Machine motion trajectory measuring apparatus

A machine motion trajectory measuring apparatus that measures a motion trajectory of a machine apparatus that comprises an actuator and that feeds back a detection position signal output from a position detector that detects a position of the actuator or a position of a driven body and drives the actuator such that a motion trajectory of the driven body follows a command trajectory, the machine motion trajectory measuring apparatus comprising:

• an acceleration sensor to measure acceleration of a motion-trajectory measurement subject and output a result as an acceleration sensor signal;
• a reference acceleration sensor to measure acceleration of a point serving as a reference for trajectory measurement of the motion-trajectory measurement subject and output a result as a reference acceleration sensor signal;
• a sensor signal separator to separate each of the acceleration sensor signal and the reference acceleration sensor signal into two or more frequency bands;
• a detection position signal separator to separate the detection position signal into frequency bands identical to the frequency bands of the sensor signal separator;
• a data calibrator to calibrate the acceleration sensor signal in each of the two or more frequency bands by using the acceleration sensor signal separated by the sensor signal separator, the reference acceleration sensor signal separated by the sensor signal separator, and the detection position signal separated by the detection position signal separator and to obtain a motion trajectory component in each of the two or more frequency bands;
• and
• a motion trajectory calculator to couple the motion trajectory component in each of the two or more frequency bands and output a result as information indicative of the motion trajectory.