Numerical simulation of double impact 2DOF triboelectric energy harvesting for extended bandwidth

Increasing the bandwidth of the vibration energy harvesters is one of the research emphases to maximize the energy harvested from the ambient. Here we design a Two-Degree of Freedom Vibro-impact Triboelectric energy harvester with a double-impact configuration, which combines multi-modality and piecewise linearity to improve the harvesting bandwidth of triboelectric energy harvesters. The harvester structure consists of primary and secondary cantilever beams with two integrated energy harvesters. The two beams are designed to operate at close natural frequencies, and under the effect of the impact, triboelectricity is generated, and the bandwidths of the resonators are combined to create a wide bandwidth. The double impact system is investigated numerically to examine the structure’s dynamic behavior at different excitation levels, separation distance, and surface charge density to extract an optimal parameter for achieving a wide combined bandwidth. The system demonstrates the capability of connecting multi-modality and piecewise linearity to significantly broaden the triboelectric energy harvester’s bandwidth.