Scientists have created tiny magnetically-manipulated robots. But why? It turns out there are lots of applications for a controllable substance that can fit into tight spaces. As seen in New Scientist, a magnet-based slime could reduce the invasiveness of some surgeries. The researchers aimed to combine the benefits of elastic and fluid-based soft robots. Their magnetic slime can squeeze through narrow channels better than previous elastic robots. But it also reconstitutes and heals itself better than other liquids.
The peer-reviewed journal Advanced Functional Materials published the results. The report includes several short videos of the slime in action. The researchers used neodymium, a strongly magnetic metal. It is also conductive, meaning the slime can repair electric current between cut wires. Manipulation on a small scale gives it the ability to grasp objects. The scientists tested the magnetic slime robot on a variety of surfaces and even underwater.
A silicon coating covers the neodymium particles to make them safe for use in the human body. In one video, the slime enters a model of the digestive tract. It scoops up a small battery and then exits the other side. Ironically, neodymium magnets are illegal in certain countries specifically because they can pinch the digestive tract if swallowed. Emergency room visits skyrocketed in 2016 after the US lifted its ban. They are also strong enough to cut or even break fingers when two magnets snap together.
Another group of scientists developed gears as small as a hundredth of an inch across. They are controlled by magnetic fields and can be combined into modular robots. The video below shows their ability to jump or crawl inside the human body. One is even fitted with a needle in order to deliver drug therapies or take samples. The research was published in the peer-reviewed journal Science Robotics.
While we wait for crawling or slime robots to take over the world, other magnetic fluids already exist. Ferrofluids have plenty of uses, though many are more cool than functional. Like making a Venom costume or a lava lamp. You can even make a version of a less toxic magnetic slime at home as a science experiment. But let’s leave the medical procedures and other scientific applications, not to mention the hard-core magnets, to the experts. Magnetic robots belong only in capable hands.
Originally published on April 1, 2022.
Featured Image: New Scientist