Azimuth Or Skew Patents (Class 360/76)
  • Patent number: 11935570
    Abstract: Techniques for determining a data tape read quality value are disclosed. A data tape system generates a value representing a quality of a data tape based on attributes of the data tape. The system calculates the data quality value using an algorithm based on: (a) a particular data tape error correction value, (b) data tape length value representing a length of data tape traversed during data-processing operations, and (c) a scaling factor. The scaling factor is based on a relationship between the particular data tape error correction value and a rate of degradation of the data tape. The scaling factor may be generated by applying a trained machine learning model to attributes of a data tape. The model generates a scaling factor for a particular data tape based on the attributes of the particular data tape.
    Type: Grant
    Filed: May 26, 2022
    Date of Patent: March 19, 2024
    Assignee: Oracle International Corporation
    Inventors: Robert Olin Wyman, Frank Patrick Abbott, Jr.
  • Patent number: 11482253
    Abstract: Processing hard disk drive (HDD) data track repeatable runout (RRO) compensation data includes, for each read-write head constituent to the HDD, and for each data track on which the read-write head operates, saving RRO compensation data to single-level cell (SLC) area of a NAND memory component, and finalizing the RRO data before processing the next read-write head of the HDD, thereby minimizing the SLC area used. Finalizing the RRO data may include sorting the RRO data for the read-write head in the SLC area, moving the sorted RRO data from the SLC area to triple-level cell (TLC) or other higher-level cell area of the NAND, and then erasing the RRO data from the SLC area to free up that memory space, thereby reducing the risk of wearing out the TLC area.
    Type: Grant
    Filed: October 20, 2021
    Date of Patent: October 25, 2022
    Assignee: Western Digital Technologies, Inc.
    Inventors: Zaifeng Chen, Chuanwen Ji
  • Patent number: 11295777
    Abstract: The technology disclosed herein pertains to a system and method for managing off-track retry. An implementation of a method of determining offset direction for read off-track retry includes storing analog to digital converter (ADC) values of data read from a data sector by a data reader in a read channel buffer, calculating an indicator value of the distribution of the ADC values, determining an amount of offset for the data reader based on the indicator value, and moving the data reader by the amount of offset before performing a read retry operation.
    Type: Grant
    Filed: October 30, 2020
    Date of Patent: April 5, 2022
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Xiong Liu, Quan Li
  • Patent number: 10325619
    Abstract: A method of forming a recording head for use with a data storage medium in a data storage device. The method includes forming first and second writers of different target geometries. A first recording measurement is performed on one or more storage media using the first writer. A second recording measurement is performed on the one or more storage media using the second writer. Based on a comparison of the first and second recording measurements to a predetermined quantity, either the first writer or the second writer is selected to be operational in the data storage device.
    Type: Grant
    Filed: November 15, 2017
    Date of Patent: June 18, 2019
    Assignee: Seagate Technology LLC
    Inventors: Kurt Wiesen, Javier Guzman, Joseph Mundenar, Michael Conover
  • Patent number: 10304489
    Abstract: 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.
    Type: Grant
    Filed: June 29, 2018
    Date of Patent: May 28, 2019
    Inventors: Carl R. Hoerger, Geoffrey Stiles, Martin Dyer, Geoffrey Spratt, Jeffrey S. McAllister, Malcolm Grimwood
  • Patent number: 10255933
    Abstract: A method of forming a recording head for use with a data storage medium in a data storage device. The method includes forming first and second writers of different target geometries. A first recording measurement is performed on one or more storage media using the first writer. A second recording measurement is performed on the one or more storage media using the second writer. Based on a comparison of the first and second recording measurements to a predetermined quantity, either the first writer or the second writer is selected to be operational in the data storage device.
