Scientists from MIT Media Lab’s Tangible Media Group have devised a way to three-dimensionally print hair-like structures on both flat and curved surfaces. The technique, dubbed “Cilllia,” after the cilia filaments that project from nearly all mammalian cells, involves a software platform that allows a user to design and fabricate 50-micron “hair geometries” based on predefined attributes such as angle, thickness, density, and height. Like the motile cilia and flagella found in eukaryotes, MIT’s Cilllia can be assigned sensory functions for the purpose of creating interactive textured surfaces.
“Hair is a natural responsive material that interfaces between the living organism and its environment by creating functionalities like adhesion, locomotion, and sensing,” wrote Jifei Ou, a research assistant at the lab and the lead author of a paper presented at the CHI 2016 conference in San Jose, Calif., earlier this month.
Inspired by the way hair achieves different properties by way of its unique high aspect ratio, Ou and his colleagues set out to create fine, bristle-like structures that can not only sense touch and be actuated but also manifest digital information on the physical plane.
“The ability to 3D-print hair-like structures opens up new possibilities for personal fabrication and interaction,” Ou explained. “We can quickly prototype objects with highly customized fine surface textures that have mechanical adhesion properties, or brushes with controllable stiffness and texture. A 3D-printed figure can translate vibration into a controlled motion based on the hair geometry, and printed objects can now sense human touch direction and velocity.”
There were a few roadblocks, such as the current state of computer-aided design software. The Tangible Media Group wound up developing its own bitmap-generating software to render thousands of minuscule hairs with “real geometry” that can detect, say, the direction and velocity of a swipe of someone’s finger.
The project is in its early days yet, but already Cilllia has a host of potential applications, from the mundane (objects with bristles, such as a figurine of a hedgehog) to the sublime (a table that sorts or moves objects based on their vibrational frequencies).
“As high-resolution 3D printers become increasingly available and affordable, we envision a future where physical materials’ properties, whether optical or mechanical, electrical or biological, can be encoded and decoded directly by users,” Ou added. “This allows us to customize and fabricate interactive objects as needed.”