Design and characterization of a low frequency 2-dimensional magnetic levitation kinetic energy harvester

This paper presents the design and characterization of the first completely orientation-independent magnetic levitation energy harvester for low power, low frequency, and low g applications. A fully symmetric design is presented able to operate in any orientation in a particular plane. A MATLAB/Simulink model has been developed to aid in optimizing harvester design. Resonant frequencies in the order of 2 Hz are desirable for human walking motion energy harvesting applications. The presented harvester has been tuned to a resonant frequency of 8.2 Hz, allowing it to take advantage of harmonics available from human walking motion. The harvester may be tuned to different frequencies with different magnet configurations and harvester dimensions with the aid of the MATLAB/Simulink model. The presented energy harvester has a measured power output of 41.0 μW and 101 μW at 0.1 g and 0.2 g accelerations, respectively.