A few months back I covered a process developed at Carnegie Mellon University for creating self-assembling materials that can be printed on a standard 3D printer. Enabling flat sheets to take 3D form on their own could have novel applications in manufacturing and global commerce, I wrote, since flat, stackable items are optimized for shipping.
Now the researchers behind the technology are back with a kind of high tech (albeit easily produced) paper that folds and unfolds itself when a mild electric current is applied.
The result is a reusable actuator that can be used to make inexpensive robots.
Lining Yao, assistant professor in the Human-Computer Interaction Institute (HCII) and director of the Morphing Matter Lab, which studies next-gen materials, led the team that created these paper actuators.
"We are reinventing this really old material," explains Professor Yao. "Actuation truly turns paper into another medium, one that has both artistic and practical uses."
The paper actuators are created by applying a thin layer of conducting thermoplastic to plain old paper. The thermoplastic can be applied via a 3D printer or hand painted on. When current is applied, the thermoplastic heats and expands, causing the paper to bend and flex in a predetermined way. When the current is removed, the paper returns to its original shape.
"Most robots - even those that are made of paper - require an external motor," says Guanyun Wang, a CMU Manufacturing Futures Initiative fellow. "Ours do not, which creates new opportunities, not just for robotics, but for interactive art, entertainment, and home applications."
To demonstrate the artistic potential, the researchers recently gave the mechanical paper to 50 students in a workshop in China and told them to let their imaginations run wild. The students used the actuated paper to create elaborate pop-up books, as illustrated in the embedded video.
There are plausible practical uses for the technology, as well. One example would be a lamp shade that changes shape depending on the amount of light emitted.
The paper actuators will go on tour starting in September, appearing in exhibits at the Ars Electronica Festival in Linz, Austria, the Bozar Centre for the Fine Arts in Brussels, Belgium, and the Hyundai Motorstudio in Beijing, China.