Scientists have created a tiny robotic system that can go from solid to liquid and back again, bringing a bit of classic sci-fi history to life.
It’s been 30 years since killer liquid metal robots invaded our nightmares courtesy of 1991’s Terminator 2: Judgment Day. This film’s shape-shifting T-1000 robot could seemingly overcome any obstacle while turning parts of itself into weapons at will.
The specter of Skynet and the robot apocalypse have haunted us ever since, and now an international team of researchers has finally given us a real-world version of a T-1000, albeit with rather altruistic goals.
The team says it wasn’t inspired by Hollywood, but by the humble sea cucumber, which can switch between soft and rigid body states.
“Enabling robots to switch between liquid and solid states gives them more functionality,” he says Chengfeng panan engineer at the Chinese University of Hong Kong, who led the study.
As if to hint at Terminator-inspired night terrors, Pan and colleagues demonstrate this expanded functionality by placing one of their miniature robots in a simulated prison cell and showing how it might escape.
It can be a little tricky to see what’s going on in the video above, but basically the robot melts into a liquid, flows between the wands and into a waiting form where it cools, reforms and then re-emerges. Granted, this runaway is a little less scary than a T-1000 in that it needs a form ready to reconstruct itself, but it’s still enough to excite any Luddite.
The demonstration is part of a study published Wednesday in Matter magazine.
Lead author Carmel Majidi of Carnegie Mellon University said magnets make all of these futuristic phase transitions possible.
“The magnetic particles have two roles here… One is that they make the material respond to an alternating magnetic field, so you can use induction to heat the material and cause the phase change. But the magnetic particles also give the robots mobility and the ability to move in response to the magnetic field.”
The particles are embedded in gallium, a metal with a very low melting point of just 86 degrees Fahrenheit (about 30 degrees Celsius), creating a substance that flows more like water than other phase change materials, which are more viscous.
In tests, the mini-robots could jump over obstacles, scale walls, split in half and merge back together while being magnetically controlled.
“Now we’re pushing this material system in a more practical way to solve some very specific medical and engineering problems,” Pan said.
In other demonstrations, the robots were used to solder circuits, administer medication, and remove a foreign object from a model stomach.
Researchers envision the system being able to make repairs in hard-to-reach places and serve as a “universal screw” that melts into a screw socket and solidifies without actual screwing being required.
The team is particularly excited about the potential medical applications.
“Future work should further explore how these robots could be used in a biomedical context,” Majidi said. “What we are showing are just one-off demonstrations, proofs of concept, but many more studies are needed to explore how this might actually be used for drug delivery or foreign body removal.”
Hopefully the list of foreign objects to remove never includes armed miniature smelting robots, as they might prove difficult to track down and extract.
