An infrasonic vibration energy harvester using pendulum impact

This paper presents experiments and finite element (FE) analyses of an infrasonic vibration energy harvesting device in which a low-frequency pendulum impacts a cantilever beam type energy harvester. The experiments demonstrate that the energy harvester operates in the frequency range of 2 similar to 8 Hz and has output power of several microwatts under 0.1 g excitation acceleration. Moreover, a finite element model with a coupling of impact, vibration, piezoelectricity and circuit is established and used to analyze the output voltage and power. The frequency response characteristics at different pendulum lengths and the distances between the pendulum ball and cantilever beams are measured and calculated, respectively. Useful guidelines for designing the energy harvester are obtained.