This self-folding robot goes from flat to fast (sort of) in just four minutes. Using flat materials and origami-inspired patterns, researchers have designed a real-life transformer that can assemble itself, then walk and even turn around on its own. The work was published in Science this week.
Robots that can be shipped flat in large quantities and self-organize without our help would be super useful for various types of work: from exploration to search-and-rescue missions in confined spaces. Until now, no self-folding approach has yielded a machine that functions without additional outside assistance. To create the first robot that builds itself without human intervention, Harvard’s Sam Felton and colleagues went through about 40 prototypes made of paper-flat plastics embedded with electronics and motors sitting on top.
The clear, shape-memory polymer -- the kind used in Shrinky Dinks -- contracts when heated to 100 degrees Celsius; this makes up the outer layers. The middle layer is copper, etched into a network of electrical leads, and that’s sandwiched between two structural layers of paper. All five layers are cut according to digital specifications by a laser cutter, and they have self-folding hinges, as well as a pre-determined order in which to fold. A microcontroller, two batteries, and small motors are attached to the top. Once triggered by the embedded heat-generating circuits (as commanded by the microcontroller), the flat sheets become complex 3D machines.
Here’s another view of the robot in three stages. You can see the detailed crease patterns in the polymer generated by 3D origami design software Origamizer. “The exciting thing here is that you create this device that has computation embedded in the flat, printed version,” Daniela Rus of MIT says in a university release. “And when these devices lift up from the ground into the third dimension, they do it in a thoughtful way.”
After the robot folds itself up -- in just four minutes -- the motor engages and it crawls off at a speed of 5.4 centimeters per second (that’s one-tenth of a mile per hour).
"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," Harvard’s Rob Wood explains in a news release. These are all easy-to-find materials put together with inexpensive tools -- ideal for producing up to 1,000 units. Each robot costs about $100, but only $20 for just the body without motors, batteries, or microcontrollers.
"The days of big, rigid, robots that sit in place and carry out the same repetitive task day in and out are fading fast,” Harvard’s Don Ingber says in a university statement. Robots that ship flat and self-assemble onsite would be incredibly valuable for deployment in collapsed buildings, small tunnels, or disaster zones. The technology could also help with rapid prototyping of tiny machines too small to be assembled by hand.
The team describes their very cool process in this video. The robot folds itself and crawls away starting around 1:00.
Images: Seth Kroll, Wyss Institute
Video: Wyss Institute for Biologically Inspired Engineering at Harvard University