Shape Shifting Liquid Metal Could Revolutionize Robotics
From self-healing robots to reconfigurable electronic circuits, the applications of liquid metal are only limited by the imaginations of the scientists working with them. Let's take a look at some of the latest revolutions, discoveries, and innovations in this material.
2D morphing metal
In 2017, scientists at the University of Sussex and Swansea University invented a way to morph liquid metal into 2D shapes using an electrical charge. Though still in the early stages of development, this team's research could open up new possibilities in soft robotics, smart electronics, computer graphics, and flexible displays.
Because the electric fields used to shape the liquid are programmed by a computer, the position and shape of the liquid can be programmed and controlled dynamically.
“Liquid metals are an extremely promising class of materials for deformable applications; their unique properties include voltage-controlled surface tension, high liquid-state conductivity, and liquid-solid phase transition at room temperature," said Professor Sriram Subramanian, head of the INTERACT Lab at the University of Sussex, in a press release.
Carnegie Mellon Metal Alloy
That same year, research engineers at Carnegie Mellon University created a metal alloy that exists in a liquid state at room temperature and can capacitate liquid metal transistors, flexible circuitry, and perhaps even self-repairing circuits in the far-flung future.
Created at the Soft Machines Lab at Carnegie Mellon by researchers Carmel Majidi, Michael Dickey, and James Wissman, this alloy is the result of a combination of indium and gallium. It would only take two drops of this liquid metal to form or break a circuit thereby opening or closing an entry, similar to a traditional transistor. Better yet, it only requires a voltage of 1 - 10 volts.
In early 2020, a team of researchers at Tsinghua University in China created a liquid metal material so light that it can float on water. The researchers believe it could be used to construct lightweight exoskeletons and shape-shifting robots, as per New Scientist's report.
Like the researchers at Carnegie Mellon, those at Tsinghua University used a mixture of gallium and indium for their material. To make it float, the team stirred air-filled glass beads of glass into the liquid.
Despite its extremely low density, the liquid metal material “still maintains excellent conformability, electric conductivity, and stiffness variety under temperature regulation” according to the paper published in the journal Advanced Functional Materials.
It will likely take some time before we see shape-shifting floating robots or self-repairing circuits in our daily lives. But in a few decades, these innovations could revolutionize how we think about metal.