    Type: Grant
    Filed: November 15, 2017
    Date of Patent: April 9, 2019
    Assignee: Seagate Technology LLC
    Inventors: Kurt Wiesen, Javier Guzman, Joseph Mundenar, Michael Conover
  • Patent number: 9805752
    Abstract: A storage device includes a storage controller that controls a writer to generate a magnetic field at an air-bearing surface (ABS) of a storage medium and to selectively alter a strength of the magnetic field by a predetermined amount when writing data to select data tracks on the storage medium.
    Type: Grant
    Filed: November 11, 2015
    Date of Patent: October 31, 2017
    Assignee: SEAGATE TECHNOLOGY LLC
    Inventors: Jung Min Yoon, Jae Myung Chung, Hwajun Kim
  • Patent number: 9633681
    Abstract: In one embodiment, a method includes computing more than one skew estimate within each timing-based servo (TBS) frame. Each skew estimate is related to an estimated position of a magnetic tape read head in relation to a magnetic tape medium. In another embodiment, a system includes a hardware processor and logic integrated with and/or executable by the hardware processor. The logic is configured to cause the hardware processor to compute an initial skew estimate based on longitudinal position (LPOS) sync-pattern detection flags detected using servo channels which process at least two readback signals, with the proviso that the LPOS sync-pattern detection flags are only used to compute the initial skew estimate. The logic is also configured to compute more than one skew estimate within each TBS frame thereafter, each skew estimate being related to an estimated position of a magnetic tape read head in relation to a magnetic tape medium.
    Type: Grant
    Filed: November 5, 2015
    Date of Patent: April 25, 2017
    Assignee: International Business Machines Corporation
    Inventors: Giovanni Cherubini, Simeon Furrer, Robert A. Hutchins, Mark A. Lantz
  • Patent number: 9626993
    Abstract: A computer program product according to one embodiment includes a computer readable storage medium having program instructions embodied therewith, the program instructions executable by a controller of a data storage device to cause the controller to perform a method including, determining, by the controller, a test skew gain of a coil using skew information from a servo subsystem of the controller; comparing, by the controller, the test skew gain to a stored reference gain; and taking an action, by the controller, in response to the comparing of the test skew gain to the reference gain.
    Type: Grant
    Filed: September 16, 2015
    Date of Patent: April 18, 2017
    Assignee: International Business Machines Corporation
    Inventors: David H. F. Harper, Randy C. Inch
  • Patent number: 9564161
    Abstract: Embodiments include methods, systems and computer program products for controlling a lateral position of a tape head of a magnetic tape drive. Aspects include determining a first servo signal by reading position marks from a first servo band on a magnetic tape using a first sensor and determining a second servo signal by reading position marks from a second servo band on the magnetic tape using a second sensor. Aspects also include delaying the first servo signal relative to the second servo signal by a delay and calculating an average signal based on the first and the delayed second servo signal. Aspects further include determining servo information from the average signal indicative of a deviation of the lateral position of the tape head from an ideal lateral position of the tape head and controlling the tape head to adjust its lateral position such that the deviation is decreased.
    Type: Grant
    Filed: November 10, 2015
    Date of Patent: February 7, 2017
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Giovanni Cherubini, Simeon Furrer, Mark A. Lantz, Angeliki Pantazi
  • Patent number: 9214164
    Abstract: In one general embodiment, an apparatus includes a magnetic head. The magnetic head has a first portion and a second portion, the first portion and the second portion together providing a tape bearing surface. The first portion has an opening at least partially encircling the second portion. The second portion has at least one array of transducers. A longitudinal axis of each of the at least one array is defined between opposite ends thereof. The longitudinal axis of each of the at least one array of transducers is oriented at an angle relative to a line oriented orthogonally to the intended direction of tape travel thereacross, the angle being between 0.2° and about 10°.
