An FBG-Based Clamping Force Sensor for Intervertebral Foraminoscopic Surgery

In this paper, a clamping force sensor for the nucleus pulposus forcep in intervertebral foraminoscopic surgery is proposed based on fiber Bragg grating (FBG). The sensor consists of a force-sensitive elastic beam and an optical fiber engraved with FBG. The force-sensitive elastic beam is designed to be located at the end of the forcep head to achieve clamp force sensing while ensuring the normal use of the nucleus pulposus forcep. This configuration provides a low transmission loss of clamping force and has the advantages of simple structure, easy installation and batch production. An optical fiber with fixed ends and suspended middle is arranged to increase the sensitivity while avoiding the chirp effect. The proposed sensor is derived and validated by finite element simulations. The Experimental results show that the sensor prototype has a measurement range of 0–5 N and a sensitivity of 59 pm/N, which indicates that the sensor can provide an ideal intraoperative feedback of clamping force on the nucleus pulposus forcep, facilitating the surgeon’s operation and improving the success of the surgery.