A Highly Sensitive Triboelectric Quasi‐Zero Stiffness Vibration Sensor with Ultrawide Frequency Response

Sensors based on triboelectric nanogenerators (TENGs) have gained worldwide interest owing to their advantages of low cost and self‐powering. However, the detection of most triboelectric vibration sensors (TVS) is restricted to low frequency, whereas high‐frequency vibration signals are successfully measured in recent studies; their sensitivity still requires improvement. Hence, a highly sensitive vibration sensor based on TENG (HSVS‐TENG) with ultrawide frequency response is presented. This study is the first to introduce a quasi‐zero stiffness structure into the TENG to minimize the driving force by optimizing the magnetic induction intensity and the weight of the moving part. The results show that the HSVS‐TENG can measure vibrations with frequencies ranging from 2.5 to 4000 Hz, with a sensitivity ranging from 0.32 to 134.9 V g(−1). Moreover, the sensor exhibits a good linear response versus the applied acceleration, and the linearity ranges from 0.08 to 2.81 V g(−1). The self‐powered sensor can monitor the running state and fault type of the key components with a recognition accuracy of 98.9% by leveraging machine‐learning algorithms. The results reach a new height for the ultrawide frequency response and high sensitivity of the TVS and provide an idea for a follow‐up high‐resolution TVS.