King's College London

Research portal

Development of a Fiber Bragg Grating-Enabled Clamping Force Sensor Integrated on a Grasper for Laparoscopic Surgery

Research output: Contribution to journalArticlepeer-review

Kai Sun, Ming Li, Shuxin Wang, Guokai Zhang, Hongbin Liu, Chaoyang Shi

Original languageEnglish
Article number9437177
Pages (from-to)16681-16690
Number of pages10
Issue number15
Accepted/In press2021
Published1 Aug 2021

Bibliographical note

Funding Information: Manuscript received April 19, 2021; revised May 13, 2021; accepted May 15, 2021. Date of publication May 20, 2021; date of current version July 30, 2021. This work was supported in part by the Natural Science Foundation of Tianjin City under Grant 18JCYBJC41400, in part by the National Natural Science Foundation of China under Grant 61973231, and in part by the U.K. Engineering and Physical Sciences Research Council (EPSRC) Low Cost Morphable Teleop-erated Endoscope for Gastric Intestinal Tract Screening (LoCoMoTE) Project under Grant EP/R013977/1. The associate editor coordinating the review of this article and approving it for publication was Dr. Ing. Emiliano Schena. (Kai Sun and Ming Li contributed equally to this work.) (Corresponding author: Chaoyang Shi.) This work involved human subjects or animals in its research. Approval of all ethical and experimental procedures and protocols was granted by the Animal Ethical and Welfare Committee (AEWC), China, with an animal experiment license under Approval No. SYXK2019 0018. Publisher Copyright: © 2001-2012 IEEE. Copyright: Copyright 2021 Elsevier B.V., All rights reserved.

King's Authors


This paper presents a clamping force sensor based on fiber Bragg grating (FBG) to provide interaction force feedback for laparoscopic surgery. The proposed sensor mainly consists of a force-sensitive clamping flexure and a tightly suspended optical fiber with an FBG inscribed. The force-sensitive clamping flexure utilizes a bridge-type structure with an excellent load-bearing capacity and anti-interference ability to linearly convert the vertical force or displacement input exerted on the grasping surface into translational deformation along the flexure central line. The FBG fiber is arranged along the flexure central axis to sense the vertical force-induced horizontal strain. This two-point pasting configuration can achieve a uniform fiber strain distribution and an enhanced sensitivity. This assembly arrangement produces a linear relationship between the applied vertical force and the force-induced horizontal strain value sensed by the FBG. The force sensitivity remains the constant and it less affected by the grasping positions due to the high stiffness and deformation conversion, overcoming the difficulty that the traditional clamping force sensor designs are sensitive to the grasping position due to the variable grasping positions and areas on the soft tissues during clamping. The finite element method (FEM)-based simulation has been utilized for design optimization and performance investigation to guide the sensor design. The simulation sensitivity values have been determined as a close value of 52pm/N regarding the three different grasping positions at middle, left and right parts. The optimized sensor design has been integrated into a manual surgical grasper and achieve experimental sensitivity values of 56.2pm/N, 51.1pm/N and 47.5pm/N for the three different loading positions within 0, 10N. Both dynamic loading experiments and clamping experiments on ex-vivo tissues and in-vivo animal for tissue resection were implemented to validate the effectiveness of the proposed design.

View graph of relations

© 2020 King's College London | Strand | London WC2R 2LS | England | United Kingdom | Tel +44 (0)20 7836 5454