抄録
Most Industrial robots are driven through reduction gears such as harmonic drives and RV gears. Since the exibility of the drive system, the vibratory behavior is caused duringthe operation. When the exibility is considered, the drive system of the robot joint can be modeled as a resonant mechanical system called two-inertia system. Two-inertia systems are the vibratory systems that have poles on/near the imaginary axis. Acceleration feedback and torque feedback are known as the vibration control methods of two-inertia systems. In this paper, we consider the two-inertia system with the feedbacks of motor-acceleration, load-acceleration and torsion-torque. It is shown that each feedback works to control the inertia-ratio of two-inertia system. Then, the control performances are compared. Torsion vibration in robot joint, which occurs owingto the accuracy of components and assembly error of gears at a certain speed of rotation, becomes a problem. In order to suppress the torsion vibration, each feedback is applied to the robot arm. As a result, the torsion vibrations are suppressed e ectively.