MIT programmable fiber can infer physical activity

Researchers at MIT have created the first fiber that has digital capabilities. The fiber can sense, store, analyze, and infer activity and be sewn into his shirt. MIT professor Yoel Fink says the digital fiber has expanded the possibilities for fabrics to uncover hidden patterns in the human body that could potentially be used for physical performance monitoring, medical inference, and early disease detection.

Until the MIT breakthrough, electronic fibers have been analog, carrying a continuous electric signal rather than digital where bits of information can be encoded and processed within the fiber. The new work is the first realization of a fabric with the ability to store and process data digitally. Fink says the new fiber allows fabrics to be programmed.

Researchers created the fiber by placing hundreds of square silicon microscale digital chips into a preform to create a polymer fiber. By controlling the polymer flow precisely, the researchers created a fiber providing a continuous electrical connection between the chips over tens of meters. The resulting fiber is thin and flexible, allowing it to be passed through a needle to be sewn into fabrics.

The digital fibers are also robust and can be washed at least ten times without breaking down. The fiber is also thin enough and comfortable enough that it can't be felt by the wearer when woven into a shirt. Data storage is also possible within the fiber. The researchers can write, store, and read information on the fiber, including a 767-kilobit full-color movie file and a 0.48-megabyte music file. Files can be stored within the fiber for up to two months without power.

The new fiber also has potential for medical use and, in testing, was integrated into the armpit of a shirt and used to collect 270 minutes of surface body temperature data. The team confirmed with 96 percent accuracy what activity the person wearing the shirt was engaged in when it was recorded. A small external device currently controls the fiber, and researchers are designing a new chip as a microcontroller that can be connected within the fiber.