Vibration energy harvesting for low frequency using auto-tuning parametric rolling pendulum under exogenous multi-frequency excitations. Issue 6 (November 2020) - Punyakaew, Surat
HIGHLIGHTS: The authors present a novel auto-tuning vibration energy harvester in order to extract the energy from two-frequency vibration. A cam is designed to create multi (two)-frequency vibration. The proposed vibration energy harvester uses two rolling pendulum mechanisms. The resonance frequency of each rolling pendulum can be adjusted by geometrical tenability, adjusting the position of the sliding blocks, for matching the frequency of excitation The resonance frequencies of both rolling pendulum are successfully tuned when the angular velocity of the cam is in the range of 1.149 to 1.236 Hz ABSTRACT: An electromagnetic parametrically excited rolling pendulum energy harvester with self-tuning mechanisms subject to multi-frequency excitation is proposed and investigated in this paper. The system consists of two uncoupled rolling pendulum. The resonance frequency of each the rolling pendulum can be automatically tuned by adjusting its geometric parameters to access parametric resonance. This harvester can be used to harvest the energy at low frequency. A prototype is developed and evaluated. Its mathematical model is derived. A cam with rolling follower mechanism is employed to generate multi-frequency excitation. An experimental study is conducted to validate the proposed concept. The experimental results are confirmed by the numerical results. The harvester is successfully tuned when the angular velocity of the cam is changed from 1.149 to 1.236 Hz.