Pants made with electronic yarn could transmit exhaustion alerts

Most of us don't really need to wear special pants that let us know when we're exhausted; we're good at figuring that out all on our own. However, when it comes to hardcore athletes, getting an alert when the body starts moving in a way that indicates physical exhaustion could be a good thing. To that end, researchers have developed an electronic yarn that could be used to detect shifts in movement patterns, and alert wearers that it's time to take a break.

The yarn was developed by researchers at the Swiss Federal Institute of Technology in Zurich (ETH Zurich), and it consists of an inner cord made from stretchable conductive rubber surrounded in a spiral pattern by a rigid wire covered in a thin layer of plastic.

"These two fibers act as electrodes and create an electric field," said Tyler Cuthbert, an ETH Zurich postdoc student who participated in the research that led to the fiber. "Together, they form a capacitor that can hold an electric charge."

What this means is that if the fiber is built into a pair of pants (for example), as the wearer moves, the gap between the flexible inner core and rigid outer rigid portion will vary. This will create a difference between the two, which will in turn alter the electric field produced by the yarn. Helping this process along is the fact that the yarn itself actually expands when stretched, so it provides more of a surface area from which to take readings.

By tracking the alterations in current with a monitoring device that would also be sewn into the garment, the researchers say that they can accurately track movement patterns and know when the wearer is beginning to reach the point of exhaustion. The monitoring device would be equipped with a tiny antenna that could beam information to a smartphone, alerting exercisers that they were reaching a state of fatigue during which they would be more prone to injuries.

The research team has already gathered some data showing how the yarn's electrical signals changed as runners reached exhaustion, but they say more testing is required to build a database of reliable gait patterns so that the material will work as accurately as possible. Still, they've already applied for a patent for the system, and are currently working to move from prototype to a fabric embedded with the yarn that would be ready for consumers.

While many sports wearables focus on providing the user with data related to improving performance, this new material joins a slightly different category that seeks to keep athletes safe such as T-shirts and sports bras that alert wearers to an impending heart attack. Carlo Menon, Professor of Mobile Health Technology and lead researcher, says the material could find a home in rehabilitation medicine as well.

The work has been published in the peer-reviewed journal, Advanced Materials.

Source: ETH Zurich