Chinese researchers at Tsinghua University are in the process of creating liquid metal devices, tools, and eventually special-use robots that are straight out of a Terminator tentpole. In their latest advancement, this ambitious team is now at the stage where a denser-than-water material injected with tiny glass beads could be the ticket to transformable machines and exoskeletons only seen in sci-fi blockbusters.
Similar to mercury, liquid metal has an extremely low melting point, has the ability to float on water, and does not solidify at normal room temperatures. To further the technology, scientists previously designed a controlled actuation of a gallium liquid metal mixed with indium, which could allow for the development of wheeled robots driven by liquid metal droplets.
For this new development assisting in the material's flotation properties, the team stirred in microscopic glass beads filled with air. Crafting a liquid metal robot might open up an entire field of special-use and micro robots that can adapt to difficult environments underwater or in emergency first responder situations.
In a paper published in the online journal Advanced Functional Materials in February, lead study author Jing Liu acknowledges that the material “still maintains excellent conformability, electric conductivity, and stiffness variety under temperature regulation. Such material is further adopted to build various complicated structures through origami or force regulation, representing various application scenarios and can be reused for eight times without evident loss in function."
This flotation advancement builds upon research discoveries made back in 2018, when Li Xiangpeng, a robotics professor at Soochow University in Suzhou, China developed a tiny robot powered by liquid metal. It was inspired by actor Robert Patrick's shape-shifting T-1000 assassin android from Terminator 2: Judgment Day and was comprised of a plastic wheel, a lithium battery, and drops of liquid metal. The bot’s wheel turns when liquid metal shifts its center of gravity by changing the battery's voltage level.
“In the future, we expect to further develop soft robots incorporating liquid metal that could be used in special missions such as searching for and rescuing earthquake victims, since they can change shape to slide under doors or make it through spaces humans can’t get into,” researcher Tang Shiyang explained to the South China Morning News.
Sure, it's not a killer robot stepping through metal bars or reconstituting itself after being blasted with a shotgun, but it's certainly a huge leap toward fabricating liquid metal machines that can replicate humanoid shapes!