According to North Carolina State University, researchers have developed wearable, multifunctional sensors that may hold promise in a range of applications, including new prosthetics, robotic systems, and flexible touch panels. Researchers reportedly used silver nanowires to develop the sensors, which are designed to measure strain, pressure, human touch, and bioelectronics signals such as electrocardiograms.
In a news release from the university, Shanshan Yao, PhD student, North Carolina State University, lead author, states that the technology hinges on either physical deformation or “fringing” electric field changes.
“The latter is very similar to the mechanism used in smartphone touch screens, but the sensors we’ve developed are stretchable and can be mounted on a variety of curvilinear surfaces such as human skin,” Yao explains.
Young Zhu, PhD, associate professor mechanical and aerospace engineering at North Carolina State, senior author, adds that the sensor could potentially be used to develop prosthetics engineered to respond to a user’s movement and provide feedback when in use.
The sensors could also hold implications in robotics, and could be “incorporated into clothing to track motion or monitor an individual’s physical health,” Zhu says.
The release states that the researchers based the current study on Zhu’s previous work, which aimed to create highly conductive and elastic conductors built from silver nanowires. Researchers reportedly placed an insulating material between two of the stretchable conductors. The two layers, researchers say, then have the “capacitance” to store electric charges. The pushing, pulling, or touching of the stretchable conductors modifies the capacitance. Researchers state that the sensors then measure the change in capacitance.
The researchers have already tested the sensors in prototype applications, the release notes, including using them to monitor thumb movement. The researchers also demonstrated an application to monitor knee movements while a test subject ran, walked, and jumped.
“…Our sensors can be stretched to 150% or more of their original length without losing functionality,” Zhu points out.
The researchers add that they have developed a variety of sensors designed to map pressure distribution, which exhibit a 40-millisecond response time to allow strain and pressure to be monitored in real time.
[Photo Credit: North Carolina State University]
[Source: North Carolina State University]