Harvesting energy from arbitrary horizontal vibration through a quad-stable magnetic rolling pendulum

Abstract A magnetic rolling pendulum quad-stable energy collector (MRP-QEC) is proposed to scavenge energy from arbitrary horizontal vibration in the environment. The MRP-QEC offers the advantage of low damping and is sensitive to in-plane vibration in any direction. By developing the dynamic model, numerical simulations reveal that the moving magnet in the MRP-QEC exhibits three patterns of oscillation when subjected to external excitations, namely the intra-well oscillation, inter-well chaotic oscillation, and full rotation motion, with the latter demonstrating the highest energy harvesting efficiency. Experiments under sweep frequency excitation indicate that the full rotational motion could be observed at a very low frequency when a proper perturbation is applied, and then lasts to the frequencies of 20.9 Hz, 22.1 Hz, and 23.4 Hz for excitation levels of 0.27 g, 0.3 g, and 0.33 g, with a peak voltage of 4.9 V produced. Under 9.4 Hz/0.33 g excitation, the matched load resistance witnesses a maximum average power of 2.53 mW, and the peak power reaches 7.28 mW. Furthermore, charging a 220 μ F capacitor under harmonic excitation for 10 s, the MRP-QEC could enable the hygrothermograph, timer, and watch to operate for 68 s, 237 s, and 293 s respectively, demonstrating the MRP-QEC’s broad application prospect.