By Becky Ham | MIT News correspondent
MIT researchers have created the first fiber with digital properties that can sense, record, analyze, and infer activity when sewn into a shirt.
Yoel Fink, a professor of materials science and electrical engineering, a leading researcher in the electronics research laboratory and a senior author of research, says digital fibers expand the possibilities for fabrics to reveal the context of hidden patterns in the human body that could be used for physical performance monitoring, medical reasoning and early detection.
Or you can sometimes record your wedding music for the dress you used on the big day – more on that later.
Fink and his colleagues describe the properties of digital fiber Nature communication. So far, electronic fibers have been analog – carrying a continuous electrical signal – rather than digital, allowing separate data bits to be encoded and processed in 0 and 1 seconds.
“This work introduces the first implementation of a fabric that is capable of storing and processing data digitally, adding a new dimension of information content to textiles, and allowing fabrics to be literally programmed,” Fink says.
Gabriel Loke, a doctoral student at MIT, and Tural Khudiyev, a postdoctor at MIT, are the main authors of the paper. Other authors MIT postdoc Wei Yan; MIT students Brian Wang, Stephanie Fu, Ioannis Chatziveroglou, Syamantak Payra, Yorai Shaoul, Johnny Fung and Itamar Chinn; John Joannopoulos, Francis Wright Davis Professor of Physics and Director of the MIT Military Institute of Nanotechnology; Pin-Wen Chou, a master’s student at Harrisburg University of Technology; and Anna Gitelson-Kahn, an assistant professor at the Rhode Island School of Design. The fabric work was facilitated by Professor Anais Missakian, who holds the textile role of RISD’s Pevaroff-Cohn family.
Memory and more
The new fiber was created by placing hundreds of square silicon microscopic digital chips in a preform, which was then used to create the polymer fiber. By precisely controlling the polymer flow, the researchers were able to create a fiber with a continuous electrical connection between the chips over a length of tens of meters.
The fiber itself is thin and flexible, and can be passed through a needle, sewn into fabrics, and washed at least 10 times without breaking. Loke says, “When you put it on a shirt, you can’t feel it at all. You don’t know it was there.”
Making a digital fiber “opens up a variety of possibilities and solves some of the problems with functional fibers,” he says.
For example, it provides a way to control individual elements within a fiber from a single point at the end of the fiber. “You can think of fiber as a hallway, and the elements are like rooms, and they all have their own unique digital room numbers,” Loke explains. The research team developed a digital addressing method that allows them to “turn on” the functionality of a single element without turning on all the elements.
A digital fiber can also store a lot of information in memory. The researchers were able to write, store, and read data from the fiber, including a 767-KB full-color short movie file and a 0.48-megabyte music file. Files can be stored for two months without power.
When they dreamed of “crazy ideas” for fiber, Loke says they were thinking of applications like a wedding dress that would store digital wedding music in their tissue tissue, or even wrote a story about creating fiber in its components.
Fink notes that MIT’s research worked closely with the Missisian-led RISD textile division. Gitelson-Kahn incorporated digital fibers into a knitted garment sleeve, paving the way for the creation of the first digital garment.
Artificial intelligence of the body
Fiber also takes a few steps forward in artificial intelligence by including in the fiber memory a 1650 connection to the neural network. By sewing it on the shirt’s armpit, the researchers collected the fiber for 270 minutes to collect body temperature data from the shirt wearer and analyzed how that data corresponded to different physical activities. Based on this information, the fiber was able to determine with 96% accuracy the activity for which the person using it was engaged.
Adding an artificial intelligence component to a fiber further increases its potential, the researchers say. Fabrics with digital components can gather a lot of information about the body over time, and this “lush information” fits perfectly into machine learning algorithms, Loke says.
“This type of fabric could provide quantitative and high-quality open source data to get new body models we didn’t know before,” he says.
With this analytical power, fibers can sometimes detect and warn people in real time of health changes, such as impaired breathing or irregular heartbeats, or provide muscle activation or heart rate information to athletes during training.
The fiber is controlled by a small external device, so the next step is to design a new chip as a microcontroller that can be connected inside the fiber itself.
“When we can do that, we can call it a fiber computer,” Loke says.
This study was supported by the U.S. Army Military Institute of Nanotechnology, the National Science Foundation, the U.S. Army Research Agency, the MIT Marine Grant, and the Defense Threat Reduction Agency.