The Purdue Frederick Co., Inc.

Purdue University engineers are touting a method for turning cloth items into battery-free, wearable and wireless “smart clothes.” The engineers at the West Lafayette, Ind.–based university developed a new spray/sewing method designed to transform any conventional cloth item into these smart clothes that can also be cleaned in the washing machine like normal clothing. “By spray-coating smart clothes with highly hydrophobic molecules, we are able to render them repellent to water, oil and mud,” Purdue School of Industrial Engineering/Weldon School of Biomedical Engineering assistant professor Ramses Martinez said in a news release. “These smart clothes are almost impossible to stain and can be used underwater and washed in conventional washing machines without damaging the electronic components sewn on their surface.” Typically, waterproof garments have a rigidity and a reduced breathability that make them uncomfortable after being worn for a few hours, the researchers say, but, with an ultrathin coating, the smart clothes they’ve developed remain as flexible, stretchable and breathable as standard cotton t-shirts, Martinez claims. Additionally, the clothes do not require batteries for power, instead harvesting energy from Wi-Fi or radio waves in the environment to power the circuitry sewn onto the textile. The researchers gave an example of a battery-free glove that illuminates its fingertips every time the user is near a live cable, warning about the potential for an electric shock. Another possibility is a miniaturized cardiac monitoring system sewn onto a washable sweatband, offering health monitoring for the wearer. According to the researchers, the technology can be fabricated in conventional, large-scale sewing facilities to accelerate the development and commercialization of smart clothes. “Such wearable devices, powered by ubiquitous Wi-Fi signals, will make us not only think of clothing as just a garment that keeps us warm but also as wearable tools designed to help us in our daily life, monitor our health and protect us from accidents,” Martinez said. “I envision smart clothes will be able to transmit information about the posture and motion of the wearer to mobile apps, allowing machines to understand human intent without the need of other interfaces, expanding the way we communicate, interact with devices, and play video games.”