A broadband electromagnetic type energy harvester for smart sensor devices in biomedical applications

This paper presents the design, fabrication and experimentation of a low power Electromagnetic Energy Harvester (EM-EH) having a broader bandwidth. The proposed prototype exploits the human body motion to generate power for the low profile smart biomedical devices. The working of the proposed EM-EH is illustrated in both laboratory and in the real-time environment. The prototype of EM-EH is fabricated through computer numerical control milling and turning machines. The device is tested in-laboratory at different acceleration levels, and it was inferred that the EM-EH when excited at 3 g induces a maximum voltage of 3800 mV at a resonant frequency of 20 Hz. The results showed that the device successfully charged a completely discharged 1.5 V(2850mAH) battery within an hour. Additionally, the laboratory experimentation showed that EM-EH is more efficient for a widened operating bandwidth of 70Hz as compared to the conventional devices reported in the literature. Next, the real-time performance of the proposed EM-EH was investigated for harvesting energy from the human body motion such as walking, jogging, and stretching exercise with variable frequency vibrations.