Zhengyu Li, Xingyu Chen, Liye Zhao, Jiawen Xu
Triboelectric nanogenerator-based vibration sensors offer a promising solution for large-scale, distributed vibration monitoring in mechanical equipment and civil infrastructure. However, their performance is often compromised by inherent structural resonance, which introduces frequency-dependent sensitivity and distorts broadband vibration waveforms. In this work, we present a quasi-zero stiffness triboelectric vibration sensor (QZS-TEVS) that extends the post-resonance operational region towards ultralow frequencies, facilitating high-fidelity broadband vibration characterization. Specifically, an ultralow resonant frequency is realized via the QZS characteristic of the tailored harmonic curved beam. This strategic resonance shift broadens the flat-response bandwidth, thereby effectively suppressing resonance-induced distortion. The QZS-TEVS exhibits a nearly constant displacement sensitivity of 0.31 V/μm over 10-300 Hz, with a frequency measurement accuracy of 99.98%. Furthermore, the QZS-TEVS achieves precise reconstruction of arbitrary vibration waveforms. This work shifts the design paradigm from resonance-driven energy maximization to high-fidelity characterization and provides a high-precision scheme for self-powered, multidimensional condition monitoring within the Industrial Internet of Things (IIoT).