Towards Automatic Stomach Screening Using a Wireless Magnetically Actuated Capsule Endoscope

Stomach cancer remains one of the primary health challenges with a high incidence and motility. Magnetically actuated capsule endoscope (MACE) provides a noninvasive and practical solution for stomach screening, due to its contactless actuation and high maneuverability. In this work, with an aim of shortening procedure duration and lowering surgeon workload, we propose an automatic stomach screening strategy by using a MACE to automatically detect and capture specific gastric features for mapping the whole stomach. To achieve this, an electromagnetic actuation system and a wireless MACE with real-time video transmission and orientation feedback are developed. Magnetic actuation modeling and kinematics analysis of the MACE are conducted, based on which an optimization-based position controller and a visual-servo-based orientation controller are designed. Simulative and experimental validation are conducted for proof-of-concept, with attractive results showing that the MACE can be accurately and stably controlled with a mean absolute position error of around 2.56 mm and an average convergent time of about 1.1 s for visual servoing and that automatic stomach screening is successfully demonstrated in a stomach phantom. The proposed stomach screening strategy using a MACE indicates high potential in clinical practice.