Transcutaneous Energy-Transmitting Coils for FES.

Inductively coupled coils are thought to transfer electrical energy for functional electrical stimulation (FES). This paper describes methods for the design of spiral transmitting coils with amorphous magnetic fibers for FES loads. Generally. transmitting coils - for lighter loads need more winding turns. After determination of the size of coil, which corresponds to the power to be transmitted, the number of coil turns can be increased by using thinner conducting wires or by winding the wires in multi-lavers. In an investigation of the merits and demerits of each method, we were able to transmit electrical energy non-contactingly to loads of between 100 Ω and 250 Ω with a high efficiency of nearly 90%.