Researchers from Soongsil University in Seoul have developed a flexible, waterproof sensor that can be used for submerged wearable applications, including scuba diving gear, healthcare devices, smart textiles, and more.
According to their recently published paper, the team demonstrated using the pressure sensor to control a phone, such as playing music and taking pictures, while fully immersed in water. They also incorporated the sensor into a flexible face mask, which could track the breath rate of a wearer by detecting air movement inside the mask.
"Flexible electronics will usher in a whole new world of wearable technologies to monitor our health and lifestyles," stated materials scientist Jooyong Kim. "But until now, many of these applications have been held back because the pressure sensors they rely on could not handle being exposed to water. We have changed that."
The researchers designed the sensor using a hand marker to create a circuit on a conductive material, which acts as a shield as excess material is etched away. The sensor was then mounted onto a bed of wet tissue paper and carbon nanotubes that detect changes in pressure and then covered it with tape, making it waterproof.
The sensor converts tiny movements caused by air pressure and electrical resistance into electrical signals. Machine learning algorithms were used to process those signals at up to 94% accuracy. By connecting the sensor to a wireless network, the researchers could control the phone functions mentioned earlier. It's their hope that readily available materials, easy fabrication techniques, and machine learning algorithms will help further the development of hand-drawn sensors in the next few years.