"Amphibious" sensors enable the development of innovative waterproof technologies.

Researchers have developed a method for creating sensors that can operate both in air and underwater, paving the way for "amphibious" sensors with potential applications ranging from wildlife monitoring to biomedical uses.

The research focuses on strain sensors, which measure deformation, allowing them to track stretching, bending, and movement.

"For instance, there is interest in developing strain sensors for biomedical purposes, such as monitoring the behavior of blood vessels and other biological systems," says Shuang Wu, the lead author of the study and a postdoctoral researcher at North Carolina State University. "Other potential applications include tracking how fish move underwater and monitoring wildlife health." However, a significant challenge in designing wearable or implantable strain sensors is ensuring they function effectively in wet environments, notes Yong Zhu, the corresponding author and Andrew A. Adams Distinguished Professor of Mechanical and Aerospace Engineering at NC State.

"Our aim with this work was to create sensors that could endure prolonged exposure to wet environments without compromising their performance," Wu explains.

To achieve this, the research team started with a highly sensitive strain sensor they had developed in late 2022. They then encapsulated the sensor between two thin films made from a highly elastic, waterproof polymer.

This polymer coating protects the sensor from water intrusion while maintaining the sensor's movement and sensitivity, unlike most other encapsulation methods. The sensor remains both sensitive and stretchable and can be connected to a small chip for wireless data transmission.

"In our experiments, the amphibious sensors proved to be highly sensitive with a quick response time," says Wu. "We also found that the sensors performed equally well in air and after being submerged in saltwater for 20 days."

"The sensors are incredibly durable, maintaining their performance even after being stretched 16,000 times," adds Zhu.

To showcase the capabilities of the amphibious sensors, the researchers used them to track the movements of robotic fish and monitor blood pressure in a pig's heart. They also created a glove embedded with the sensors, which could translate a scuba diver's hand signals into messages readable by people both in and out of the water. "The idea was to develop an easy way for scuba divers to communicate effectively with other divers underwater or with crew members on a boat," Wu explains.

"We have submitted a patent application for this technology and are open to collaborating with industry partners to integrate these sensors into various applications," says Zhu.

This research was supported by grants from the National Science Foundation (2122841 and 2134664), the National Institutes of Health (R01HD108473), and the Department of Defense (W81XWH-21-1-0185).

Original Source: https://www.sciencedaily.com/releases/2024/08/240807122739.htm