High Dynamic Range Force Sensing of a Robot Hand Combining Signals on Tip and Wrist

Abstract

When a robot grasps a tool, the force at the tip of the tool needs to be determined. However, the vibration noise caused by the inertial force of the hand is a major factor that degrades the force-sensing performance. In this study, we develop a gripper force sensor that uses the structure of the fingertip as a flexure element and integrates the response with that of a wrist force sensor to ensure high force-sensing performance. It can measure small external forces and has high load capacity. The measurement range of the gripper force sensor is 0.005 N to 10 N, and the overload capacity exceeds 50 N. We experimentally demonstrate that hand vibration does not degrade the force detection performance, and that the dynamic range of the force can be extended. In addition, we show through a drawing demonstration that a fine adjustment of the force can be achieved.