Design and investigation of a torsional disc-triboelectric nanogenerator with magnetic tristable mechanism

Abstract

The torsional vibration widely exists in shafting and human joint motion, however, it is a significant challenge to harvest low-frequency torsional vibration energy over a broad frequency range by utilizing traditional triboelectric nanogenerator (TENG). Herein, a compact torsional disc-triboelectric nanogenerator (TD-TENG) with magnetic tristable mechanism is proposed, which has a low potential barrier and can efficiently convert low-frequency torsional vibration energy into electrical energy over a broad frequency range. The design inspiration of the TD-TENG is introduced firstly and then the working principle is presented. The theoretical model of the TD-TENG is established based on the Newton’s second law of motion and the theory of the TENG. The mechanical and electrical performances of the TD-TENG are obtained by using numerical simulations. The theoretical output voltages are validated by the electrical responses carried out using Simulink circuit model. Subsequently, the influences of the key parameters on the performance of the TD-TENG are studied. The prototype is fabricated and the experiment is conducted to validate the accuracy of the theoretical model of the TD-TENG. Furthermore, the output performance of the TD-TENG under human motion is tested, and the TD-TENG is used to power the LEDs and drive the temperature and humidity sensors under human motion. The results show that the TD-TENG can achieve a maximum output power of 0.64 mW, and its energy-harvesting bandwidth is four times wider than that of the bistable TENG. In addition, the TD-TENG exhibits superior output performance under human motion, capable of powering the LEDs and driving the temperature and humidity sensors, thus holding potential application prospects in the field of human health monitoring.