Researchers from North Carolina State University have developed EpiPad, a technology that turns the forearm into a touchpad for smartwatches. The system uses a millimeter-wave radar to detect skin deformations caused by finger touches, gestures, and pressure.
The sensor measures approximately 5 by 4 millimeters. It utilizes machine learning algorithms to recognize gestures and analyzes radio signal phase changes to determine pressure levels. Users require a four-minute calibration process before operation.
In tests with 20 volunteers, the system achieved 92.8 percent gesture recognition accuracy and 90.2 percent accuracy for pressure detection, with a positional accuracy of 10.2 millimeters.
According to lead researcher Chenhan Xu, the components could cost less than $10 in mass production. The team plans to integrate the technology into smartwatch housings or use it for screenless devices like AI glasses.