    Type: Grant
    Filed: September 16, 2013
    Date of Patent: December 15, 2015
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Calvin S. Lo
  • Patent number: 9142759
    Abstract: A magnetic memory device comprises a first electrode, a second electrode, a laminated structure comprising plural first magnetic layers being provided between the first electrode and the second electrode, a second magnetic layer comprising different composition elements from that of the first magnetic layer and being provided between plural first magnetic layers, a piezoelectric body provided on a opposite side to a side where the first electrode is provided in the laminated structure, and a third electrode applying voltage to the piezoelectric body and provided on a different position from a position where the first electrode is provided in the piezoelectric body.
    Type: Grant
    Filed: June 20, 2014
    Date of Patent: September 22, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hirofumi Morise, Hideaki Fukuzawa, Akira Kikitsu, Yoshiaki Fukuzumi
  • Publication number: 20150131180
    Abstract: An apparatus for operating a tape storage device comprises a first tape skew determination unit for providing a first tape skew value concerning a skew of a tape in the tape storage device, and a second tape skew determination unit for providing a second tape skew value concerning the skew of the tape. An actuator adjusts one or more of a rotational orientation of a tape head of the tape storage device which tape head is provided for reading and/or writing data from/to the tape, and a motion direction of the tape dependent on the first tape skew value and the second tape skew value.
    Type: Application
    Filed: April 24, 2013
    Publication date: May 14, 2015
    Inventors: Giovanni Cherubini, Jens Jelitto, Angeliki Pantazi
  • Patent number: 9019646
    Abstract: An apparatus includes a write element configured to apply a magnetic field to write data on a portion of a heat-assisted magnetic recording media in response to an energizing current. An energy source is configured to heat the portion of the media being magnetized by the write element. A preheat energizing current is applied to the write element during an interval before writing the data to the portion of the media. The preheat energizing current does not cause data to be written to the media and brings at least one of the write element and driver circuitry into thermal equilibrium prior to writing the data on the portion.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: April 28, 2015
    Assignee: Seagate Technology LLC
    Inventors: Tim Rausch, Jon D. Trantham, John West Dykes, Housan Dakroub, Charles Paul Henry, Edward Charles Gage, Raul Horacio Andruet, James Gary Wessel, James Dillon Kiely, Bruce Douglas Buch, Barmeshwar Vikramaditya
  • Patent number: 9013826
    Abstract: In response to determining that a first write operation is to be performed on a portion of tape, writing data to a data track with a tape head element spacing at a nominal value. A tape width of one or more tape positions at which data is written is recorded. In another aspect, a tape width value associated with a tape is retrieved. A current tape width value associated with the tape is determined, and the tape head element spacing is set based on a difference between the retrieved tape width value and the determined current tape width value.
    Type: Grant
    Filed: December 18, 2013
    Date of Patent: April 21, 2015
    Assignee: International Business Machines Corporation
    Inventor: Philipp Herget
  • Patent number: 9007712
    Abstract: The present invention, in some embodiments, relates to magnetic heads having modules with arrays of transducers able to read and/or write while the arrays are positioned at different angles relative to a magnetic medium, thereby enabling reading and/or writing in more than one data storage format. An apparatus according to one embodiment includes at least two modules, each of the modules having an array of N+1 transducers. Axes of the arrays are oriented about parallel to each other. N of the N+1 transducers of a first array of a first of the modules are about aligned with N of the N+1 transducers of a second array of a second of the modules when the axes of the arrays are tilted at a first angle between about 0.1° and about 10°.
    Type: Grant
    Filed: December 16, 2013
    Date of Patent: April 14, 2015
    Assignee: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Calvin S. Lo
  • Patent number: 8988801
    Abstract: A method for measuring noise of a magnetic head includes setting a plurality of threshold values, applying bias current or voltage to a read element of the magnetic head, applying an external transverse magnetic field to the magnetic head, amplifying output signal from the read element to produce an amplified signal, filtering the amplified signal to produce a filtered signal, generating an enable signal for each threshold value in a predetermined time window by a counting control means with input signals which include the filtered signal and the threshold value, measuring the cumulative time duration of each enable signal, making an amplitude-duration distribution according to the cumulative time durations and the threshold values, calculating a plurality of parameters according to the amplitude-duration distribution and analyzing the parameters with a plurality of predetermined criteria to determine the defects of the magnetic head.
