Adaptive Wireless Biomedical Capsule Tracking Based on Magnetic Sensing

Abstract

This paper studies wireless biomedical capsule (WBC) tracking, for magnetic sensing and actuation settings, where an embedded permanent magnet is used inside a passive WBC together with magnetic sensors outside the human body, producing a magnetic field around the WBC. First, a 2D WBC localization scheme is developed based on only magnetic sensing and adaptive recursive least squares (RLS) on-line parameter estimation with forgetting factor. Next, we propose a hybrid localization technique for simultaneous position and orientation estimation with high accuracy. The proposed hybrid localization technique is based on data fusion of magnetic measurements and electromagnetic signals emitted by the WBC for image transmission and other medical information using a similar adaptive RLS parameter estimation scheme. Later, the proposed localization techniques are integrated with an adaptive tracking law to construct an adaptive capsule tracking controller. The simulations demonstrate promising results for the efficiency and accuracy level of the proposed adaptive localization and tracking control schemes.