Currently used wireless capsule endoscopy (WCE) is limited in terms of inspection time and flexibility since the capsule is passively moved by peristalsis and cannot be accurately positioned. Different methods have been proposed to facilitate active locomotion of WCE based on simultaneous magnetic actuation and localization technologies. In this work, we investigate the trajectory following problem of a robotic capsule under rotating magnetic actuation in a tubular environment, in order to realize safe, efficient and accurate inspection of the intestine at given points using wireless capsule endoscopes. Specifically, four trajectory following strategies are developed based on the PD controller, adaptive controller, model predictive controller and robust multi-stage model predictive controller. Moreover, our method takes into account the uncertainty in the intestinal environment by modeling the intestinal peristalsis and friction during the controller design. We validate our methods in simulation as well as in real-world experiments in various tubular environments, including plastic phantoms with different shapes and an ex-vivo pig colon. The results show that our approach can effectively actuate a reciprocally rotating capsule to follow a desired trajectory in complex tubular environments, thereby having the potential to enable accurate and repeatable inspection of the intestine for high-quality diagnosis.
翻译:目前使用的无线胶囊内分镜(WCE)在检查时间和灵活性方面受到限制,因为胶囊是被动的,无法准确定位。提出了不同的方法,以同时磁振动和本地化技术为基础,促进主动移动静脉内分泌。在这项工作中,我们调查在管状环境中旋转磁振动的机器人胶囊问题之后的轨迹,以便利用无线胶囊内分镜对特定点的肠子进行安全、高效和准确的检查。具体地说,根据PD控制器、适应控制器、模型预测控制器和强大的多级模型预测控制器,制定了四个战略的轨迹。此外,我们的方法考虑到肠道环境中的不确定性,在控制器设计期间对肠道内渗透和摩擦进行模型建模。我们验证了在模拟中以及在各种管状环境中的实际世界实验中的方法,包括不同形状的塑料象素和前活性猪结肠。结果显示,我们的方法可以有效地使一个对等的旋转胶囊采取行动,以便通过对高质的气囊进行预期的心轴进行精确的反复检查,从而使精准的气压环境能够进行预期。