Wireless power transfer system for capsule robot designed by radial square transmitting coil pair with novel ferrite structure

Abstract

BACKGROUND: Wireless power transmission for capsule robots has always posed challenges due to the unpredictable postures. METHODS: A radial transmitting coil with a novel ferrite structure is proposed, which consists of two parts with the function of converging magnetic induction lines and reducing magnetic leakage. To improve the flux density, uniformity, and shielding effectiveness, the design parameters are discussed and optimized on the basis of analytical calculations and simulation analysis. RESULTS: The proposed ferrite structure improves the power transfer efficiency from 2.78% to 5.21%. Additionally, the power transfer stability showed a slight improvement from 76.4% to 77.6%, while magnetic leakage was reduced by 84%. Finally, the human tissue safety is also discussed and verified. CONCLUSIONS: The wireless power transfer system is shown to be feasible and safe.