Washington Post reports on a swallowable, unfolding robot for retrieving the little batteries that little kids swallow:
Across the United States, a child swallows a battery once every three hours, according to one pediatric estimate, equal to about 3,300 cases annually. Based on emergency reports, the vast majority of swallowed batteries turn out to be button cells — the squat silver disks of electrochemical energy, used in hearing aids and TV clickers.
In a proof-of-concept experiment demonstrated at the International Conference on Robotics and Automation, the small device folds into an ice capsule about the size of a gummy bear. When the ice thaws inside the body, the robot unfurls as though it were a piece of origami filmed in reverse. Once flattened, the origami robot wriggles around the stomach, controlled by human operators using an external magnetic field.
“For applications inside the body, we need a small, controllable, untethered robot system,” said Daniela Rus, an electrical engineer at MIT who helped create the origami robot, in a press release. “It’s really difficult to control and place a robot inside the body if the robot is attached to a tether.”
The scientists also needed to create the robot out of safe-to-ingest parts. Sharp chips of metal and plastic were verboten, so they set their sights on food. “We spent a lot of time at Asian markets and the Chinatown market looking for materials,” MIT’s Shuguang Li said in the release. The final iteration of the origami bot is made of stiff pork casing — the same stuff you might find surrounding a hot dog or kielbasa.