Patent ID: 7145745

Claim:
A method of compensating for repeatable runout in a disk drive having a data storage disk, a transducer adjacent to the disk, a primary actuator for positioning the transducer over a first range of movement, and a secondary actuator for positioning the transducer over a second range of movement that is less than the first range of movement, the method comprising: estimating a position of the secondary actuator in the second range of movement; reading data from the disk via the transducer; determining a position error signal based on the read data; determining repeatable runout for at least one track on the disk; generating a repeatable runout compensation signal based on the determined repeatable runout; and controlling positioning of the transducer by the primary actuator based on the repeatable runout compensation signal, based on the position error signal, and based on the estimated position of the secondary actuator in the second range of movement to compensate for repeatable runout.