Batteryless wearable systems that exploit the triboelectric mechanism simultaneously for sensing and energy harvesting — enabling human activity recognition, gait analysis, and rehabilitation monitoring without any external power supply.
Conventional wearable sensors — accelerometers, pressure sensors, EMG electrodes — require a battery or continuous power source. The triboelectric mechanism offers an elegant alternative: the same charge generation that produces harvestable energy also encodes a signal proportional to the motion that caused it. This enables batteryless wearable IoT nodes where a single triboelectric element serves as both sensor and power source.
The high output voltage (>20 V peak-to-peak) at low human-motion frequencies (1–10 Hz) makes triboelectric devices especially suited for this application — the signal is measurable without amplification in many cases, reducing system complexity further.
Dual-function principle: The triboelectric structure generates a self-powered motion signal from physical activities and simultaneously harvests energy, providing sustainable power for wireless data transmission in the wearable IoT node — advancing maintenance-free, autonomous health monitoring systems with zero battery replacements.
The self-powered sensing paradigm was validated across two complementary deployment scenarios:
Body-worn triboelectric sensors classify five daily activities — sitting/standing, walking, stair climbing up/down, and running — using kNN clustering on signal features, with no external power supply or signal conditioning circuits.
Four triboelectric elements embedded in shoe soles capture ground contact force (GCF) patterns and gait timing parameters, enabling clinical-grade gait analysis for rehabilitation patients during daily life.
The same tribo-elements output both a sensing signal and harvestable charge. TriboWalk generates >20 V during walking, enabling the sensor node to be partially or fully self-powered during operation.
Motion data is collected by a 10-bit ADC and transmitted wirelessly. The system architecture exploits the self-powered capability to minimize total node power consumption and extend deployment lifetime.