Patent ID: 6310742
Filing Date: 2001-10-30
Classification: G11B

Abstract:
A method for selectively correcting repeatable runout in a disk drive having a magnetic disk with a plurality of tracks that each have a cylinder address and a plurality of servo wedges, a means for rotating the magnetic disk at a rotation frequency, a transducer head mounted on an actuator, a means for moving the actuator, and a sampled servo controller for reading signals from the transducer head and for providing servo compensation signals to the actuator moving means for positioning the transducer head over the magnetic disk, the method of comprising:determining wedge runout values for each servo wedge of each track;comparing the wedge runout values to a predetermined threshold for identifying over-threshold wedge runout values which exceed the predetermined threshold;storing each of the over-threshold wedge runout values;determining that a servo wedge having an over-threshold wedge runout value is the next wedge to pass under the transducer head; andproviding the over-threshold wedge runout value to the sampled servo controller.