Optical Force and Torque Sensor for Flexible Robotic Manipulators

Robot-assisted Minimally Invasive Surgery (RMIS) typically uses a master–slave surgical configuration allowing surgeons to carry out surgical tasks remotely. In typical RMIS scenarios, the surgeons use visual information provided by a three-dimensional (3D) camera to interact with patients’ internal body organs via haptic interface devices. However, visual occlusion is one of the major drawbacks of the surgical approaches relying on visual information indicating the need for physical or virtual presence of the sense of touch during the operation. A multiaxis force sensor was developed to be integrated into the structure of surgical robots to enable continuous monitoring of external forces applied to the robot’s body, thereby assisting the surgeon in undertaking precise control actions using more accurate sensory information. In this chapter, we report on the STIFF-FLOP approach in design and implementation of a three-axis force sensor based on fiber optics. The sensing system has a hollow geometry, is immune to electrical noises and low cost, and hence, is suitable for integration into a wide range of medical and industrial manipulation devices