Towards External Sensor based Simultaneous Magnetic Actuation and Localization for WCE

This paper presents a close-loop simultaneous acceleration and localization system for the wireless capsule endoscopy inside the intestine for clinical applications. A compact capsule with two embedded magnetic rings is actuated by an external rotating magnet, and the magnetic fields of the three magnets are measured by an external sensor array. In the proposed workflow, the magnetic field of the external magnet is first eliminated using an Integral Filter based strategy. Then the magnetic field of the moving capsule is modeled to generate an estimation of its pose. The fusion of the actuation and localization steps are implemented using an Unscented Kalman Filter. The proposed method is validated through experiments on phantoms and animal organs. The localization accuracy of the capsule reaches 5.5mm and 5.2° for position and orientation, respectively.