Design, modeling and experiments of bistable wave energy harvester with directional self-adaptive characteristics

Wave energy is a abundant renewable resource, but the direction variability and ultra-low frequency limit its widespread application. Therefore, a novel bistable wave energy harvester with directional self-adaptive characteristics is proposed in this paper, which utilizes the collision between the driving ball and the generator beam to transform the multi-directional ultra-low frequency wave vibration into localized high-frequency vibration. Moreover, the theoretical analytical model of harvester when subjected to wave motions was established, including the dynamic analysis of driving ball before the collision, the collision response analysis during the collision, and the bistable properties of generator beam after the collision. Finally, the key parameters affecting the output performance, such as the mass of the driving ball, the maximum inclination angle of the wave and the external load resistance, were analyzed using experiments. The maximum open-circuit voltage RMS value is 1815.28 mV, and the maximum power is 2.06 μW. The proposed harvester can effectively harvest ultra-low frequency energy vibration energy in multi-directions. •A novel bistable wave energy harvester with directional self-adaptive characteristics (BWEH-DS) is proposed.•A theoretical analytical model of BWEH-DS is established and validated experimentally.•The maximum open-circuit voltage RMS value is 1815.28 mV, and the maximum power is 2.06 μW.