Determination of object stiffness control parameters in robot manipulation using a prototype optical three-axis tactile sensor

This paper presents experimental results to define suitable parameters in object stiffness control using a prototype optical three-axis tactile sensor mounted on robotic fingers. We have developed a novel optical three-axis tactile sensor system based on an optical waveguide transduction method applying image processing technique. We conducted a series of calibration experiments with soft and hard objects to define suitable parameters in object stiffness control. We analyzed normal and shearing forces data detected in the experiments and compiled suitable parameters in an algorithm inside the robot control system. Verification experiment using robotic fingers to manipulate soft object was conducted whose result revealed that the fingerpsilas system managed to recognize the stiffness and safely manipulate the object.