Self-assembling robots inspired by the ancient Japanese art of origami could provide a cheap way to mass-produce robots with multiple applications.
A team of engineers from Harvard and Massachusetts Institute of Technology have managed to coax flat sheets of composite materials into self-folding into complex robots that can then crawl and turn without human assistance.
The researchers believe technology could eventually lead to affordable 'robotic helpers' for use in everything from household chores to exploring space. The robots could be especially useful for accessing confined spaces in situation such as search and rescue operations – a ‘flat pack’ robot could be posted through a narrow gap or tunnel before expanding itself to full-size.
"Getting a robot to assemble itself autonomously and actually perform a function has been a milestone we've been chasing for many years," said Rob Wood of Harvard's School of Engineering and Applied Sciences.
"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."
The prototype robot, described in an article published in today’s edition of journal Science, was constructed from flat sheets of paper and shape memory polymers, which change shape when heated above 100˚ Celsius, into which the researchers had embedded electronics.
Heating circuits built into the composite were used to activate self-folding hinges and the flat composite took roughly four minutes to transform into a dynamic, functional machine before crawling away at a speed of about 5.4cm per second and turning.
Most importantly the whole process required no human help – a major breakthrough as no previous self-folding approach has yielded a machine that can function without outside assistance.
The team's robot prototype borrows mechanical principles from origami, with 3D design software used to generate detailed crease patterns in the polymer material. The robot also included motors, a microcontroller and batteries, which once they are hooked up, make the robot begin to fold into shape and perform its task.
According to Sam Felton, a Harvard Ph. D student who co-authored the research, the big innovation is the low-cost manufacturing process.
"These robots are inexpensive and (their) layered composites can be built faster than equivalent 3-D printed structures," he said. "Traditional manufacturing requires expensive machinery, and 3D printing is too slow for mass production, but planar composites can be rapidly built with inexpensive tools like laser cutters and etch tanks, and then folded into functional machines.
“Such manufacturing methods would be ideal for producing 100 to 1000 units."
But Felton added that the prototype robots still have some problems, though, including a propensity to burn up before they have folded into shape. "There is a great deal that we can improve based on this foundational step," said Felton.