应用磁传感器阵列定位跟踪消化道诊疗胶囊  

Localizing and tracking of medical capsule in human by magnetic sensor array

作　　者：郑小林[1] 李金[1] 侯文生[1] 何金[1] 

机构地区：[1]重庆大学生物工程学院,重庆400030

出　　处：《光学精密工程》2009年第3期576-582,共7页Optics and Precision Engineering

基　　金：国家自然科学基金资助项目(No.30700160);重庆市自然科学基金资助项目(No.CSTC2006BA5005)

摘　　要：为实现对消化道微型诊疗装置在人体内的实时定位与跟踪,建立了一种基于三轴磁传感器阵列的磁目标实时定位跟踪系统。该系统使用磁偶极子模型作为永磁体的磁场分布模型,用4×4的三轴磁传感器阵列检测固定在电子胶囊中的永磁体产生的磁场,通过控制电路和USB接口适配器,将检测出的磁场信号传入计算机,使用非线性最优化方法由磁场信号解出电子胶囊的位置和姿态信息,最后由定位软件实时显示定位结果并保存数据。实验结果表明,该系统对于距离传感器阵列平面150mm的电子胶囊,平均定位精度<7mm,平均定向精度<6°;同时,该系统能够对距离传感器阵列平面60～220mm的模拟肠道内运动的电子胶囊实现实时跟踪;并且该系统对人体、织物、塑料等非磁性介质不敏感,基本上能够满足消化道微型诊疗装置在人体内的实时定位与连续跟踪的要求。A localizing and tracking system based on magnetic sensor array is proposed to realize the real time localizing and tracking of the micro diagnosis and treatment devices in human Gastrointestinal tract （GI tract）. This localizing system uses magnetic dipole model as mathematic model for magnetic field of permanent magnet and uses a 4 × 4 three axis magnetic sensor array to measure the magnetic field. A control circuit and an USB adaptor are used to transport the signal to the computer, then, the position and posture parameters of the magnetic object are computed by a nonlinear optimization method. Finally,a program is developed to display and save the localization result in real time. The real experimental results show that the average localization error is less than 7 ram, the average orientation error is less than 6°when the capsule is 150 mm away the sensor array plane. At the same time, this localizing system is able to track the capsule that moves among a simulated intestinal tract. Moreover, the localization error is not sensitive to glass, plastic, clothes, water and human body. It is conclusion that this localizing system is able to realize the real time localizing and tracking of the micro diagnosis and treatment devices in human GI tract.

关 键 词：定位 实时跟踪 磁传感器 磁场检测 微型诊疗装置 

分 类 号：TP212.13[自动化与计算机技术—检测技术与自动化装置] TM936[自动化与计算机技术—控制科学与工程]