Optimization of Wireless Power Receiving Coil for Near-Infrared Capsule Robot

An optimizing method for designing the wireless power receiving coil (RC) is proposed in this paper to address issues such as insufficient and fluctuating power supply in the near-infrared capsule robot. An electromagnetic and circuit analysis is conducted to establish the magnetic induction intensity and equivalent circuit models for the wireless power transmission system. Combining these models involves using the number of layers in each dimension as the optimization variable. Constraints are imposed based on the normalized standard deviation of the receiving-end load power and spatial dimensions. At the same time, the optimization objective aims to maximize the average power of the receiving-end load. This process leads to formulating an optimization model for the RC. Finally, three-dimensional RCs with three different sets of parameters are wound, and the receiving-end load power of these coils is experimentally tested under various drive currents. The experimental values of the receiving-end load power exhibit a consistent trend with theoretical values, with experimental values consistently lower than theoretical values. The optimized coil parameters are determined by conducting comparative experiments, with a theoretical value of 4.6% for the normalized standard deviation of the receiving-end load power and an average experimental value of 9.6%. The study addressed the power supply issue of near-infrared capsule robots, which is important for early diagnosing and treating gastrointestinal diseases.