Contact Force Control of a Robotic Hand Using F/T Sensory Feedback with a Rigid Object

Abstract

There have developed various robotic hands since the 1960’s with the control theories. For a robotic hand, manipulating objects as human does is a quite difficult story and grasping or pinching objects should be preceded before manipulation. Those operations are based on interaction between robotic hand and arbitrary objects. It means how strongly a robotic hand grasps arbitrary object with stable and unbreaking motion when interactions occur. This paper attempts a grasping force control of a velocity controlled robotic hand using external Force/Torque (F/T) sensors. This control uses F/T sensor feedback and produces a command torque. Then, velocity-torque transformer converts a command torque into an input velocity to the robotic hand system. The algorithm is analyzed through an experiment that shows how a grasping force affects arbitrary objects and obtained competent results.