NEWS
A Knit Above
Multi-stable fabric that can hold multiple stable shapes could open the door to interactive lamps, wearables, and other responsive textiles.
Written by Claudia Hoffacker
TEXTILES ARE FLEXIBLE, CONTINUOUS MATERIALS. In their simplest form—a flat piece of cloth with no constraints—they don’t have distinct, well-defined stable states. But Harvard researchers are exploring ways of changing that, and they discovered some practical applications for multi-stable textiles.
The researchers are at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS), and their work has resulted in multi-stable knit fabrics that can be folded, shaped, and even illuminated when embedded with the proper circuitry.
Engineering Textiles
“I was learning about machine knitting and all these fabrication techniques,” said Kausalya Mahadevan, a doctoral student at SEAS who was the lead graduate researcher on this project.
“I wanted to explore the origin of curvature in textiles and think about it in a more scientific way. Textile artists have thought about it from an artistic point of view. I wanted to take these structures and try to come up with a set of rules for designing them, for understanding them, and explore them from a scientific point of view,” she explained.
Mahadevan and some of her colleagues in Professor Katia Bertoldi’s lab displayed their multi-stable knit fabrics at the Harvard ArtLab last March. The exhibition, called “Knitted Light and Responsive Textiles,” featured a variety of multi-stable fabrics, from textile lamps to wall hangings that can be pulled down to reveal text.
Doctoral student Kausalya Mahadevan with a multistable fabric at the ArtLab. Photo: Matt Goisman/SEAS
Visitors explore “Knitted Light and Responsive Textiles” at the ArtLab. Photo: Matt Goisman/SEAS
At the ArtLab exhibit, “we demonstrated a lamp that is completely made of textiles, except for the lights and wires. It’s very lightweight and incorporates soft switches, so you can transform the state and, therefore, also the lighting,” said Mahadevan, who co-authored a paper on the research.
To embed the circuitry into the fabric of the lamp, researchers incorporated a very thin conductive yarn, which allowed them to close and open a circuit, she explained. “When that’s in place, that becomes a part of a larger circuit. So, we had these different switches connected to a small ‘brain.’ This is a small circuit board that you can program on your computer, and then that brain would be able to detect when the switches were open and closed. Then that was connected to a series of LEDs, and it would tell the LEDs what color they could turn on,” she said.
Inviting Public Interaction
The development of the textile lamp inspired the idea for the ArtLab exhibition, Mahadevan added. “We wanted to invite people to come and interact with our different structures and try to learn something about those interactions,” Mahadevan said.
Before the exhibition, the researchers had to do a lot of work on the display items to make them sturdy enough to withstand multiple people handling them over the course of several hours, she said.
This involved taking the “structures from being a very simple proof-of-concept circuit” to something more robust. The team had to scale the structures up and figure out how to install the lamps and connect the circuitry. In addition, they had to determine the type of lighting that would be most effective for the exhibit.
“So, it was a lot of figuring out these engineering problems, which was new and exciting for us,” she said. “It took a fair amount of trial and error, but the exhibition turned out great. People were able to interact with them, and the structures were robust and lasted a while.”
The initial development of the multi-stable knit fabrics also required some sophisticated engineering skills. One of the strategies the researchers used was to think of these two building blocks: a rib textile and a garter textile, Mahadevan explained.
“Basically, these have perpendicular corrugations. So, in rib textile, the corrugations occur vertically, and in garter textile, the corrugations occur horizontally,” she said.
The researchers thought about how they could combine those two building blocks to create multi-stable textiles, and they came up with strategies to create textiles that can switch back and forth between the two types.
“We harness internal stresses to generate pronounced local curvatures and exploit them for functionality. By selecting specific knit patterns of front-knits and back-knits, we engineer curved morphologies, snap-through instabilities, and multi-stability into the fabric,” the researchers said in their paper.
Undergraduate researcher Anya Zhang with a multistable fabric. Photo: Matt Goisman/SEAS
Doctoral student Helen Read with a wall hanging. Photo: Matt Goisman/SEAS
Other Uses
In addition to the fabric lamp, another potential application of the research is a wearable device for cyclists that would incorporate haptic feedback.
“For example, when you’re driving, you don’t need to look at your turn signals or your wipers because there is that switch behavior, where you feel that you’ve snapped the switch from one state to the other,” Mahadevan said. “In our textiles, we’re also able to feel this. We’ve built and demonstrated a sleeve that can be used while cycling. This device provides haptic feedback while allowing a cyclist to use established hand signals.”
Mahadevan said she enjoys thinking about textiles in new ways, and she’s excited to continue her research.
“I wanted to think about textiles in a similar way to how a lot of mechanical engineers have been thinking about other structures, like polymer-based structures, for a while,” she said. “Multi-stabilities occur, especially in light switches or other switches that we interact with. They’re all around us, but less so in textiles and other soft materials. That’s what makes this research interesting.”
Claudia Hoffacker is an independent writer in Minneapolis.
© 2026 The American Society of Mechanical Engineers. All rights reserved.