Resonant Power shoes for humanoid robots

A robust wireless power transfer system, containing primary and secondary coils, for a humanoid robot is proposed in this paper. Multiple primary coils constitute a `Power mattress´ structure on the ground, and a few secondary coils constitute a `Power shoe´ of a humanoid robot. When the foot wearing the power shoe is on the power mattress, a strong magnetic linkage is built up between the shoe and mattress; so wireless power is transferred through resonated circuits. When the foot is away from the mattress, then no power transfer occurs. Experiments for a power shoe of 2×4 coils with 2 cm square and a power mattress of 6×7 coils with 2.5 cm square at 133 kHz show robust power delivery characteristics regardless of footage with the maximum output power of 23.3 W.