    Type: Grant
    Filed: October 6, 2014
    Date of Patent: March 24, 2015
    Assignee: SAE Magnetics (H.K.) Ltd.
    Inventors: Wahchun Chan, Tszlok Cheng, Shengqiang Chen
  • Patent number: 8964325
    Abstract: A magnetic disk device according to an embodiment includes a head and a disk with a recording surface, the head including a reader configured to perform data reading, and a writer configured to write data. A method of correcting a read/write offset, according to the embodiment, is applied to the above magnetic disk device. This method includes reconstructing position data read by the reader, using a spline function, and correcting a read/write offset due to the distance between the writer and the reader, using the reconstructed position data.
    Type: Grant
    Filed: March 5, 2014
    Date of Patent: February 24, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Tomoyoshi Yamada
  • Patent number: 8929008
    Abstract: Systems and methods for testing magnetic media disks during manufacturing using sliders with temperature sensors are provided. One such method involves scanning a surface of a selected disk of a plurality of magnetic media disks using a slider including a magnetic transducer and a temperature sensor, counting a number of the surfaces scanned, determining, during the scanning, whether a threshold crossing event has occurred by determining whether a signal from the temperature sensor signal is not within a preselected range, counting, during the scanning, a number of threshold crossing events, storing, if the number of threshold crossing events is greater than a preselected events limit, the number of surfaces scanned, stopping, if the number of surfaces scanned is greater than a surfaces scanned threshold, the scanning, and returning, if the number of surfaces scanned is less than or equal to the surfaces scanned threshold, to scan a next selected disk.
    Type: Grant
    Filed: June 26, 2013
    Date of Patent: January 6, 2015
    Assignee: WD Media, LLC
    Inventors: Thomas A. O'Dell, Balvinder Singh
  • Patent number: 8896960
    Abstract: A servo track has servo pattern frames including two pairs of parallel transitions, the transitions of each pair spaced apart an equal distance, the first pair at an azimuth angle, the second pair at the opposite azimuth angle. A servo channel receives signals at first times corresponding to a servo read head detecting the transitions of the first pair of parallel transitions of a servo pattern frame, and second times corresponding to the servo read head detecting the transitions of the second pair of parallel transitions. The servo channel determines a relative lateral movement and velocity between the tape and the tape head based on respective functions of the ratio (TD?TC)/(TB?TA), distance d, and constants proportional to the azimuth angle and the trajectory angle.
    Type: Grant
    Filed: October 9, 2013
    Date of Patent: November 25, 2014
    Assignee: International Business Machines Corporation
    Inventors: Allen K. Bates, Nhan X. Bui, Nils Haustein, Stephen L. Schwartz, Daniel J. Winarski
  • Patent number: 8891198
    Abstract: In a method for operating a tape storage device comprising a tape head for reading and/or writing data from/to a tape in the tape storage device, a first tape skew value concerning a skew of the tape is determined and the first tape skew value is converted into a first skew control signal by means of a skew feedback controller. A second tape skew value concerning the skew of the tape is determined, and the second tape skew value is converted into a second skew control signal by a feed-forward controller. At least one compensation signal for the second skew control signal is determined, and at least one of a rotational orientation of the tape head and a tape motion direction of the tape is controlled dependent on the second skew control signal and the compensation signal in case the first skew control signal fails.
    Type: Grant
    Filed: July 22, 2013
    Date of Patent: November 18, 2014
    Assignee: International Business Machines Corporation
    Inventors: Nhan X. Bui, Giovanni Cherubini, Jens Jelitto, Angeliki Pantazi, Kazuhiro Tsuruta
  • Publication number: 20140334033
    Abstract: Apparatuses are configured to addresses tape dimensional stability (TDS) via small rotations about the quasi-static tilt angle and read and/or write data in non-legacy formats. Products such as tape media products are also presented.
