Toward a Fiber Bragg Grating-Based Two-Dimensional Force Sensor for Robot-Assisted Cardiac Interventions

Coronary heart disease (CHD) has one of the highest contribution to global health risks. In essence, CHD's economic burden cum the goal of achieving sustainable human health has attracted attention toward procedural innovations for better diagnosis and treatment of CHD. Despite having robotic systems paving the way towards reducing the perioperative risks faced by interventionists and patients, modeling and sensing of distal force feedback remain as an unsolved challenge. Of all sensing techniques adopted to solve this challenge, a fiber Bragg grating-based technique seems to be the most promising. In this letter, a prototype of a 3-D-printed 2-D distal force sensor is proposed for acquiring tool-vessel contact forces during robot-assisted cardiac procedures. The prototype consists of a symmetrical sensing structure designed with four optical fibers. Simulation and experimental studies were carried out to validate the applicability of the sensor. The simulation result shows that the force sensor could experience a minimal deformation under lateral forces of up to 1.0 N, whereas the in-lab temperature characterization study indicates that the sensor prototype has good linearity with increasing temperature between 35 and 54 °C. Thus, the fiber Bragg grating-based technique could enhance robot-assisted treatments of CHD.