Skip to Content
77 Mass Ave

Ingestible Origami Robot

Robot unfolds, removes button battery from simulated stomach.

In experiments involving a simulation of the human esophagus and stomach, researchers at MIT, the University of Sheffield, and the Tokyo Institute of Technology have demonstrated a tiny origami robot that can unfold itself from a swallowed capsule and crawl along the stomach wall to patch a wound or remove a swallowed button battery. Every year, 3,500 swallowed button batteries are reported in the U.S. alone. The batteries can cause a chemical reaction that can lead to disfigurement and even death.

The robot propels itself chiefly through a “stick-slip” motion, in which its appendages stick to a surface through friction when it executes a move but slip free when its body flexes to change its weight distribution. It can also push against fluid like an oar.

The robot is rectangular, with accordion folds perpendicular to its long axis and pinched corners that act as points of traction. In the center of one fold is a permanent magnet that responds to changing external magnetic fields, which control the robot’s motion.

Once swallowed, the capsule (left) is designed to release a robotic device (right) made of two structural layers sandwiching a material that shrinks when heated. A pattern of slits in the outer layer determines how the robot will fold when the middle layer contracts.

In their search for biocompatible materials to serve as the robot’s structural layers, the researchers “spent a lot of time at Asian markets and the Chinatown market,” says Shuguang Li, a postdoc in Professor Daniela Rus’s research group, which led the new work. They finally settled on the type of dried pig intestine used in sausage casings.

The researchers’ test bed is an open cross-section of the stomach and esophagus, molded from a silicone rubber with the sponginess and flexibility of a pig’s stomach. A mixture of water and lemon juice simulates the stomach fluids.

Keep Reading

Most Popular

Europe's AI Act concept
Europe's AI Act concept

A quick guide to the most important AI law you’ve never heard of

The European Union is planning new legislation aimed at curbing the worst harms associated with artificial intelligence.

Uber Autonomous Vehicles parked in a lot
Uber Autonomous Vehicles parked in a lot

It will soon be easy for self-driving cars to hide in plain sight. We shouldn’t let them.

If they ever hit our roads for real, other drivers need to know exactly what they are.

supermassive black hole at center of Milky Way
supermassive black hole at center of Milky Way

This is the first image of the black hole at the center of our galaxy

The stunning image was made possible by linking eight existing radio observatories across the globe.

transplant surgery
transplant surgery

The gene-edited pig heart given to a dying patient was infected with a pig virus

The first transplant of a genetically-modified pig heart into a human may have ended prematurely because of a well-known—and avoidable—risk.

Stay connected

Illustration by Rose WongIllustration by Rose Wong

Get the latest updates from
MIT Technology Review

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

Explore more newsletters

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at customer-service@technologyreview.com with a list of newsletters you’d like to receive.