Physicists have come up with a robot exoskeleton that can change its shape according to the shifts it senses in its environment.
Tiny shape-shifting robot exoskeletons [Image by Cornell University]
The Transformers, perhaps the most famous of shape-shifting robots, are humongous metallic creatures that came from another planet. A newer kind of shape-shifting robots, however, have a terrestrial origin and are actually much, much smaller than Optimus Prime and his ilk. Also, these robots are very much real and not a part of yet another overdone franchise.
These tiny robots—or microscale machines, as their creators call them—came to be when physicists at the University of Cornell modified a “bimorph” motor composed of graphene and glass. Graphene and glass don’t respond to changes in heat in the same way or at the same rate, which means that the application of heat will make the bimorph’s shape change. The researchers outfitted the bimorphs with electronic, chemical, and photonic payloads, making them quite powerful for robots about the same size as our cells.
The bimorphs can fold and unfold as a response to chemical changes [Image by Cornell University]
Temperature changes aren’t the only things that the bimorphs respond to. They also react to chemical stimuli by pushing large ions into glass on the outer edge of the robots. This glass is highly reactive, and expands when the large ions drive into it.
“It’s a neat trick, because it’s something you can do only with these nanoscale systems,” says Marc Miskin, lead author of the study detailing the creation of the bimorphs.
So how do you build such complex robots while still keeping them microscopic? The researchers used a technique called atomic layer deposition, which entails “painting” atom-thin layers of silicon dioxide over aluminum. An atomic layer of graphene is then painted over the silicon dioxide, thus creating the thinnest biomorph yet. One of the biomorphs, according to the researchers, is as big as three blood cells when folded. This is equivalent to about a fifth of the width of human hair.
Don’t let the biomorphs’ size fool you, though. They’re actually relatively strong, due to the presence of graphene, which can handle loads required by electronic applications.
And that’s not all. “Our devices are compatible with semiconductor manufacturing,” says Itai Cohen, Miskin’s co-author. “That’s what’s making this compatible with our future vision for robotics at this scale.”
The power of a starship in a cell [Image by Cornell University]
An important question, of course, is what specifically could these robots be used for. As of now, they don’t have a specific purpose. There are also no plans as of yet regarding any practical applications, be it in electronics or anything else. However, that’s not to say that the bimorphs are remarkable, but not useful. At the very least, the creation of the bimorphs will be able to expand the burgeoning field of nanoscale robotics.
Still, it’s unlikely that that will be only thing that the bimorphs are good for. Even though as of now, the bimorphs don’t have a specific purpose, the possibilities are near-endless. “You could put the computational power of the spaceship Voyager onto an object the size of a cell,” Cohen posits. “Then, where do you go explore?”
Boldly to where no one has gone before, hopefully.
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