Colorectal cancer stands as one of the most prevalent cancers globally, representing 9.8% of total cases and contributing to 9.2% of mortalities annually. Robotic "front-wheel" navigating colonoscopes mitigate aggressive stretching against the long and tortuous colonic wall, alleviating associated discomfort and pain typically experienced by patients inspected by conventional "back-wheel" navigating colonoscopes. The anchoring unit of most "front-wheel" navigating colonoscopes plays a crucial role in ensuring effective locomotion by preventing slipping during elongation/contraction of the central actuation part. The soft balloon anchoring actuator emerges as a promising solution due to its high compliance. This study introduces a dumbbell-shaped balloon anchoring actuator (DBAA) integrating an "inflation and suction" mechanism to address the inherent conflict between achieving sufficient anchoring force and minimizing expansion and potential trauma of the colonic wall, commonly encountered in current balloon anchoring actuators. Analytical modeling of DBAA and soft external lumen, encompassing geometric deformation and anchoring force, were proposed to characterize the actuator and provide guidelines for designing and controlling DBAA in further applications, enabling autonomous anchoring within different diameter lumens and achieving the expected anchoring force. A comprehensive set of validation experiments was conducted, and the outcomes revealed high consistency with analytical predictions, confirming the effectiveness of the proposed analytical modeling approach. Furthermore, the results demonstrated a significant enhancement in anchoring force with the proposed actuator and corresponding mechanism while concurrently maintaining low-lumen expansion. For instance, in a lumen sample with R in=15mm, Λ2=105%, the anchoring force reaches 14.5 N with 50 kPa negative pressure, which is 12.4 times of the force (1.17 N) observed without applying negative pressure.

中文翻译：

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哑铃形球囊锚定致动器的设计和分析建模，用于安全有效地在胃肠道内运动。


结直肠癌是全球最普遍的癌症之一，占总病例数的 9.8%，每年占死亡率的 9.2%。机器人“前轮”导航结肠镜减轻了对长而曲折的结肠壁的剧烈拉伸，减轻了传统“后轮”导航结肠镜检查患者通常经历的相关不适和疼痛。大多数“前轮”导航结肠镜的锚定装置通过防止中央驱动部分伸长/收缩期间的滑动，在确保有效运动方面起着至关重要的作用。由于其高柔顺性，软球囊锚固致动器成为一种很有前途的解决方案。本研究介绍了一种哑铃形球囊锚定致动器 （DBAA），它集成了“充气和吸力”机制，以解决实现足够的锚定力与最大限度地减少结肠壁的扩张和潜在创伤之间的内在冲突，这在当前的球囊锚定致动器中很常见。提出了 DBAA 和软外腔的分析模型，包括几何变形和锚固力，以表征致动器，并为在进一步应用中设计和控制 DBAA 提供指导，实现不同直径管腔内的自主锚定并实现预期的锚固力。进行了一套全面的验证实验，结果显示与分析预测高度一致，证实了所提出的分析建模方法的有效性。此外，结果表明，在保持低管腔膨胀的同时，所提出的致动器和相应机构的锚定力显着增强。 例如，在 R in=15mm、Λ2=105% 的管腔样品中，在 50 kPa 负压下，锚固力达到 14.5 N，这是未施加负压时观察到的力 （1.17 N） 的 12.4 倍。