Harvesting low-frequency micro-vibrations at sub-millimeter scales remains a significant challenge for triboelectric vibration energy harvesters (TVEHs). This work presents a displacement-amplified triboelectric vibration energy harvester (DA-TVEH) that employs a compliant mechanism to convert and amplify small vertical vibrations into enlarged radial deformations. This design enables complete contact–separation cycles at sub-millimeters, producing harmonic voltage waveforms with negligible impact noise. The DA-TVEH allows structural tunability via two geometric parameters, i.e., the bridge beam angle (α) and sweeping angle (β), which jointly control stiffness and amplification behavior. In addition, the payload serves dual roles by simultaneously tuning both the amplification ratio and the initial contact state of the triboelectric layers for enhanced efficiency. Beyond energy harvesting, the DA-TVEH successfully powered a customized wireless sensing node with an analog-to-digital converter (ADC) sampling rate of 400 Hz, supporting high-fidelity vibration acquisition. Fully battery-free wireless sensing was achieved, with cold-start and warm-start times of 160 s and 68 s, respectively. Reliable time-domain vibration signal transmission was demonstrated in shaker tests and further confirmed in a field test on a ship diesel engine. These results establish the DA-TVEH as an ultra-low-noise, fully autonomous energy harvester suited for practical self-powered sensing and continuous vibration monitoring in low-frequency environments. • Compliant mechanism enables effective micro-vibrations harvesting with low noise. • Submillimeter vibrations generate quasi-harmonic voltage output ~300 V. • Achieved broad bandwidth of 17.5 Hz in low-frequency range. • High power output supports 400 Hz ADC sampling rate. • Fully self-powered vibration sensing validated in both laboratory and field tests
Zhao et al. (Fri,) studied this question.