Patent ID: 6683461
Filing Date: 2004-01-27
Classification: G01D

Abstract:
A calibration system for a servo controlled mechanism containing a position transducer with a repeatable error and being influenced by an external disturbance, comprising:a closed loop having a normal operation and a calibration operation; an input to the closed loop, said input being a normal command during the normal operation and a calibration command during the calibration operation; a calibration system producing the calibration command, measuring the repeatable error during the calibration operating function, storing a characteristic of the measured repeatable error, and injecting a calibration adjustment based on the stored characteristic into the closed loop during the normal operation; and a controller in the closed loop having a sensitivity function that approximates a natural value at the frequency of the position transducer repeatable error and, in absolute value, is lower at the frequencies of the normal command input and of the external disturbance.