Method for suppressing variation in speed of actuator

A method for suppressing variation in rotational speed of an output shaft of an actuator provided with a motor and a wave gear drive, the method for suppressing variation in speed of an actuator in comprising:

• using an absolute position of one revolution of a motor rotating shaft as a reference to measure a positioning error of each rotational angle position of the actuator output shaft and create error correction data for the actuator output shaft for each of the rotational angle positions of the motor rotating shaft;
• detecting a rotational position of the motor rotating shaft;
• using the error correction data to determine an error-correction value allocated to the detected rotational position;
• computing the speed of the motor rotating shaft from a value obtained from using the error-correction value to correct the rotational position, or, alternatively, correcting the speed of the motor rotating shaft calculated from the rotational position on the basis of the error-correction value;
• and
• using the determined speed as a speed feedback value for feedback control of the actuator output shaft.