Abstract:
This paper presents vibration control of a flexible manipulator that has two links and three degrees of
freedom and that performs three-dimensional motion and verified the suppression of vibration in threedimensional space using an actual manipulator using an inverse system. At present, industrial robots are
required to increase the speed of operation in order to reduce the weight of the robot and improve the
work efficiency for the purpose of energy saving and cost reduction. However, if the weight of the arm
is reduced, the rigidity is inevitably low, which causes vibration of the entire arm. In addition, if the
operation speed is increased, vibration will occur in the arm even if the robot is highly rigid. For these
reasons, the development of a control method that takes into account the flexibility of the manipulator
is an important issue, and various studies have been conducted, but the study of vibration suppression
in three-dimensional motion is also difficult to model and control. One of the approaches is to suppress
vibration using an inverse system. Previous studies have shown that vibration suppression is possible
with the inverse system. Problems such as the resonance frequency component in the torsional direction
remaining and overshooting with respect to the target angle remain. Therefore, in this research, we
aimed to improve the vibration suppression performance in the torsional direction and the tracking
performance to the target angle, which remained as issues in the conventional research.
First, we applied and verified a new inverse system design method. We constructed a stable inverse
system using inner and outer decomposition for the unstable zero of the flexible manipulators and
confirmed the effectiveness for vibration suppression by simulation. After that, the vibration
suppression performance of the controller was confirmed in a mounting experiment, and it was
confirmed that it was effective in suppressing vibration in the torsion direction and the motor drive
direction. In addition, it was confirmed that overshoot with respect to the target angle, which was the
subject of conventional research, did not occur. From the results, it was confirmed that the proposed
inverse system is effective for vibration control of the flexible manipulator that moves in three
dimensions
