Circular fold is one of the biggest barriers for resisting endoscopic robots moving in the small intestine. Overcoming such a resistance force for progression during endoscopic procedure may significantly improve diagnostic efficiency. This paper studies the locomotion of a vibro-impact capsule robot self-propelled on a small intestine substrate when encounters various types of circular folds. A new capsule-fold model is developed to understand capsule-fold interaction and determine the optimum control parameters (the frequency and amplitude of excitation) for a successful crossing motion. Extensive bifurcation analyses show that the geometry and mechanical properties of the circular folds do not have a significant influence on capsule’s bifurcation patterns but affect its progression in terms of fold crossing. To this end, numerical studies using path-following techniques implemented via the software COCO are performed. In this way, parameter-dependent families of periodic solutions of the capsule-fold model are studied, and critical points are detected to allow to develop control strategies for the capsule motion, in particular in order to cross certain types of circular folds by suitably varying its control parameters.

圆形褶皱是抵抗内窥镜机器人在小肠中移动的最大障碍之一。在内窥镜检查过程中克服这种进展阻力可以显着提高诊断效率。本文研究了一种在小肠基质上自行推进的振动冲击胶囊机器人在遇到各种类型的圆形褶皱时的运动。开发了一种新的胶囊折叠模型以了解胶囊折叠相互作用并确定成功交叉运动的最佳控制参数（激励的频率和幅度）。广泛的分叉分析表明，圆形褶皱的几何形状和机械性能对胶囊的分叉模式没有显着影响，但会影响其在褶皱交叉方面的进展。为此，使用通过软件 COCO 实现的路径跟踪技术进行数值研究。通过这种方式，研究了胶囊折叠模型的周期解的参数依赖族，并检测了临界点以允许开发胶囊运动的控制策略，特别是为了通过适当改变来跨越某些类型的圆形折叠其控制参数。