Vitreoretinal surgery requires exceptional precision, stability, and dexterity. The issues related to retinal surgery include, (a) potential sclera stress and intraocular lens collision induced by the use of conventional rigid straight tools, and (b) the small tool-to-tissue interaction force that is normally imperceptible to surgeons. Recently, concentric tube-based robots (CTRs) have been adopted to solve the aforementioned issues in vitreoretinal surgery. However, the tip force sensing capability in CTRs owing to their dimensional constraints for sensor embedding is one of the challenging issues that CTRs face. This work introduces a novel slot-based force sensing module to be used in a sub-millinewton force sensing concentric tube (CT)-based eye surgery robot. The module is composed of half-cut slots and fiber Bragg grating (FBG) sensors. The force sensing module was modeled analytically using the composite beam theory to analyze its characteristics. To verify the analytical model, finite element analysis (FEA) was carried out in a simulation environment, and experiments using a prototype were performed to obtain the force–strain relationship. The FEA and experimental results show that the composite beam model is highly compatible with the force sensing module and that the module can detect transverse forces with a resolution of 0.25 mN. It was also verified that the slot-based force sensing module can be integrated into the inner tube of a CT-based eye surgery robot with a diameter of 0.43 mm.

玻璃体视网膜手术需要出色的精度，稳定性和灵巧性。与视网膜手术有关的问题包括：（a）使用传统的刚性笔直工具可能引起的巩膜应力和眼内晶状体碰撞，以及（b）外科医生通常无法察觉的较小的工具与组织之间的相互作用力。近来，已经采用基于同心管的机器人（CTR）来解决玻璃体视网膜手术中的上述问题。然而，由于CTR的尺寸限制，其在传感器中的埋入力，其尖端力感测能力是CTR面临的挑战性问题之一。这项工作介绍了一种新颖的基于缝隙的力感测模块，该模块将用于基于亚军事力的同心管（CT）眼科手术机器人。该模块由半切槽和光纤布拉格光栅（FBG）传感器组成。使用复合梁理论对力感测模块进行了建模分析，以分析其特性。为了验证分析模型，在模拟环境中进行了有限元分析（FEA），并使用原型进行了实验以获得力-应变关系。有限元分析和实验结果表明，复合梁模型与力传感模块高度兼容，并且该模块可以检测到0.25 mN的横向力。还证实了基于槽的力感测模块可以集成到直径为0.43 mm的基于CT的眼科手术机器人的内管中。在模拟环境中进行了有限元分析（FEA），并使用原型进行了实验以获得力-应变关系。有限元分析和实验结果表明，复合梁模型与力传感模块高度兼容，并且该模块可以检测到0.25 mN的横向力。还证实了基于槽的力感测模块可以集成到直径为0.43 mm的基于CT的眼科手术机器人的内管中。在模拟环境中进行了有限元分析（FEA），并使用原型进行了实验以获得力-应变关系。有限元分析和实验结果表明，复合梁模型与力传感模块高度兼容，并且该模块可以检测到0.25 mN的横向力。还证实了基于槽的力感测模块可以集成到直径为0.43 mm的基于CT的眼科手术机器人的内管中。