Rongguo Yan

Correction method for wireless electromagnetic localization of microcapsule devices.

In the development of a telemetry localization system for wireless tracking of a microcapsule medical device based on alternating current magnetic fields, further improvements are required in terms of localization accuracy and reductions in systematic error.

Hardy's Multi-Quadric method of calibrating a wireless electromagnetic localization system for intestinal micro-devices

A wireless electromagnetic localization method for tracking a medical micro-device in the gastrointestinal tract has been proposed and a prototype for the localization system has been developed. In the electromagnetic localization system, several excitation coils were mounted above the abdomen of human body to generate a varying electromagnetic field one by one. Then a wireless magnetic sensor was used to measure the magnetic field strength at the location of the micro-device. Thus the position and orientation of the micro-device could be obtained by solving the inverse problem of magnetic fields. In order to improve the localization precision, a global error correction technique based on the Hardys Multi-Quadric scattered data interpolation method was investigated to correct the static errors. In the calibration experiment, dependencies between true locations of the micro-device and the corresponding tracked locations within the operational space were established. Based on these data sets, the Hardys Multi-Quadric correction function was derived. The experimental results show that the localization error can be greatly reduced by using the Hardys Multi-Quadric correction method. The advantage of the approach is that it allows for smooth continuous mapping from the tracked space to the true space within the entire tracked space.