Using robotic capsules for assessing gut health has been an emerging field since the early 2000s with researchers attempting to perform diagnosis, monitoring, and therapeutic functions inside the gut. The knowledge of peristaltic forces inside the intestine are crucial for designing the actuation mechanism of robotic capsules, however, the impact of peristalsis on a capsule has not yet been quantified. In this work, an analytical model is presented to study the peristaltic movement of the small intestine. For the first time, finite element simulations were conducted in COMSOL multiphysics to generate intestinal peristaltic forces, and analyze their impact on a robotic capsule. A capsule prototype (30 × $\phi$ 12 mm) was developed to measure the peristaltic forces from living intestinal tissue, while an embedded system was used simultaneously to record the live data from the capsule-intestine interaction. In in vitro experiments, the intestine applied an average axial force of 226 mN and contraction cycles of 9 times/min, while the capsule prototype experienced maximum radial force of 180 mN. A specialized in vitro setup is developed to keep fresh ex vivo intestine samples alive for up to 6 h, while the capsule prototype measured the intestinal forces from the living tissue. This in vitro experimental setup provided an excellent model for the in vivo environment in terms of generating peristaltic movements, hence this force analysis will help in developing efficient prototypes for locomotion, anchoring, localization, biopsy, drug delivery, and sampling mechanisms for robotic capsules.

中文翻译：

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活体肠道对机器人胶囊蠕动力的测量

自 2000 年代初以来，使用机器人胶囊评估肠道健康一直是一个新兴领域，研究人员试图在肠道内执行诊断、监测和治疗功能。肠道内蠕动力的知识对于设计机器人胶囊的驱动机制至关重要，但是，蠕动对胶囊的影响尚未量化。在这项工作中，提出了一个分析模型来研究小肠的蠕动运动。首次在 COMSOL multiphysics 中进行有限元模拟以生成肠道蠕动力，并分析它们对机器人胶囊的影响。一个胶囊原型（30 ×$\phi$ 12 mm) 被开发用于测量活体肠道组织的蠕动力，同时使用嵌入式系统记录胶囊-肠道相互作用的实时数据。在在体外实验中，肠道施加的平均轴向力为 226 mN，收缩周期为 9 次/分钟，而胶囊原型承受的最大径向力为 180 mN。一个专门的开发体外装置以保持新鲜 离体肠道样本可存活长达 6 小时，而胶囊原型测量来自活组织的肠道力。这个体外实验装置提供了一个很好的模型 在产生蠕动运动方面的体内环境，因此这种力分析将有助于开发用于机器人胶囊的运动、锚定、定位、活检、药物输送和采样机制的有效原型。