System for fast center calibration of a tape drive for a flangeless tape path
AssigneeInternational Business Machines Corporation
InventorsNhan X. Bui, Reed A. Hancock, Randy C. Inch
Life of this patent
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Abstract
A servo system according to one embodiment includes at least one servo sensor for sensing a lateral position of a magnetic head with respect to at least one defined servo track of a longitudinal tape; a fine actuator configured to translate the magnetic head laterally with respect to the longitudinal tape; a coarse actuator configured to translate the fine actuator laterally with respect to the longitudinal tape; and a servo control. The servo control is configured to perform various operations that may be used to estimate a midpoint of lateral tape excursion of a flangeless tape path for calibrating a tape drive. Additional systems are also presented.
Claims15
A servo system, comprising:
- at least one servo sensor for sensing a lateral position of a magnetic head with respect to at least one defined servo track of a longitudinal tape;
- a fine actuator configured to translate the magnetic head laterally with respect to the longitudinal tape;
- a coarse actuator configured to translate the fine actuator laterally with respect to the longitudinal tape;
- and
- a servo control configured to:
- sense a first servo sensor of the at least one servo sensor while the longitudinal tape is moved in a first direction;
- determine position error between the magnetic head and a desired position related to the at least one defined servo track;
- provide signals to operate the fine actuator to translate the magnetic head laterally in a manner to reduce the determined position error;
- calculate a first average position of the magnetic head for at least one first run-out cycle while the longitudinal tape is moved in the first direction;
- calculate a first offset of the magnetic head while the longitudinal tape is moved in the first direction based on a target position and an assumption that the first average position of the magnetic head occurred when the tape was at a top-most position or a bottom-most position of a supply reel;
- operate the coarse actuator to position the coarse actuator substantially at the target position using the first offset and the first average position;
- and
- store the first offset to a memory.
A servo system, comprising:
- at least one servo sensor for sensing a lateral position of a magnetic head with respect tout least one defined servo track of a longitudinal tape;
- a fine actuator configured to translate the magnetic head laterally with respect to the longitudinal tape;
- a coarse actuator configured to translate the fine actuator laterally with respect to the longitudinal tape;
- and
- a servo control configured to:
- provide signals to track-follow the at least one defined servo track;
- calculate a first average position of the magnetic head for at least one first run-out cycle while the longitudinal tape is moved in the first direction;
- calculate a second average position of the magnetic head for at least one second run-out cycle while the longitudinal tape is moved in the first direction;
- calculate a deviation between the first average position and the second average position, the deviation being related to a first actual lateral tape excursion of the at least one defined servo track while the longitudinal tape is moved in the first direction;
- determine whether the first average position of the magnetic head occurred when the tape was at a top-most position or a bottom-most position of a supply reel using the first actual lateral tape excursion;
- calculate a first offset of the magnetic head while the longitudinal tape is moved in the first direction based on the first actual lateral tape excursion, a target position, and whether the first average position of the magnetic head occurred when the tape was at a top-most position or a bottom-most position of a supply reel;
- mark the first offset as verified;
- and
- store the first offset to a memory.
Dependencies are inferred from the claim text.