肠道微型仿尺蠖式机器人机载供能线圈优化

Optimization of a Powering Coil Onboard a Dime-Size Inchworm-Like Robot for Exploring the Intestine

采用无线电能传输技术供能的微型仿尺蠖式机器人在肠道疾病微创诊疗方面具有重要的应用价值,其机载供能线圈由圆环形磁芯和缠绕于磁芯上的圆环形绕组构成.本文提出一种机载供能线圈快速设计优化方法.首先,通过对绕组中各匝绕线进行几何建模,测定磁芯磁导率分布,分析金属零件涡流效应对供能线圈参数影响,建立了供能线圈的集成环境模型.然后,结合电磁理论,计算了供能线圈在集成环境中的互感和等效串联电阻.最后,以最大化供能线圈输出功率为目标,在温升安全性要求和机器人内部空间约束下,对绕组的轴向位置、层数、匝数和线径进行优化,获得了各设计参数选取的一般性结论.采用优化设计参数的绕组尺寸仅为(12.0~12.4)mm×9.9 mm,当其位于磁芯轴向中心位置时,输出功率高达1478.3mW.

A dime-size inc hworm-like robot,which adopts wireless power transmission for power supply,has a great potential for a minimally invasive intestinal exploration.The powering coil onboard the robot is usually composed of a ring-shaped ferrite core and a ring-s haped winding.This paper presents a fast design method for power coil.Firstly,the integrated environment model of the powering coil is established by modeling the geometry of the ring-shaped winding,measuring the permeability distri bution of the ferrite core,and analyzing the influence of eddy-current effect of the metal parts on the powering coil.Then,by referring to electromagnetic theory,the equivalent series resistance and mutual inductance of the powering coil are calculated.Finally,axial location,number of layers,number of turns,and wire diameter of the winding are opt imized,with an aim of maximizing the output power of the powering coil and with a consideration of temperature rise safety and limited space.And some guiding rules for selecting the design parameters are obt ained.The optimized winding,having a compact size of 0(120-124)mmX99 mm,can output an electric power of 14783 mW.