Wireless charging of unmanned aerial system (UAS) platforms from the environment has the potential to greatly increase flight and mission times. A promising option is to use electromagnetic fields from the power transmission infrastructure as an energy source. EH Group and the University of Alabama propose a design for UAS wireless charging in the near-field environment of the commercial power transmission infrastructure. Conventional coil designs have maximum coupling efficiency only when the plane of the coil is perpendicular to the magnetic field. The key innovation proposed is a novel power-receiving coil that has high coupling efficiency regardless of orientation angle of the UAS with the magnetic field. The technical objectives are to (1) develop a working model of the power-receiving coil and circuit board, (2) conduct analyses to determine coil-based charging performance and battery size requirements under a variety of conditions, and (3) validate the design and analysis through bench testing. The feasibility of the Phase I work will be demonstrated when the proposed novel power-receiving coil achieves charging performance goals within a small or micro UAS considering trade-offs between energy transfer efficiency, resistive loss, size, and weight under multiple environmental conditions and orientations.
