a robot inside the body if the robot is attached to a tether."
So far, the robot has been tested on a synthetic stomach, made of silicone rubber and based on the mechanics of the stomach and esophagus of a pig.
For several years now, robots have been used in operating rooms to assist with surgeries.
This is the first time researchers have closed in on building a robot that could work from the inside of the body.
The research is being done by a group of scientists from MIT, the University of Sheffield, in England, and the Tokyo Institute of Technology.
MIT reported that the robot moves itself over the surface of the stomach by what they call a "stick-slip" motion.
That means the robot's appendages are made to stick to the surface using friction, but then slips free when its body flexes to make another move.
But that's not the only way the robot moves around.
MIT noted that since the human stomach is filled with fluids, 20% of the robot's forward motion is by propelling water or thrust.
Once in the stomach, the robot doesn't have to work its way out of the capsule it was swallowed in. The capsule itself is designed to dissolve, automatically freeing the robot.
The robot, rectangular in shape, is designed with accordion-like folds with a magnet on one of the folds that responds to magnetic fields outside the body. Using that magnet, doctors could manipulate the motion of the robot, moving it to where it needs to go.
So what is this robot made of?
It's built of the same dried pig intestine that is used in sausage casings, according to MIT.
"We spent a lot of time at Asian markets and the Chinatown market looking for materials," said Shuguang Li, a postdoc student at MIT working on the project, in a statement.