A position telemetric method for implantable microcapsules in the gastrointestinal tract

摘要

In order to measure the position and orientation of implantable microcapsules in the gastrointestinal tract, a novel non-contact method based on electromagnetic induction was presented. Six cylindrical coils were arrayed on the abdominal surface of a human body. These coils were excited one-by-one in sequence with a sinusoidal signal to generate an alternating magnetic field. Meanwhile, a small induction coil along with a signal-processing circuit and radio-frequency transmitter was mounted inside the microcapsule to measure the magnetic signal produced by the six excitation coils. Based on the newly derived localization model and the particle swarm algorithm, the position and orientation of the microcapsule can be calculated. The experiments show that the localization system has good stability, high precision and wide localization range.