Patent ID: 7205743

Claim:
A controller having a position control section and a velocity control section for respectively controlling position and velocity of a motor, to control relative motion of a driven element driven by the motor with respect to a machine effecting end of a machine tool, said controller comprising: position detecting means for detecting a position of the motor or the driven element; means for obtaining a first position deviation between a position command for the motor and the position of the motor detected by said position detecting means; acceleration detecting means for detecting an acceleration of the machine effecting end; conversion means for determining a position of the machine effecting end by converting the acceleration detected by said acceleration detecting means; means for obtaining a second position deviation by adding the obtained first position deviation and the determined position of the machine effecting end; and learning control means for calculating and outputting a correction value for converging the second position deviation to zero, wherein the correction value is added to the first position deviation and the sum obtained is multiplied by a position gain and the product obtained is outputted to the velocity control section as a velocity command.