Frequency up-converting Vibration Energy Harvester with Multiple Impacting Beams for Enhanced Wideband Operation at Low Frequencies

AbstractThis work presents an approach for increasing operational bandwidth of a vibration energy harvester in low-frequency environments by effectively exploiting contact-based frequency up-conversion. It was implemented by a couple of low-frequency resonators with appropriately spaced natural frequencies impacting high-frequency piezoelectric generators when the device is harmonically excited in 10-40Hz range. A proof of concept was designed, modeled, fabricated and characterized, demonstrating improved power and bandwidth performance (up to 37μW and 9Hz at 1g) with respect to traditional single-resonator designs