Electronic textiles hold much promise in the evolution of wearable technology. But when it comes to advances in e-textiles, engineers have the same problem as many average adults: laundry. It turns out that it’s difficult to create comfortable electronic fabrics with complex smart functions that hold up to repeated use and regular washings. Recent breakthroughs, such as the work of researchers at Fudan University in China, could help smart garments climb out of the laundry pile.
A large interactive display embedded in a smart garment would allow a user to interact directly with its features and communicate with other devices via a Bluetooth or Internet connection. However, standard display technology doesn’t translate into wearable applications; the twists and tugs of regular wear and washing cause damage or deformation that impedes functionality.
As described in a paper published in Nature, the Fudan University researchers tackled this challenge by weaving together conductive and luminescent fibers that are less than half a millimeter in diameter within a cotton fiber matrix. By weaving the luminescent yarns in the warp direction and the conductive yarns in the weft direction, the yarns’ point of contact becomes an electroluminescent unit.
The team created a prototype fabric six meters long and 25 centimeters wide with electroluminescent units spaced approximately 800 micrometers apart. Because the units are part of the weave, their structure doesn’t change as the fabric twists and bends.
Electronic yarns of different colors allow fabric to glow and change color. They can be powered by solar energy harvesters built into the textile. When integrated with sensors and a Bluetooth system, an individual can use the fabric’s touch-sensitive display keyboard to communicate with a smartphone or navigational map.
To test the device, the engineers performed 1,000 cycles of bending, stretching, and pressing. They also put the fabric through 100 machine washing and drying cycles: roughly two years’ worth of cleaning. Despite the stress of testing, the electroluminescent units’ brightness and functionality degraded less than 8%, with the vast majority of units retaining full performance.
Glowing clothing could certainly be fun, and clothing that integrates with the Internet of Things will certainly prove useful. But healthcare is where interactive smart garments could have big benefits. Clothing that helps users with voice, speech, or language difficulties communicate with devices and other people may take accessibility to new levels. That might even make laundry day feel less like a chore.