Investigations of Vibration Energy Harvester Applying the Triangular Structure with a Tunable Resonant Frequency

PurposeThis paper investigates a vibration energy harvester with a triangular structure for lowfrequency vibrations, focusing on the analysis of nonlinear stiffness and damping characteristics generated by the structure itself for advantageous harvesting performance.MethodsFirst, Euler-Lagrange equation of the system is established based on Hamilton's principle. Then, with the mathematical modeling, the dynamic response of the system is derived using Harmonic Balance Method, which is discussed by numerical analysis. Based on the analytical solutions, the effects on harvesting power changed by different assembly angles, connecting rod length and excitation amplitudes are studied particularly. The advantageous harvesting performance of the proposed system is shown by comparing it with a corresponding conventional linear system.ResultsThe result shows that the triangular structure in the system is beneficial for expanding the power output and energy-harvesting bandwidth. Further, the resonant frequency of the system can be tuned to a desired value by adjusting the assembly angle according to the characteristics of surrounding vibration sources.ConclusionsTherefore, the harvester system in this work is demonstrated to provide an effective method for design to scavenge the low-frequency vibration energy from the ambient environment in engineering.