These sensors maintain high performance and durability in wet environments, offering potential advancements in tracking fish movements, monitoring blood pressure, and improving scuba diver communication.
Researchers have developed sensors in both air and underwater, potentially useful for wildlife monitoring and biomedical applications. These strain sensors measure deformation, making them suitable for monitoring stretching, bending, and movement. The researchers at North Carolina State University, notes the interest in strain sensors for biomedical uses, such as observing blood vessel behavior. Other applications include monitoring fish movement underwater and wildlife health. According to Yong Zhu, the corresponding author of the paper and the Andrew A. Adams Distinguished Professor of Mechanical and Aerospace Engineering at NC State, a significant challenge in creating wearable or implantable strain sensors is ensuring they perform in wet environments. The goal was to create sensors that last long in wet environments without compromising performance.
The research team started with a sensitive strain sensor developed in late 2022. They then encapsulated the sensor between two thin films of a highly elastic, waterproof polymer. This polymer keeps water out but does not restrict the sensor’s movement due to its unique interface design, maintaining sensitivity and stretchability. The sensor connects to a small chip that transmits data wirelessly. In experiments, the amphibious sensors demonstrated sensitivity and fast response times. The performance remained consistent whether the sensor was in air or submerged in saltwater for 20 days. The sensors also showed stability, with performance unaffected even after being stretched 16,000 times.
To demonstrate functionality, the researchers tracked the motions of robotic fish and monitored blood pressure in a pig’s heart using the sensors. They also created a glove with the sensors, translating a scuba diver’s hand signals into readable messages for people in and out of the water. This aims to improve underwater communication for divers. The researchers have submitted a patent application for this technology and are open to industry partnerships for various applications.
