The overtube of an endoscopic surgery robot is fixed when performing tasks, unlike those of commercial endoscopes, and this overtube should have high structural stiffness after reaching the target lesion so that sufficient tension can be applied to the lesion tissue with the surgical tool and there are fewer changes in the field of view of the endoscopic camera from this reaction force. Various methods have been proposed to reinforce the structural stiffnesses of hyper-redundant manipulators. However, the safety, rapid response, space efficiency, and cost-effectiveness of these methods should be considered for use in actual clinical environments, such as the gastrointestinal tract. This study proposed a method to minimize the positional changes of the overtube end tip due to external forces using only auxiliary tendons in the optimized path without additional mechanical structures. Overall, the proposed method involved moving the overtube to the target lesion through the main driving tendon and applying tension to the auxiliary tendons to reinforce the structural stiffness. The complete system was analyzed in terms of energy, and the sigmoidal auxiliary tendons were verified to effectively reinforce the structural stiffness of the overtube consisting of rolling joints. In addition, the design guidelines of the overtube for actual endoscopic surgery were proposed considering hollowness, retroflexion, and high structural stiffness. The positional changes due to external forces were confirmed to be reduced by 60% over the entire workspace.

中文翻译：

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S 形辅助肌腱驱动机构增强内窥镜手术超冗余机械手的结构刚度

与商用内窥镜不同，内窥镜手术机器人的外套管在执行任务时是固定的，外套管到达目标病灶后应具有较高的结构刚度，以便手术工具能够对病灶组织施加足够的张力，并且具有该反作用力对内窥镜摄像机视野的影响较小。已经提出了各种方法来加强超冗余机械手的结构刚度。然而，在胃肠道等实际临床环境中使用时，应考虑这些方法的安全性、快速响应、空间效率和成本效益。本研究提出了一种方法，仅使用优化路径中的辅助筋，无需额外的机械结构，即可最大限度地减少外力引起的外套管端头位置变化。总的来说，所提出的方法包括通过主驱动肌腱将外套管移动到目标病变处，并对辅助肌腱施加张力以增强结构刚度。对整个系统进行了能量分析，并验证了S形辅助筋有效地增强了由滚动接头组成的外套管的结构刚度。此外，考虑到中空、后屈和高结构刚度，提出了用于实际内窥镜手术的套管设计指南。