GlassTENG: Self-Powered Triboelectric Nanogenerator based Sensing of Pulse, Jaw, and Upper Facial Activity from Everyday Glasses

2026-07-07

AI Summary

This study addresses the limitations of conventional smart glasses—namely, reliance on batteries and the use of gels or adhesives that cause discomfort during prolonged wear—by introducing a self-powered sensing platform integrated into standard eyeglass frames. For the first time, triboelectric nanogenerators (TENGs) are embedded at the nose bridge, temples, and temples’ distal ends to simultaneously capture angular artery pulse, temporalis muscle activity, and superficial temporal artery signals, eliminating the need for external power sources or skin-contacting media. Coupled with an ultra-low-power analog front-end circuit consuming only 1.36 μW per sensor, the system enables continuous, multimodal physiological monitoring during everyday use. In experiments with 20 participants, the system achieved 93.8% accuracy in classifying six types of jaw and facial movements and demonstrated a mean absolute error of 1.82 BPM in heart rate estimation against a chest-strap reference over 30-second intervals.

Abstract

Smart glasses maintain near-continuous skin contact at multiple arterial and muscular sites, making them a promising platform for physiological sensing. In practice, though, two factors make sustained daily wear and longitudinal deployment impractical for the quantified self: the discomfort of prolonged sensor-skin contact (e.g., gels and adhesives) and the sensor power demands that increase battery size, weight, and maintenance burden. We present GlassTENG, an ultra-low-power sensor that embeds three custom-fabricated triboelectric nanogenerators (TENGs) into a glasses frame at the angular artery on the nasal bridge, the superficial temporal artery on an extended arm, and the temporalis muscle at the temple. Each GlassTENG sensor is self-powered in transducing mechanical energy to electrical energy and consumes 1.36 $μ$W per sensor at the analog front-end. GlassTENG enables simultaneous capture of arterial pulse waveforms, jaw kinematics (e.g., clenching, tapping, eating), and upper facial activity (e.g., blinking, eyebrow movement). In a 20-participant user study, we achieve 93.8% accuracy across six jaw and upper facial activities and estimate heart rate with a mean absolute error of 1.82 beats per minute (BPM) relative to a ground-truth chest-strap sensor in 30s windows. Together, these results establish a future pathway toward a longitudinally worn, ultra-low-power, glasses-based physiological monitoring platform.

Problem

• smart glasses
• physiological sensing
• wearable discomfort
• sensor power consumption
• longitudinal monitoring

Innovation

• Triboelectric Nanogenerator
• Self-powered Sensing
• Smart Glasses
• Physiological Monitoring
• Ultra-low-power