A small ingestible robotic origami has been created by a team of researchers from the Massachusetts Institute of Technology (MIT), the University of Sheffield, and the Tokyo Institute of Technology. The device unfolds itself inside the stomach to remove foreign objects or repair a wound.

“It’s really exciting to see our small origami robots doing something with potential important applications to health care,” adds Daniela Rus, the Andrew and Erna Viterbi Professor in MIT’s Department of Electrical Engineering and Computer Science and the director of MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL). “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.”

The device can move by sticking its appendages to a surface through friction and change its weight distribution by flexing its body, just like its predecessor. The water inside one’s stomach also helps propel the origami.

The origami is composed of two layers that shrinks when heated. The patter of slits found on the device’s outside indicates how it will fold when the middle layer contracts.

Looking for the device’s material was not easy as the researchers spent huge amounts of time in Asian markets. After much research, the researchers opted to use the material called Biolefin for its shrinking layer.

The research team successfully tested the origami’s mechanical properties after replicating a person’s stomach by introducing a lemon and water mixture, which stood as the stomach’s acidic fluids, into a pig stomach. Now, foreign objects, which can cause more tissue damage with prolonged contact, can be easily and quickly removed with the device.

“Shuhei bought a piece of ham, and he put the battery on the ham,” says Rus. “Within half an hour, the battery was fully submerged in the ham. So that made me realise that, yes, this is important. If you have a battery in your body, you really want it out as soon as possible.”