Velocity dependence of the characteristics of harmonic drive built-in torque sensing

We have proposed practical torque sensing which utilizes a flexible part of a harmonic drive gear. The sensing technique provides joint torque sensing without reducing stiffness of the robot and changing the mechanical structure of the joints. The characteristics of the torque sensing have been studied under an immovable condition. The dependence of characteristics on the rotational velocity have not been discussed. We describe the characteristics under rotational conditions of the harmonic drive. The experimental results show that the accuracy of the torque sensing under high velocity rotation is 2% of the gear torque capacity.