Patent classifications
G11B5/55
ACTUATOR BLOCK HAVING DUAL SENSORS FOR DETECTING VIBRATION ON MAGNETIC DISK DEVICE
According to one embodiment, a magnetic disk device includes an actuator assembly including an actuator block including a rotatable bearing unit, a plurality of heads movably supported by the actuator assembly, a first sensor provided to the actuator block, and a second sensor provided at a position different from the first sensor.
Data storage device suspension strut damping system
A data storage device can employ a gimbal tongue flexure suspended from a load beam with a transducing head mounted to the gimbal tongue flexure. The transducing head can be separated from a magnetic recording medium by an air bearing. At least one active or non-active damper may be positioned on a strut of the gimbal tongue flexure.
Compensation for nonlinearity in servo patterns
A method according to one embodiment includes generating a y-position estimate based on a servo readback signal, and determining a nonlinearity-correction value corresponding to the y-position estimate. The method further includes adjusting the y-position estimate using the nonlinearity-correction value. A computer program product for compensating for nonlinearity in a timing based servo pattern according to another embodiment includes a computer readable storage medium having program instructions embodied therewith. The program instructions are readable and/or executable by a controller to cause the controller to perform the foregoing method. An apparatus according to another embodiment includes a controller configured to perform the foregoing method.
Magnetic tape apparatus
A magnetic tape apparatus, in which an intensity ratio of peak intensity of diffraction peak of (110) plane with respect to peak intensity of diffraction peak of (114) plane of a hexagonal ferrite crystal structure obtained by XRD analysis of the magnetic layer by In-Plane method is 0.5 to 4.0, a vertical squareness ratio of the magnetic tape is 0.65 to 1.00, a reading element unit includes a plurality of reading elements each of which reads data by a linear scanning method from a specific track region including a reading target track in a track region included in the magnetic tape, and an extraction unit performs a waveform equalization process according to a deviation amount between positions of the magnetic tape and the reading element unit, with respect to each reading result for each reading element, to extract data derived from the reading target track from the reading result.
MINIMIZATION OF THERMAL MAGNETORESISTIVE OFFSET CHANGE
Provided herein is an apparatus including a disk drive base, wherein the disk drive base includes a first metal composition with a first CTE (coefficient of thermal expansion). A disk drive cover is attached to the disk drive base, wherein the disk drive cover includes a second metal composition with a second CTE that are different from the first metal composition and the first CTE. An arm is connected to a reader and a writer, wherein the arm is coupled to the disk drive base, the reader and the writer are separated by a distance, and the distance affects an MR (magnetoresistive) offset. In response to temperature changes between 0 C. and 60 C., the first material and the second material expand and contract comparably and proportionally. In further response to the temperature changes between 0 C. and 60 C., a change in the MR offset is less than 10% or a preferably defined range of a track pitch on a recording medium attached to the disk drive base.
Two-motor co-located gimbal-based dual stage actuation disk drive suspensions with motor stiffeners
Various embodiments concern a dual stage actuation flexure. The dual stage actuation flexure comprises a flexure having a gimbal. The gimbal comprising a pair of spring arms, a tongue between the spring arms, and a pair of linkages respectively connecting the pair of spring arms to the tongue. The dual stage actuation flexure further comprises a pair of motors mounted on the gimbal and a pair of stiffeners respectively mounted on the motors. The dual stage actuation flexure further comprises a slider mounting. Electrical activation of the motors bends the pair of linkages to move the slider mounting about a tracking axis while the stiffeners limit the degree of bending of the motors during the electrical activation.
Data storage device computing notch filters for multiple temperatures
A data storage device is disclosed comprising a head actuated over the disk. A first notch filter is calibrated at a first temperature, and a second notch filter is computed for a second temperature based on the first notch filter and a first delta temperature between the first temperature and the second temperature. The second notch filter is computed by transforming a continuous-time transfer function of the first notch filter adjusted by the first delta temperature into a discrete-time transfer function of the second notch filter.
Read from a non-trimming portion of a data track written to magnetic tape
An example tape drive includes a magnetic tape head, an actuator, and a controller. The magnetic tape head includes a data write element to write a data track including data onto magnetic tape. The data track includes a non-trimming portion and a trimmable portion. The magnetic tape head also includes a data read element to read the data written to the non-trimming portion of the data track to verify the accuracy of the data. The controller positions the magnetic tape head via the actuator to allow (i) the data write element to write the first data track, and (ii) the data read element to read the second portion of the first data track. From the read data, a determination may be made as to whether the data was written to the non-trimming portion of the data track with a threshold level of accuracy.
Concurrent logging of data layers within a tape storage device
Concurrent standard/high resolution logging of critical performance metrics and functional data for various functional areas including servo system, dataflow, channel, read/write, speed matching, and error recovery is achieved by segregating one or more rows of the tape map array for the purpose of logging only high resolution data. As performance data is logged to the standard resolution tape map by wrap and regional offset down tape, the reserved high resolution row logs data sequentially in the order it was processed on magnetic tape and not by its position on magnetic tape. The high-resolution performance data is concurrently logged with normal-resolution performance data as a supporting view with more detailed tape processing data should the normal-resolution performance data have inconclusive or insufficient content. High-resolution storage is structured for shorter regional logging or per-dataset logging of critical performance metrics and functional data, referred to herein as performance data.
Calibrating elevator actuator for disk drive
A data storage device is disclosed comprising a first disk comprising a first disk surface, a second disk comprising a second disk surface, an elevator actuator configured to actuate a head along an axial dimension relative to the first and second disks, a radial actuator configured to actuate the head radially over the first disk surface or the second disk surface, and a position sensor configured to generate a sinusoidal sensor signal representing a position of the head along the axial dimension. A crashstop_offset along the axial dimension is measured from a crashstop position of the elevator actuator to a zero crossing of the sinusoidal sensor signal.