It’s been 30 years since liquid metal killer robots entered our nightmares with the 1991 film Terminator 2: Judgment Day, where the T-1000 wererobot could overcome any obstacle by turning parts of its body into arms. Scientists at the University of Hong Kong have somehow realized this nightmarish vision by creating a tiny robotic system that can switch from solid to liquid and back again.
The team says it wasn’t Hollywood that inspired them, but the sea cucumber, which can go from soft to hard. “Giving robots the ability to go from liquid to solid gives them more functionality,” says Chengfeng Pan, an engineer at the University of Hong Kong who led the study.
The researchers demonstrated the capabilities of their robot by placing it in a cage, from which it escaped by changing shape. In the video below, the robot turns into a liquid, passes between the rods and enters the mold, where it cools, transforms and exits. The demonstration is part of a study published in the journal Matter.
According to lead author Carmel Majidi of Carnegie Mellon University, magnets make this phase transition possible. “Magnetic particles play two roles here… On the one hand, they make the material sensitive to an alternating magnetic field, so that we can inductively heat the material and cause a phase transition. On the other hand, magnetic particles give robots mobility and the ability to move in response to a magnetic field. »
The particles are encapsulated in gallium, a metal with a very low melting point of just 30 degrees Celsius, which creates a more liquid substance than other more viscous phase change materials. In tests, these mini-robots could jump over obstacles, climb walls, split in two and merge again, all under magnetic control.
“Now we are using this material system in a more practical way to solve very specific medical and technical problems,” says Chengfeng Pan. In other demonstrations, robots have been used to solder chains, administer drugs, and remove a foreign body from an artificial stomach.
The researchers suggest that the system could be used to repair hard-to-reach areas and act as a “universal screw” by melting into the cavity before hardening, eliminating the need for screwing. The team is particularly enthusiastic about potential medical applications.
“Future work should further explore how these robots can be used in a biomedical context,” continues Carmel Majidi. “What we are showing is just a one-off demonstration, a proof of concept, but further research will be needed to gain a deeper understanding of how this could actually be used for drug delivery or foreign body removal. »
CNET.com article adapted by CNETFrance
Image: CNET.com video