Vibration suppression control for a dies-driving spindle of a form rolling machine: Effects of a model-based control with a rotational speed sensor I

This paper deals with a control technique of eliminating the transient vibration generated in a dies-driving spindle of a form rolling machine. This technique is based on a model-based control with a rotational speed sensor in order to establish the damping effect at the driven machine part. A rotational speed sensor is installed in a driven gear, namely a bull gear. A control model is composed of a reduced-order mechanical part expressed as a transfer function between the rotational speed of the dies and that of the bull gear. This control model estimates a dies speed after the rotational speed of the bull gear is acted on the transfer function. The difference between the estimated dies speed and the motor speed is calculated dynamically, and it is added to the velocity command to suppress the transient vibration generated at the dies. In this paper, the performance of this control method is examined by simulations and experiments. The settling time of the residual vibration generated at the dies can be shortened down to about 1/2 of the uncompensated vibration level.