胃肠道内目标物电磁跟踪定位系统设计及实验研究

Design and experimental study of an electromagnetic tracking and locating system for targets in GI tract

研究了可用于胃肠道内微型诊疗装置位置连续跟踪的电磁跟踪定位方法。利用泰勒级数展开方法，在筒化的单圆环线圈模型基础上建立了电磁跟踪定位系统数学模型，完成了便携式定位系统设计。通过仿真实验方法优化了系统部分结构参数，确定了体外励磁线圈个数及布置方式，并开展了系统实验研究。实验结果表明，在覆盖人体消化道区域的定位空间内，系统最大定位误差小于3cm，平均定位误差为1．56cm，此方法不仅可行，而且定位精度也能满足应用需求。

The electromagnetic tracking principle for continuously locating micro-devices working in and moving along the gastmintestinal tract was studied. Based on the simplified circular loop model, a mathematil model for electroinagnetic tracking and locating systems was derived using the Taylor＇ s series expansion method, and then a portable tracking system was designed, which included two major parts working in vivo and in vitro respectively. The simulation analysis was made to optimize part of the design parameter of the system, and to determine the optimal number and the layout of the exciting coils. The experimental study was also carried out and the results showed that in the locating range covering the GI tract, the maximum position error was less than 3cm, and the average error was 1.56cm. The performance of the system can meet the requirements of the in vivo targets tracking.