A team of researchers at MIT, the University of Sheffield, and the Tokyo Institute of Technology presented a super small origami robot that is capable of unfolding itself from a capsule after being swallowed. The robot can then be 'driven around' your insides with the help of external magnetic fields and play a key role in removing a swallowed button battery - which is not that uncommon (around 3,500 per year are reported in the U.S. alone) - as well as treating of consequent wounds.

According to MIT News, the new robot consists of two layers of heat-sensitive structural material sandwiching a material that shrinks when heated. A pattern of slits in the outer layers determines how the robot will fold when the middle layer contracts. 

As the structural material, a type of dried pig intestine commonly used in sausage casings was used. The contracting layer was created out of a biodegradable shrink wrap called Biolefin. The creation was then compressed and encased in an ice capsule that disolves in the stomach and lets the robot unfold in all its digital glory. 

"This concept is both highly creative and highly practical, and it addresses a clinical need in an elegant way," says Bradley Nelson, a professor of robotics at the Swiss Federal Institute of Technology Zurich. "It is one of the most convincing applications of origami robots that I have seen."