Researchers developed a robot that employs a self-folding method inspired by the ancient art of origami.

The researchers found a way to coax flat sheets of composite materials to self-fold into robots with complex mobility, the American Association for the Advancement of Science reported. The findings were published in the August 8 edition of Science.

"We demonstrated this process by building a robot that folds itself and walks away without human assistance," said Sam Felton, a Ph.D. candidate at Harvard University's School of Engineering and Applied Sciences and the Wyss Institute for Biologically Inspired Engineering and the lead author the study.

The new robots formed themselves through paper and shape memory polymers; these materials responded to heat above 100 degrees Celsius. The flat composite proved to be able to transform itself into a functional machine in only about four minutes; the final product can crawl at a speed of two inches per second. The new approach allows researchers to produce complex robots that can be scaled to different sizes and are strong for their weight.

"Folding allows you to avoid the 'nuts and bolts' assembly approaches typically used for robots or other complex electromechanical devices and it allows you to integrate components (e.g., electronics, sensors, actuators) while flat," said Rob Wood, the Charles River Professor of Engineering and Applied Sciences Core Faculty Member at Harvard University's Wyss Institute for Biologically Inspired Engineering and the study's senior author.

The folding process is created through 3D design software that generates crease patterns in the polymer material; these creases can become a collection of creases known as cyclical folds.

"Cyclic folds are used by a software program called 'Origamizer' as building blocks to create any polyhedron," Felton said. "We've discovered that we can [use this approach] to create a wide variety of structures and machines."

These machines could be used in a wide range of search-and-rescue scenarios such as navigating small tunnels or the ruins of a collapsed building. The method could also be used to quickly prototype machines that are too small to be assembled by hand.  

"We envision combining these origami-inspired materials with computer-controlled actuators to build more complex machines, such as hardening shells, locked-in joints and deployable barriers; and ultimately, this transformer technology will revolutionize the way we think about materials, moving them beyond their current static form, and revealing more functionality than what originally meets the eye," Jesse Silverberg from Cornell University said.