Currently, smart garments typically rely on conductors that are placed on top of existing fabrics, and these connect sensors and controllers. To make clothing that lasts longer, feels more comfortable, and is more effective, it would be better to create the fabrics using conductive threads. It can be difficult to make these threads, however, and they often require specialized materials.
Researchers at the University of Massachusetts have come up with way to make almost any material conductive. They use vapor deposition to put thin film layers of a conductive material to a wide range of fabrics, including five different weaves of cotton, linen, and silk. The layers were about 500 nanometers, one-tenth the thickness of a human hair. The material was PEDOT, a conductive polymer that is widely used in flexible electronics and other applications. The result was flexible, resisting stretching, wearing, and repeated washing and ironing. Vapor deposition has been expensive and difficult, especially in a laboratory setting, but it has become commonplace in many industries, such as flat panel television fabrication and carpet manufacturing. As a result, it is a practical method to turn an existing garment into a smart one.
The coatings also can harvest energy from motion through triboelectric charging (which we used to call “static electricity”). The researchers are working to develop ways to connect sensors to the fabric, so you could have multiple sensors for more accurate heartbeat tracking. They even have plans to turn standard fabric into solar cells to harvest light energy to power wearables and other devices.