Design and experimental investigation of a high-efficiency rolling electromagnetic energy harvester with an arc-shaped track

Abstract

Rolling electromagnetic energy harvesters (REMEH) is efficient vibration energy harvesting devices. A REMEH with an arc-shaped track (REMEH-AT) is proposed in this paper to better tune with the human motion frequencies and enhance its energy harvesting performance from human motion. A high-density array coil further increases the change rate of the magnetic flux. A rolling-collision mathematical model of the REMEH-AT is established based on the extended Hamiltonian principle. The output voltage and power characteristics with different arc-shaped track radii are studied by using numerical simulation, vibration shaker tests, walking and running tests, and hand shaking tests. The numerical and vibration shaker test results are in good agreement, verifying the accuracy of the mathematical model and numerical simulations. The experimental results demonstrate that the output performance of the REMEH-AT exhibits significant excitation amplitude-dependent nonlinearity. The arc-shaped track can significantly improve the harvesting performance of the REMEH-AT. The R30 and R50 typed harvesters are beneficial for harvesting energy from walking/jogging (low frequencies) and running (high frequencies), respectively. An excessively large track radius will reduce the harvesting performance. The proposed REMEH-AT provides an efficient and robust solution for potential clean power supply in intelligent wearable electronic and wireless sensor network devices.