Research on Elimination of Mutual Inductance of Multi-Dimensional Transmitting Coils for Capsule Robots

Capsule robots have received widespread attention because of their small size and active movement function, which can be used as a substitute of traditional endoscopes and capsule endoscopes. The power to the capsule robots is the key factor. To supply enough energy to the capsule robots, the stable and highly efficient wireless power transfer (WPT) system is needed. In this article, a multi-dimensional transmitting coils (MDTC) system is designed. The proposed transmitting coils system consists of two coil pairs, a Helmholtz coil pair and a saddle-shaped coil pair. In order to improve the stability and efficiency of the wireless power transfer system, the elimination of the mutual inductance between the Helmholtz coil pair and the saddle-shaped coil pair is analyzed. Then the optimal model of the transmitting coils is built to be used in the wireless power transfer system. The results present a better performance on stability and efficiency when the proposed transmitting coils with the elimination of the mutual inductance are applied to capsule robots with a receiving coil.