Scientists have created a small robotic system that can transition from a solid to a liquid form and back again, finally bringing a bit of classic science fiction to life.
It’s been 30 years since liquid metal killer robots entered our nightmares courtesy of 1991’s Terminator 2: Judgment Day. The shape-shifting T-1000 robot from that movie could seemingly overcome any obstacle while converting parts of itself. in arms 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 more altruistic goals.
The team says it wasn’t inspired by Hollywood, but by the humble sea cucumber, which can transition between soft and rigid body states.
“Giving robots the ability to switch between liquid and solid states gives them more functionality,” he says Chengfeng frying panan engineer at the Chinese University of Hong Kong who led the study.
As if to nod to Terminator-inspired night terrors, Pan and his colleagues demonstrate this increased functionality by placing one of their miniature robots in a simulated prison cell and showing how it could escape.
It might be a little hard to see what’s going on in the video above, but basically the robot melts into a liquid, flows between the bars and into a holding mold where it cools, reforms, and then reappears. Granted, this runaway is a bit less scary than a T-1000, since it needs a ready cast to reconstitute itself, but it’s still enough to shake any Luddite.
The demo is part of a study published Wednesday in the journal Matter.
Lead author Carmel Majidi, of Carnegie Mellon University, said magnets make all of this futuristic phase transition possible.
“The magnetic particles here have two functions… One is that they make the material respond to an alternating magnetic field, so it can, through induction, heat the material and cause the phase change. But the magnetic particles they also give robots mobility and the ability to move in response to the magnetic field.”
The particles are embedded in gallium, which is a metal with a very low melting point of just 86 degrees Fahrenheit (around 30 degrees Celsius), creating a substance that flows more like water than other phase-changing materials, which are more viscous.
In tests, the mini robots were able to jump over obstacles, scale walls, split in half, and merge back together, all while being magnetically controlled.
“Now, we are advancing this system of materials in more practical ways to solve some very specific medical and engineering problems,” Pan said.
In other demonstrations, the robots were used to solder circuitry, administer medication, and remove foreign objects from a model stomach.
The researchers envision the system being able to make repairs in hard-to-reach spaces and serving as a “universal screw,” casting into a screw socket and solidifying without the need for screwing.
The team is particularly excited about the potential medical uses.
“Future work should further explore how these robots could be used within a biomedical context,” Majidi said. “What we are showing are just one-off demonstrations, proofs of concept, but many more studies will be required to dig into how this could actually be used for drug delivery or foreign object removal.”
Hopefully the list of foreign objects to be removed will never include weaponized miniature fusion robots, as they could prove difficult to track down and extract.