Abstract: Systems and methods for improving the accuracy of test measurements involving aggressor tracks written to the disks are provided. One such method involves erasing a circumferential band of a disk, writing a central track on the circumferential band, measuring and storing a first track profile of the central track, writing an aggressor track on each side of the central track at a preselected aggressor track offset from the central track, measuring and storing a track profile of the aggressor tracks at the preselected aggressor track offset, measuring and storing a second track profile of the central track, performing the prior actions exactly n times where n is greater than or equal to 1, determining an estimated distance between the aggressor tracks based on the respective track profiles, determining a selected measurement using the estimated distance between the aggressor tracks, and the first and second track profiles of the central track.

Abstract: Systems and methods for making fast measurements of channel performance metrics such as error margin and off-track recording capability in shingled magnetic recording are provided. One such method involves writing a plurality of shingled tracks on the disk, measuring an off track read capability (OTRC) of each of the plurality of shingled tracks, determining radial endpoints of the measured OTRC for each of the plurality of shingled tracks, determining an approximate radial center for each of the plurality of shingled tracks based on the respective OTRC radial endpoints, and measuring a channel performance metric at a range centered around the approximate radial center for each of the plurality of shingled tracks. In one such case, the channel performance metric involves error margin. One such system includes a processor coupled to a memory, a magnetic transducer, and a test platform, where the processor is configured to perform the method.

Abstract: Systems and methods for improving accuracy of head positioning using existing servo patterns are provided. In one embodiment, a method for improving read head positioning is provided that comprises: writing a series of tracks over a range of read offsets to be calibrated; measuring a set of raw track profiles from the series of tracks; sampling the set of raw track profiles at a series of signal amplitude levels; constructing a reference track profile from the set of sampled track profiles; calculating a set of read offset deltas from each sampled track profile; merging the sets of read offset deltas into a set of average read offset deltas; and converting the set of average read offset deltas into a read offset correction table. A similar method for improving disk write head positioning is also provided which utilizes such a read offset correction table to eventually create write offset correction table.

Abstract: Systems and methods for improving accuracy of head positioning using existing servo patterns are provided. In one embodiment, a method for improving read head positioning is provided that comprises: writing a series of tracks over a range of read offsets to be calibrated; measuring a set of raw track profiles from the series of tracks; sampling the set of raw track profiles at a series of signal amplitude levels; constructing a reference track profile from the set of sampled track profiles; calculating a set of read offset deltas from each sampled track profile; merging the sets of read offset deltas into a set of average read offset deltas; and converting the set of average read offset deltas into a read offset correction table. A similar method for improving disk write head positioning is also provided which utilizes such a read offset correction table to eventually create write offset correction table.

Abstract: Systems and methods for improving accuracy of head positioning using existing servo patterns are provided. In one embodiment, a method for improving read head positioning is provided that comprises: writing a series of tracks over a range of read offsets to be calibrated; measuring a set of raw track profiles from the series of tracks; sampling the set of raw track profiles at a series of signal amplitude levels; constructing a reference track profile from the set of sampled track profiles; calculating a set of read offset deltas from each sampled track profile; merging the sets of read offset deltas into a set of average read offset deltas; and converting the set of average read offset deltas into a read offset correction table. A similar method for improving disk write head positioning is also provided which utilizes such a read offset correction table to eventually create write offset correction table.

Abstract: A system (10) and method for high-speed massive magnetic imaging on a spin-stand (12) is provided. The system (10) includes a spin-stand system (12) for driving a rotational spindle (20) to which a magnetic hard disk (30) is mounted. A magnetic read head (40) reads data from disk (30) and is in electrical communication with a universal head preamplification board (50). The universal head preamplification board (50) outputs readable voltage signals which are transmitted to an oscilloscope (60) for displaying a read-back voltage display (70). The signals are processed by a processing means (90) to generate scanned image data (100) on a display means. The display signals (70) are utilized to calibrate the magnetically read data to account for the eccentricity of the hard disks with respect to the center of rotation of the spin-stand spindle. Whole tracks of hard disk data can be imaged through the process of “track-centering” and “track-following”.

Abstract: A system (10) and method for high-speed massive magnetic imaging on a spin-stand (12) is provided. The system (10) includes a spin-stand system (12) for driving a rotational spindle (20) to which a magnetic hard disk (30) is mounted. A magnetic read head (40) reads data from disk (30) and is in electrical communication with a universal head preamplification board (50). The universal head preamplification board (50) outputs readable voltage signals which are transmitted to an oscilloscope (60) for displaying a read-back voltage display (70). The signals are processed by a processing means (90) to generate scanned image data (100) on a display means. The display signals (70) are utilized to calibrate the magnetically read data to account for the eccentricity of the hard disks with respect to the center of rotation of the spin-stand spindle. Whole tracks of hard disk data can be imaged through the process of “track-centering” and “track-following”.