Microsurgery is a particularly impactful yet challenging form of surgery. Robot assisted microsurgery has the potential to improve surgical dexterity and enable precise operation on such small scales in ways not previously possible. Intraocular microsurgery is a particularly challenging domain in part due to the lack of dexterity that is achievable with rigid instruments inserted through the eye. In this work, we present a new design for a millimeter-scale, dexterous wrist intended for microsurgery applications. The wrist is created via a state-of-the-art two-photon-polymerization (2PP) microfabrication technique, enabling the wrist to be constructed of flexible material with complex internal geometries and critical features at the micron-scale. The wrist features a square cross section with side length of 1.25 mm and total length of 3.75 mm. The wrist has three tendons routed down its length which, when actuated by small-scale linear actuators, enable bending in any plane. We present an integrated gripper actuated by a fourth tendon routed down the center of the robot. We evaluate the wrist and gripper by characterizing its bend-angle. We achieve more than 90 degrees bending in both axes. We demonstrate out of plane bending as well as the robot's ability to grip while actuated. Our integrated gripper/tendon-driven continuum robot design and meso-scale assembly techniques have the potential to enable small-scale wrists with more dexterity than has been previously demonstrated. Such a wrist could improve surgeon capabilities during teleoperation with the potential to improve patient outcomes in a variety of surgical applications, including intraocular surgery.

翻译：显微外科是极具挑战性但又影响深远的手术方式。机器人辅助显微外科有望提升手术灵活性，实现此前无法达到的微小尺度精密操作。眼内显微外科尤其困难，主要原因在于经眼插入的刚性器械难以获得足够自由度。本文提出一种面向显微外科应用的新型毫米级灵巧腕部设计。该腕部采用先进的双光子聚合（2PP）微加工技术制造，使腕部能够由柔性材料构成，并具备复杂内部几何结构和微米级关键特征。腕部横截面呈边长1.25mm的正方形，总长3.75mm。其结构中穿有三根腱绳，通过小型线性执行器驱动可实现任意平面内的弯曲。我们进一步设计了由第四根穿过机器人中心的腱绳驱动的集成夹爪。通过表征弯曲角度对腕部及夹爪性能进行评估，实现了两轴超过90度的弯曲。实验验证了面外弯曲能力及机器人在驱动状态下的抓取性能。所提出的集成夹爪/腱驱动连续体机器人设计及介观尺度装配技术，有望实现比此前展示方案更具灵活性的微小尺度腕部结构。此类腕部在遥操作手术中可提升外科医生操作能力，有望改善包括眼内手术在内的多种外科手术的患者预后。