U.S. government researchers have created half-millimeter wide robots that assemble themselves from free-floating particles and transport objects four times their size.
The technology bridges a gap in the manipulation of objects that exists between laser-powered tweezers and mechanical micromanipulators, according to the Department of Energy.
The salt grain-sized robots are built from particles that move in response to magnetic fields. To create them, scientists put these particles between layers of non-mixing fluids. When a magnetic field is applied, the particles arrange themselves into spiky, circular shapes the scientists call asters.
When a second magnetic field is applied, the robots begin to move. By changing this magnetic field, the researchers can control the robots.
"We can make them open their jaws and close them," Alexey Snezhko, a researcher with the Argonne National Laboratory in Illinois and one of the robots' creators, said in a news release. "This gives us the opportunity to use these creatures as mini-robots performing useful tasks."
In the video above, the robot picks up a glass bead that is four times as heavy as the robot. In the video below, the robots swim in formation and corral free-floating particles like a miniature vacuum cleaner.
The robots were particularly adept at picking up and moving objects without smashing them, a problem encountered with mechanical micromanipulators, according to the researchers. They could find work in the fabrication of precisely designed functional materials.
What's more, the robots can repair themselves. If a particle is lost, for example, the robot reshuffles itself and keeps going.
More on robots:
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- A new DNA robot gets with the program
- Obama visits institute to 'keey an eye on robots
The research was supported by the Department of Energy's Office of Science. A paper on the robots was published online Aug. 7 in Nature Materials. Igor Aronson, also of Argonne National Laboratory, is a co-author on the paper.
John Roach is a contributing writer for msnbc.com.