A Real-time Localization System for an Endoscopic Capsule

This paper presents a real-time magnetic tracking system for an endoscopic capsule intended to deliver biomarkers around specific locations of the gastrointestinal (GI) tract. Unlike radio frequency (RF) and ultrasonic signals, static magnetic signals suffer negligible attenuation within the human body. The magnetic tracking systems proposed to date use a large number of sensors, making them too complex to apply in practice. In this paper, a new magnetic tracking system is proposed with much reduced complexity. In this system, the capsule only needs a magnet for localization, and does not require any electronics or battery. Mathematical model and a tracking algorithm were developed to find the location of a magnetic marker in the gut. Laboratory test results and in vivo animal trials show that the system is capable of tracking a magnetic marker with expected accuracy.