If you eat something not fit for human consumption—like glass, or a battery—you'd better hope it comes back out your mouth, or out the other end. Otherwise, there are pretty good odds that you'll need surgery.
But that might all be changing soon, thanks to a team of scientists who have invented a little origami-shaped robot that can "unfold itself from a swallowed capsule and, steered by external magnetic fields, crawl across the stomach wall to remove a swallowed button battery or patch a wound."
Strange as this sounds, these are the very real results obtained by researchers at MIT's Computer Science and Artificial Intelligence Laboratory (CSAIL), whose research focuses on the medical potential of unfolding origami robots.
"It's really exciting to see our small origami robots doing something with potential important applications to health care," Daniela Rus, director of CSAIL and author of this recent study, said in a press 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."
But this innovation poses a larger question: How do you even make an origami robot ingestible? Pig intestine, that's how. After testing a dozen or so materials, the team finally agreed upon dried pig intestine, similar to what is used in sausage casings, as the ideal one. "We spent a lot of time at Asian markets and the Chinatown market looking for materials," Shuguang Li, a CSAIL postdoc student and researcher on the project, said.
The practical implications are pretty staggering, as the magnetically controlled robot can remove foreign objects, patch wounds, or deliver medicines. According to the research team, some 3,500 button batteries are swallowed by Americans every year (mostly children), which can cause significant health issues—like getting attached to the esophagus and causing burning.
In order to test this scenario, the CSAIL team once again headed down to the market. "[Co-author] Shuhei [Miyashita] bought a piece of ham, and he put the battery on the ham," Daniela Rus said. "Within half an hour, the battery was fully submerged in the ham. So that made me realize that, yes, this is important. If you have a battery in your body, you really want it out as soon as possible."
Battery eaters can breathe a sigh of relief, because with the assistance of the CSAIL meat-based robot, the battery could be removed by a remote-controlled robot and dispersed into the digestive tract. Needless to say, this is far easier and less invasive than surgery.
"This concept is both highly creative and highly practical, and it addresses a clinical need in an elegant way," Bradley Nelson, a professor of robotics at the Swiss Federal Institute of Technology Zurich, said of the breakthrough. "It is one of the most convincing applications of origami robots that I have seen."
Indeed it is.