Your Next Surgeon Could Be a Slime Robot

When you think of robotic surgery, you might think of remotely controlled robotic arms whirring over a patient, or tiny endoscopic cameras that help surgeons navigate with precise instruments.

You probably don't think of a magnetically controlled slime robot slithering through your gastrointestinal tract and swallowing objects, like some kind of sci-fi ooze. 

But that's the exact idea behind the Reconfigurable Magnetic Slime Robot -- a stretchy, sluglike robot that can squeeze through tight spaces, wrap around objects and even "self heal" after it's been cut in two. 

Created by a team of researchers at the Chinese University of Hong Kong, the Slime Robot is a non-Newtonian fluid, meaning it can behave both as a solid and a liquid. This slime is made from a mixture of PVA and borax, but you can also make your own non-Newtonian fluid at home using cornstarch and water. 

According to Li Zhang, a professor from the Department of Mechanical and Automation Engineering at CUHK and one of the leads on the project, if you touch a non-Newtonian fluid at high speed, it behaves as a solid state object, but if you touch it gently and slowly, it behaves like a liquid. That behavior allows the robot to be stretchy enough to move around, but solid enough to wrap around objects like wires or ball bearings. 

"You can deform this material with an extremely large deformation, very much like how liquid can go through a tiny channel," said Zhang. "But sometimes it can behave like a solid, because we know if you want to use it as a robotic hand, then of course it needs to interact with the environment."

The control for the robot comes in the form of tiny magnetic particles, mixed into the fluid, which allows the slime to be manipulated with a magnetic field. It can be guided through tight spaces and channels using a single magnet, or anchored and stretched with two magnets. Or, if you rotate the controlling magnet, it behaves like what Zhang calls an "octopus arm," wrapping up or grasping objects "with ease."

Because the slime mixture is able to conduct electricity, Zhang also says the robot could be used to wrap around wires and repair circuits in hard-to-reach places. 

But the real hope for the Slime Robot is to test it for applications in internal medicine, where it could be used to pass through the gastrointestinal tract without causing damage. 

"Currently the idea is whether we can use a Slime Robot to encapsulate or swallow hazardous material in your stomach or your small intestine... for example, if someone swallows a battery by mistake," said Zhang. "Because this is a gel-like material, it's very soft and there's no sharp edges."

Watch the video above to see the Reconfigurable Magnetic Slime Robot stretching, wrapping and even self-healing.