Origami Robot Can Self-Assemble and Walk Without Human Help

Over the course of four minutes, the origami robot slowly comes to life. Seth Kroll/Wyss Institute

A research team at Harvard and MIT announced today that they've created a self-assembling robot. The machine, which begins as a flat sheet of material, exploits principles of origami to fold itself into a 3-D robot capable of walking without any human assistance.

"We have achieved a long-standing personal goal to design a machine that can assemble itself," Daniela Rus, an MIT roboticist and one of the study's authors, said in a press conference about the robot.

The robot is made out of a flat multi-layered sheet of material outfitted with circuitry and motors. In this sheet, the researchers made slices (called hinges) along which folding will occur. The self-assembly works as follows: After the sheet is hooked up to a battery, heating elements embedded in the material activate. This temperature change prompts certain layers to contract. Guided by the hinges, the contraction causes the flat sheet to fold into a predetermined 3-D structure—in this case a walking robot. In all, the assembly process takes around four minutes.

After self-assembling, the authors reported in their study published in Science, the robot was able to crawl away at about 5.4 centimeters per second.

The design of the robot relies in large part on the field of computational origami—an algorithmic approach to investigating the mathematical properties of folding. One important finding in the relatively young field is that, as the authors wrote, "it is mathematically possible to fold arbitrary geometries from a single sheet of paper." That means, theoretically, a sheet of paper can be folded into any shape. Though the thickness of materials puts some constraint on this idea, they were able to show that their method for self-folding robots could be used to create just about any design.

From a practical perspective, one potential benefit of self-assembling robots is that they can be stored as flat sheets. Doing so greatly reduces the space—and thus the cost—of shipping machines. "This approach opens up possibilities for making robots that can be efficiently transported or perhaps used in a dangerous search and rescue mission where access to the site may be limited," Mark Lavine, a senior editor at Science, said in the press conference.

As the researchers note in their paper, the fact that the machines are self-folding also reduces the amount of time and skilled labor required to assemble them. Further, they don't necessarily need operators to turn them on. "[C]omplex triggers could be integrated, including wireless activation or response to an environmental change," the researchers wrote.

"By leveraging the knowledge and software tools developed for making paper art," Lavine said, "it may be possible to show rapid progress in these areas of robotics and materials science."