Multimodal Fiber Somatosensory: Optical Fiber 'Nerves' Empower Continuum Surgical Robots With Multimodal Feedback.

To achieve the force sensing at the sub-5 mm end effector of a continuum robot, optical fiber 'nerves' -incorporating the Fabry-Pérot (FP) cavity and step-etched fiber Bragg gratings (FBGs) was proposed to sense the multimodal forces (clamping force, 3-axis wrist force, and driving force) and shape awareness. The proposed laser-welded package solved the problem of clinical application adaptability, enabling the robot to withstand sterilization (15 cycles) and maintain an error of <5% over 60 days of operation. Combined with the in situ calibration method, the surgical robot can maintain high force measurement accuracy in cadaver specimens and live animal experiments. The master-slave teleoperation system with feedback of clamping and 3-axis wrist force also reduces the operation force by 30%-40%, improving the safety of surgical operations. The proposed method opens new avenues for developing smart surgical instruments with inherent sensing capabilities.