In the realm of wearable technology, many fitness trackers face limitations when it comes to underwater use due to the need for thick, impermeable coatings that can make them uncomfortable. However, a breakthrough has been made by researchers who have developed a breathable underwater movement sensor using a thin, slippery coating on conductive fabric. This innovation has been integrated into a smart device capable of wirelessly alerting a smartphone app if a swimmer ceases movement, potentially indicating a drowning risk.
Underwater movement sensors hold significant potential for various applications, including monitoring heart rates and ensuring swimmer safety. Traditional methods of protecting these electronics often result in bulky, air-impermeable devices that can cause skin irritation. Previous studies have demonstrated that polydimethylsiloxane (PDMS) can provide effective water resistance for flexible sensors, but its comfort level remained uncertain. Researchers aimed to explore PDMS as a water-repellent coating for a fabric-based sensor within a wireless underwater movement detection system.
The research team embarked on this project by immersing polyester knit fabric in a graphene oxide solution, followed by hydroiodic acid, and finally a solution containing PDMS microparticles and nanoparticles. Initial evaluations revealed that the coated fabric maintained conductivity and water repellency while allowing air permeability, indicating potential comfort for wearers. When tested, the fabric produced a measurable electrical response when attached to a finger bending underwater.
Revolutionary Smart Underwater Movement System
Building on this foundation, the researchers developed a smart underwater movement system by combining the fabric-based sensor with a power source and data collector. This system can wirelessly transmit electrical responses to a smartphone app. In practical tests, the smart device was affixed to a motorized swimming doll, enabling the app to track the doll's leg movements. To simulate a swimmer in distress, the doll's kicking was halted, prompting the app to issue a red alert. The researchers assert that the water-repellent smart movement sensor could enhance swimmer safety and be adapted for other underwater sensor applications.