CONIX Publication

Complex gesture recognition and multi-degree-of- freedom prostheses necessitate the ability to chronically record electromyography (EMG) signals from multiple physically distant muscles. This paper presents an inductive wireless power transfer (WPT) system for a distributed EMG recording platform that can power multiple implants via a homogeneous magnetic field. The proposed coil array is designed to optimally power randomly dis- tributed implants across a large area on the forearm. Efficiency is maximized by carefully optimizing the geometry of the hexagonal sub-coil of the array and the frequency of the WPT, while field homogeneity is maximized by stacking three horizontally offset layers of coils in order to minimize magnetic field variations. The array achieves best-case, worst-case, and average efficiencies of 70.3%, 65.5%, and 68.5%, respectively, enabling efficient power delivery to multiple randomly distributed implants.