Engineering news
A real-life Transformer has been created by US scientists inspired by the Japanese paper-folding art of origami.
Harvard University scientists built the self-assembling four-legged robot from nothing more than sheets of paper and shape-memory plastic also known as Shrinky dinks™ – the classic children's toy that shrinks when heated - containing embedded electronics.
In tests, the small shape-changing robot folded itself into a functional machine that could walk and turn without human help.
Once connected to a battery power supply, the flat composite heated up, folded, and transformed into a mobile robot in about four minutes.
The 5in (12.7cm) long device crawled away at a speed of more than 2in (5cm) per second and was also able to turn without assistance.
Professor Rob Wood, who led the Harvard University team, said: "Getting a robot to assemble itself autonomously and actually perform a function has been a milestone we've been chasing for many years.
"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 self-folding process involves hinges that are programmed to fold at specific angles. Each hinge contains embedded circuits that produce heat on command from the microcontroller. The heat triggers the composite to self-fold in a series of steps.
When the hinges cool after about four minutes, the plastic hardens — making the robot stiff — and the microncontroller then signals the robot to crawl away at a speed of about one-tenth of a mile per hour. The entire event consumed about the same amount of energy in one AA alkaline battery.
Experts believe the assembly system could provide a cheap way to mass-produce robots with multiple applications.
They may be especially useful for accessing confined spaces, for instance when searching for survivors in collapsed buildings. A "flat pack" robot could be posted through a narrow gap or tunnel before expanding itself to full-size.
Sam Felton, part of the Harvard University team, pointed out that traditional manufacturing required costly machinery and 3D printing was too slow for mass production. But the components of folding robots could be produced rapidly and cheaply using standard tools such as laser cutters and printed circuit etching technology.
"Such manufacturing methods would be ideal for producing 100-1000 units," said Mr Felton, a doctoral student at Harvard. "These robots are inexpensive and their layered composites can be built faster than equivalent 3D printed structures."
A software program called "Origamizer" was used to generate the crease patterns at the heart of the automated folding process, the researchers reported in the journal Science.
Other potential applications for the technology included its use in space exploration, self-folding shelters, and Ikea-style furniture that can assemble itself.