Control method and control device

A control method that performs position control of a control object while compensating for backlash in the control object, the control object being configured to move periodically along a movement path, the control method comprising:

• a final position command signal generating step of generating a final position command signal by shifting a backlash quantity signal that compensates for the backlash and adding the backlash quantity signal to a position command signal indicating a position of the control object;
• and
• a position control step of performing position control of the control object on the basis of the final position command signal generated in the final position command signal generating step;
• wherein the final position command signal generating step includes:
• a position command signal generating step of generating the position command signal;
• a control direction detecting step of detecting, on the basis of the position command signal generated in the position command signal generating step, a control direction for controlling the control object;
• a backlash quantity calculating step of generating, in accordance with the control direction detected in the control direction detecting step, a backlash quantity signal for compensating for the amount of backlash in the control object, the backlash quantity signal being a stepped control direction signal having a positive or a negative value of 1 multiplied by a backlash compensation gain;
• a delay time calculating step of generating a backlash correction signal by delaying, by a predetermined delay time with respect to the position command signal, the backlash quantity signal generated in the backlash quantity calculating step where the predetermined delay time is set longer than or equal to the length of time from when the control direction detected in the control direction detection step is reversed to when a behavior of the control object is actually reversed;
• and
• a signal adding step of generating a final position command signal by adding the backlash correction signal generated in the delay time calculating step to the position command signal, and
• wherein the position control step controls the position of the control object on the basis of the final position command signal generated in the signal adding step.