Design and Analysis of a Shoe-Embeded Power Harvester Based on Magnetic Gear

This paper presents a shoe-sole-embedded power harvester which can extract power from walking to charge portable or mobile electronic devices. The core component of the design is a combination of a trans-rotary magnetic gear (TRMG) and a disk-type axial-flux permanent magnet (AFPM) generator. The key idea is to convert linear foot motion into rotation using the TRMG, so that the AFPM can be driven to generate electric power. The proposed energy harvester has a high power density due to its electromagnetic nature. Moreover, by integrating a TRMG, it eliminates the mechanical problems caused by the conventional transmission mechanisms, which also makes it compact in size. Besides introducing its structure and working principle, the design procedure is presented and its performance is analyzed using the finite-element method.