Reciprocally Rotating Magnetic Actuation and Automatic Trajectory Following for Wireless Capsule Endoscopy

Active wireless capsule endoscopy (WCE) under magnetic actuation is a promising technology to reduce the inspection time and relieve the burden of physicians. In this paper, we propose a reciprocally rotating magnetic actuation method for trajectory following of a capsule and develop its dynamic model. For the trajectory following task, we investigate the closed-loop tracking control strategies based on different controllers to actuate the capsule in the complex environments. The effectiveness of our method is validated in extensive experiments in a simulation environment as well as in an ex-vivo pig colon. The results demonstrate that the proposed method can accurately and efficiently actuate the capsule to follow the desired trajectory in the complex environments, achieving tracking errors on the order of millimeter. Moreover, the experiments on the ex-vivo pig colon show that the proposed reciprocally rotating magnetic actuation method has the potential to reduce the clinical risks and improve the safety and clinical acceptability of this technology.