Passive-self-tunable vibrational energy harvester

In this paper, a passive self frequency tunable energy harvester, which can transduce vibration energy into electrical energy, is proposed. The proposed harvester is composed of cantilever couples which can be horizontally moved by the large deflection characteristics of a flexible cantilever. As the external vibration frequency fluctuate, the resonant frequency of the harvester can be tuned in real time by the change of the cantilever beam length through the movement of the cantilever couples. It was confirmed that the harvester can tune its resonant frequency ranged from 24Hz to 40Hz in real-time without an additional energy source.