New patch detects muscle movement through the skin via nanomagnets
Marie Donlon | July 17, 2023Researchers from the University of California, Los Angeles have developed a smart textile composed of conductive yarn and nanomagnet composites that is capable of sensing and measuring body movements — including veins pulsating or muscles flexing.
The smart textile, which features a cloth-like texture, is reportedly comprised of a nanomagnet-filled rubber patch that is about the size of two stamps. The researchers stitched silver-coated conductive yarn, using a sewing machine, onto the patch in a coil design.
Source: Jun Chen/University of California, Los Angeles
According to the research team, mechanical forces, like a finger tap, deformed the pattern of magnetic fields contained within the rubber, thereby forcing an electric current through the yarn. Such phenomena, wherein forces alter both the magnetic fields and magnetic flux variations, reportedly produced electricity known as the magnetoelastic effect and electromagnetic induction.
"Our device is very sensitive to biomechanical pressure," the researchers explained. "The device converts muscle activities into quantifiable, high-fidelity electrical signals that are sent wirelessly to phone apps. This demonstrates the potential for personalized physical therapies and improving the rehabilitation of muscle injuries."
The researchers suggest that the device — in addition to being sensitive — is also precise and is capable of detailing body movements down to the specific muscle group. As such, the team attached the device to various body parts and measured the throat movements of the wearer as they drank fluids, their ankle movements as they walked and monitored the wearer’s pulse from their wrist.
Further, the team demonstrated that the device can be attached to the wearer’s bicep and reveal if they are bending their arm or gripping their fist and to what degree or force. Such data can inform clinician decisions about patient exertion and potentially serve to encourage moderate activities, while customizing recovery goals for patients.
The device is also self-powered and can convert biomechanical force to electricity, thereby eliminating the need for bulky, heavy and rigid battery packs.
An article detailing the device, A textile magnetoelastic patch for self-powered personalized muscle physiotherapy, appears in the journal Matter.
For more information on the patch, watch the accompanying video that appears courtesy of Jun Chen from the University of California, Los Angeles.