The self-folding robot crawling in three stages. Credit: Seth Kroll, Wyss Institute, Harvard University

New Delhi, Aug. 7: The traditional Japanese craft of folding paper into complex shapes and figures has inspired ideas to build a new generation of robots.

A team of engineers in America has borrowed the principles of origami to build a prototype robot that starts as a fully flat sheet, folds itself into a complex 3D shape, and crawls.

Researchers at the Massachusetts Institute of Technology (MIT) and Harvard University today announced they had built a tabletop robot that can fold itself into a complex shape in four minutes and walk without human intervention, ready to be turned into a functional machine.

“We’ve put just enough brain power for the robot to fold and to crawl,” Sam Felton, a team member at Harvard, told The Telegraph. “We’ll need to build more intelligence into such robots for real-world applications.”

Felton and his colleagues have described their work in a paper that will appear tomorrow in the US journal Science.

The researchers say their self-folding robot demonstrates a process to create self-assembling machines with complex structures and movement capabilities.

They predict that such origami-inspired techniques may be used to rapidly fabricate small, even centimetre-sized, robots for tasks in environments too hazardous for humans such as disaster zones or industrial plants.

“This technology may also be used to fabricate satellites that self-assemble in space,” said Felton.

With a size of about 15cm by 15cm by 10cm, the robot is constructed from what engineers call shape memory composites that can alter their shapes in response to various triggers such as an electric current or activation through a wireless command.

The flat composite has electronics embedded within the material and the folding is driven by a microprocessor — a tiny computational machine — that serves as the robot’s brain. Tiny hinges in the composite determine the sequence of folds and the robot’s 3D shape.

As a concept, a self-folding machine isn’t new. The aerospace sector has long been using systems that change shapes in space — communication antennae or solar panels that unfold after a satellite reaches its intended orbit.

The structures and mechanisms are deployed from one compact stored shape to another larger desired shape by using energy from springs or electric motors.

But the MIT-Harvard team has designed a machine capable of computational and controllable functions on the completion of the self-folding process.

The machines just “get up and go, and this is new”, Daniela Rus, professor of mechanical engineering at MIT, told this newspaper. “The control and computational layers are built into the structure itself.”

“The novelty and the really nice thing about this new concept is the use of origami,” said Asitava Ghoshal, a scientist at the Indian Institute of Science, Bangalore, who was not associated with the work.

“Origami allows various folded and unfolded shapes to be formed from a simple single sheet. These features will potentially allow many different shapes to be formed and this is a significant advance in robotics.”

Robots made through this technique could be tailored into specific shapes and sizes for use in myriad environments.

The spontaneous folding displayed by the MIT-Harvard robot resembles in a rudimentary manner the folding mechanisms portrayed by the set of fictional robots called Transformers featured in the Hollywood movie series of that name.

But Transformer-type robots have the ability to reverse the folding process and even change their shapes multiple times.

“Being compared with (the) Transformers is flattering, but what we’ve got thus far is only a one-way folding process,” Felton said.