A systematic study of the low-frequency energy harvesting performance of a springassisted bistable dielectric elastomer generator (SBDEG) is presented in this paper. The SBDEG consists of a dielectric elastomer membrane (DEM) integrated with pre-compressed springs, enabling bistable dynamics under external excitations. Combined with the previously obtained dynamics model, the theoretical electrical model of the proposed system is developed to estimate the electrical output of the system and reveal its vibration energy harvesting (EH) mechanism. The theoretical model is validated through experiments with results showing good agreement between theoretical predictions and experimental outputs, and the vibration EH ability of the system in the typical low-frequency range lower than 5 Hz is confirmed. Numerical simulations are used to investigate the dynamical and electrical responses of the system under various excitation parameters, and the results show that the introduction of bistability can improve the low-frequency EH performance of the system. The influences of key system parameters, such as spring stiffness, DEM dimensions and excitation amplitude, on the EH performance of the SBDEG is also investigated. The findings show that adjusting these parameters can greatly enhance the system performance. Specifically, the proposed SBDEG achieves a high power density of 1.16×10 6 mW/m 3 under a low-frequency harmonic excitation of 5 Hz, which is significantly higher than that of representative existing dielectric elastomer generators (DEGs). These compelling quantitative results demonstrate the favorable lowfrequency EH performance of the SBDEG, making it a promising solution for practical applications.
Lai et al. (Thu,) studied this question.