Combining orbit jump and potential wells optimizations for nonlinear vibration energy harvesters

Nonlinear vibration energy harvesters (VEHs) are widely used for scavenging vibrational energy due to their broadband behaviors. However, they exhibit multiple orbits of different powers for a given excitation, including low-power orbits that might limit their performance. To address this issue and enhance nonlinear VEHs performance, various studies have defined orbit jump strategies to transition from low-power to high-power orbits. Another way to maximize the power of nonlinear VEHs is to optimize their geometry by finely engineering their potential wells (PWs). In this letter, we propose an orbit jump strategy for bistable VEHs that combines the two latter approaches, i.e. that simultaneously optimizes their PWs while jumping from low-power to high-power orbits. This orbit jump strategy is optimized using a numerical criterion that takes into account the robustness of the jumps and the invested energy. The proposed orbit jump strategy has been experimentally validated for vibration frequencies between 30 and 60 Hz. It is shown that the proposed approach can increase the power by an average of 121 times over the considered frequency range. Compared to traditional orbit jump strategies, the proposed approach, which combines orbit jumping and PWs optimizations, increases by up to three times the harvested power.