A team of physicists from Cornell University in the US has developed electricity-conducting, environment-sensing, shape-changing robots the size of a human cell.
The robots – described in the journal Proceedings of the National Academy of Sciences – are made from atomically thin layers of graphene and glass. Known as biomorphs, the tiny machines bend when exposed to stimuli including heat, chemical reactions or electricity. They can transform in a fraction of a second from two dimensional planes into complex three-dimensional forms such as tetrahedra and cubes.
Team member Paul McEuen says the biomorphs are designed as carriers for even smaller, but potentially very powerful, bits of photonic, electronic or chemical kit.
“We are trying to build what you might call an ‘exoskeleton’ for electronics,” he says. “Right now, you can make little computer chips that do a lot of information-processing, but they don’t know how to move or cause something to bend.”
The biomorphs’ ability to change shape arises from the fact that glass and graphene react differently to stimuli. Because they expand at different rates in response to a common input, the difference can be quite easily engineered into a stress-relieving curve or angle.
Such origami-style nanobots are not unique, but the scientists claim the Cornell versions have a clear advantage.
“Our devices are compatible with semiconductor manufacturing,” says team member Itai Cohen. “That’s what’s making this compatible with our future vision for robotics at this scale.”
The biomorphs are described as being three times larger than a red blood cell, but three times smaller than a large neuron.
Tiny the robots may be, but the physicists say the inherent strength of graphene means they are capable of carrying significant payloads, opening up a whole range of opportunities.