Sensors in Your Clothes Are Nearly Ready to Replace Mobile Devices

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Researchers from the University of Tokyo have developed a new way for consumers to interact with textiles. The team was led by professor Takao Someya; they demonstrate in their paper how this ink tech was able to function (even when stretched up to three times its original length) as a sensor to measure heart rate, muscle contractions, and a number of other biological indicators — all in your shirt.

Until recently, transistors have only been able to be printed on plastic or paper substrates. But as past studies have shown, wearable bands often cease to be used after a month of use. Putting on a T-shirt that can double as a fitness monitor, however, doesn’t detract from the routine.

Someya said:

“Our team aims to develop comfortable wearable devices. This ink was developed as part of this endeavor.”

Someya and his team claim they have developed an elastic conducting ink that’s easily printed onto clothing — a big achievement for the future of wearable devices. They write in their paper that the ink is “comprised of [silver] flakes, a fluorine rubber and a fluorine surfactant. The fluorine surfactant constitutes a key component which directs the formation of surface-localized conductive networks in the printed elastic conductor, leading to a high conductivity and stretchability.”

Someya added:

“The biggest challenge was obtaining high conductivity and stretchability with a simple one-step printing process. We were able to achieve this by use of a surfactant that allowed the silver flakes to self-assemble at the surface of the printed pattern, ensuring high conductivity.”

The team demonstrated the application of this conductive ink by printing a wrist-worn muscle sensor (seen above). The sensor was created by printing one on both sides of the cloth.

Google recently demoed its own take on the future of wearable fabrics at its I/O event, dubbed Project Jacquard. The future of wearables is looking interesting; the question is who will be first to market. Singularity University’s Vivek Wadhwa may have an idea; he details the tech innovations he’s most interested in — including some exciting new wearables: