Material That Transforms Instantly with a Simple Pull

Highlights

• Material Science: Researchers developed an innovative material that transforms from a flat grid to a 3D structure with a single string pull.
• Applications: This new material has potential uses in medical devices, foldable robots, and modular habitats for space exploration.
• Algorithm: The team created a specialized algorithm that converts 3D designs into a flat pattern, optimizing the transformation process.
• Real-world Objects: The technique has been successfully applied to design functional items, including a human-sized chair.

There’s a very thin line between math and art. As it turns out, the same can be said about material science and paper art.

At first glance, the flat, tiled pattern developed by researchers doesn’t look too special. But once you pull the little string sticking out from the side, the grid quickly transforms into, well, any 3D structure it’s meant to be. The new material, inspired by the Japanese paper art technique known as kirigami, could have an impressive range of applications, from transportable medical devices and foldable robots to modular space habitats on Mars.

The researchers, led by MIT’s Computer Science and Artificial Intelligence Laboratory, describe the new material in a recent ACM Transactions on Graphics paper.

Art-inspired algorithm

For the new material, the researchers developed an algorithm that translates the 3D structure provided by users into a flat grid of quadrilateral tiles. This mimics how artists that practice kirigami (literally Japanese for “cutting paper”) cut material in certain ways to “encode it with unique properties,” the researchers explained to MIT News.

The specific mechanism applied here is known as an auxetic mechanism, which refers to a structure that grows thicker when stretched out but thinner when compressed.

The algorithm then calculates the “optimal string path” to minimize friction and connect the lift points along the surface, so the grids become the intended 3D structure with one smooth pull of a string.

“The simplicity of the whole actuation mechanism is a real benefit of our approach,” Akib Zaman, the study’s lead author and a graduate student at MIT, told MIT News. “All they have to do is input their design, and our algorithm automatically takes care of the rest.”

The chair that held

After multiple simulations, the team finally used their method to design several real-life objects. These included medical tools such as splints or posture correctors and igloo-like structures.

What’s more, the algorithm is “agnostic to the fabrication method,” so the researchers used laser-cut plywood boxes to create a fully deployable, human-sized chair—and it held when used as an actual chair, according to the paper.

That said, there will likely be “scale-specific engineering challenges” for larger architectural structures, the researchers noted in the paper. But the novel method is easy to use and relatively accessible, so the team is now enthusiastically exploring ways to tackle these challenges, in addition to building tinier structures with this technique.

“I hope people will be able to use this method to create a wide variety of different, deployable structures,” Zaman said.