Patent ID: 6903897

Claim:
A method for improving the performance of a rotary actuator in a disk drive, the rotary actuator comprises a voice coil motor (VCM) characterized by a torque parameter, the disk drive comprises a servo control system having a motor driver circuit for receiving a series of command effort signals transmitted based on a first seek profile, and for providing an operating current to the VCM based on the command effort signals for causing a movement of the actuator from a first radial location to a target radial location, the method comprising: recording the series of transmitted command effort signals, and while the actuator is moving: adjusting each recorded command effort signal to account for at least one disk drive influence on the actuator movement; storing the adjusted command effort signals; monitoring the velocity of the moving actuator; calculating an acceleration value corresponding to the moving actuator from the stored command effort signals and the monitored velocity; and adjusting the acceleration value to account for a radial torque parameter variation.