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

doi:10.1007/s12204-024-2717-0

Abstract

Abstract: 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.

Key words: near-infrared capsule robot, fluorescence imaging, wireless power transmission, three-dimensional receiving coil, design and optimization

摘要： 针对近红外胶囊机器人的能量供给不足、波动过大等问题，提出了一种无线能量接收线圈设计优化方法。首先通过电磁与电路分析，建立了无线能量传输系统的磁感应强度模型与等效电路模型。结合上述模型，以各维度绕组层数为优化变量，以接收端负载功率归一化标准差和空间尺寸为约束条件，以接收端负载功率平均值最大化为优化目标，建立了接收线圈的优化模型。最后，绕制了三种不同参数的三维接收线圈，通过实验测试了不同驱动电流下的接收端负载功率，对优化结果进行了验证。实验结果显示：接收端负载功率实验值与理论值变化趋势一致，实验值均小于理论值；接收端负载功率归一化标准差理论值为4.6%，平均实验值为9.6%。该研究解决了近红外胶囊机器人的供电问题，对胃肠道疾病的早期诊断和治疗具有重要意义。

关键词: 近红外胶囊机器人，荧光成像，无线能量传输，三维接收线圈，设计与优化

CLC Number:

Wang Wei, Zhou Cheng, Jiang Jinlei, Cui Xinyuan, Yan Guozheng, Cui Daxiang. Optimization of Wireless Power Receiving Coil for Near-Infrared Capsule Robot[J]. J Shanghai Jiaotong Univ Sci, 2025, 30(3): 425-432.

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