Proprioceptive magnetic-field sensing for closed-loop control of magnetic capsule endoscopes

The small intestine is the longest part of the gastrointestinal (GI) tract, but it is difficult to examine with traditional endoscopic procedures. To resolve this, swallowable capsules have been created that slowly pass through the entire GI tract taking images. Research is currently being done in magnetic actuation and localization to increase the speed and control of these smart pills. This paper focuses on a technique to more efficiently control a capsule endoscope based on proprioceptive sensing of the magnetic field. This sensing provides knowledge of the applied field in the frame of the capsule, and enables determination of its current state.