Northwestern University engineers develop battery-free smart glasses

Engineers at Northwestern University have developed GlassTENG, a prototype for battery-free smart glasses that harvests energy from natural facial movements to power health-monitoring sensors.

The system utilizes triboelectric nanogenerators (TENGs) to convert mechanical energy from contact and separation between materials—similar to static electricity—into electrical charges. By embedding flexible sensors into an ordinary glasses frame, the device can track various physiological and behavioral signals without the need for recharging.

Three specific sensors are positioned on the frame to monitor different activities: • A nose bridge sensor detects pulse signals, blinking, and eyebrow movements. • A temple sensor monitors pulse and jaw activity. • An ear-adjacent sensor detects chewing and teeth clenching.

In testing with 20 volunteers, a machine-learning algorithm identified performed activities with 93.8% accuracy. The technology aims to provide continuous, passive health monitoring for conditions such as bruxism, fatigue, and cardiovascular signals by integrating clinical-grade sensing into everyday eyewear.