Scientists have developed a robotic system that can switch from solid to liquid and back again, making a bit of classic sci-fi lore a reality. It’s been three decades since the T-1000 robot from Terminator 2: Judgment Day scared us with its shape-shifting abilities, but now an international team of researchers has made a version of it in the real world – with more benevolent intentions.
The team drew inspiration from the sea cucumber, which can transition between soft and rigid bodies. “Giving robots the ability to switch between liquid and solid states endows them with more functionality,” says Chengfeng Pan, an engineer at The Chinese University of Hong Kong who led the study.
To show off this increased functionality, the researchers placed one of their miniature robots in a simulated jail cell and showed how it could escape. It melted down to a liquid, flowed between the bars, and into a waiting mold where it cooled, reformed itself, and then popped back up.
This was all made possible by magnets, which the team detailed in a study published Wednesday in the journal Matter. Senior author Carmel Majidi from Carnegie Mellon University said the magnetic particles have two roles: they make the material responsive to an alternating magnetic field, allowing for the phase change, and they give the robots mobility and the ability to move in response to the magnetic field.
The particles are embedded in gallium, which has a very low melting point of 86 degrees Fahrenheit (about 30 Celsius), creating a substance that flows more like water than other phase-changing materials. In tests, the mini robots could jump over obstacles, scale walls, split in half and re-merge all while being magnetically controlled.
The researchers envision the system being able to conduct repairs in hard-to-reach spaces and serving as a “universal screw,” which melts into a screw socket and solidifies with no actual screwing required. They’re also excited about the potential medical uses, such as drug delivery or removing foreign objects.
Hopefully, the list of foreign objects that need removal won’t ever include weaponized miniature melting robots, as they might prove difficult to track down and extract.
