To prevent vibration of a machine table used as a movable member for a variety of machines generated at the time of acceleration or deceleration.

This device is provided with a computation circuit 22 to determine an acceleration speed signal to be outputted based on a machine table acceleration/deceleration instruction signal, and an active damper drive circuit 23 to output a control signal corresponding to the acceleration signal inputted from the computation circuit to an active damper. By active damper braking force based on the control signal from the active damper drive circuit 23, vibration of the machine table at the time of acceleration or deceleration is controlled to prevent vibration.