    Type: Application
    Filed: May 8, 2013
    Publication date: November 13, 2014
    Applicant: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Calvin S. Lo
  • Publication number: 20140327987
    Abstract: In one general embodiment, an apparatus includes at least two modules, each of the modules having an array of transducers, wherein the at least two modules are fixed relative to each other, wherein an axis of each array is defined between opposite ends thereof, wherein the axes of the arrays are oriented about parallel to each other, wherein the array of a first of the modules is offset from the array of a second of the modules in a first direction parallel to the axis of the array of the second module such that the transducers of the first module are about aligned with the transducers of the second module in an intended direction of tape travel thereacross; and a mechanism for orienting the modules about an axis orthogonal to the plane in which the arrays reside to control a transducer pitch presented to a tape.
    Type: Application
    Filed: May 1, 2013
    Publication date: November 6, 2014
    Applicant: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Philipp Herget, Calvin S. Lo
  • Publication number: 20140327984
    Abstract: An apparatus according to one embodiment includes a magnetic head, the magnetic head having: a tape bearing surface having a first edge oriented perpendicular to an intended direction of tape travel thereacross; and an array of transducers in and/or adjacent the tape bearing surface, wherein a longitudinal axis of the array is defined between opposite ends thereof, wherein the longitudinal axis of the array of transducers is oriented at an angle relative to the first edge, the angle being between greater than 0.2° and about 10°.
    Type: Application
    Filed: May 1, 2013
    Publication date: November 6, 2014
    Applicant: International Business Machines Corporation
    Inventors: Robert G. Biskeborn, Calvin S. Lo
  • Publication number: 20140268408
    Abstract: A device for recording and/or reading data to and/or from a magnetic tape includes a read/write head which has a first device set including a first plurality of magnetic data write and/or read elements and a second device set including a second plurality of magnetic data write and/or read elements. The device also includes a lateral positioning actuator and an azimuth actuator. The lateral positioning actuator and azimuth actuator are used together to position both device sets on the magnetic tape. The lateral positioning actuator laterally positions the read/write head such that during write and/or read operations the first and second pluralities of magnetic data write and/or read elements align laterally to first and second pluralities of recordable and/or readable data tracks on the magnetic tape. The azimuth actuator rotates the read/write head about an azimuthal angle. such that the elements align to lateral spacings.
    Type: Application
    Filed: March 13, 2013
    Publication date: September 18, 2014
    Applicant: ORACLE INTERNATIONAL CORPORATION
    Inventors: Darryl Wayne Yeakley, William J. Vanderheyden, Steven Gregory Trabert
  • Publication number: 20140268409
    Abstract: Provided are a computer program product, system, and method for determining a skew error signal (SES) offset used to determine an SES to adjust heads in a drive unit. A determination is made of a first difference in a first orientation with respect to a direction of movement of the recordable storage media based on first and second position information read by first and second servo read elements on a first head. A determination is made of a second difference in a second orientation with respect to the direction of movement of the recordable storage media based on third and fourth position information read by the first servo read element and a third servo read element on a second head. An offset, calculated based on the determined first and second difference, is used to generate an error signal to adjust the first and second heads.
    Type: Application
    Filed: May 28, 2014
    Publication date: September 18, 2014
    Applicant: International Business Machines Corporation
    Inventors: Nhan X. Bui, Angeliki Pantazi, Tomoko Taketomi, Kazuhiro Tsuruta
  • Patent number: 8830620
    Abstract: A method for reducing skew angle variation range in a shingled magnetic recording system, the method including the following steps: 1) determining whether a starting magnetic track is in an inner recording zone, if yes, the process proceeds to step (2), otherwise the process proceeds to step (4); 2) using an inner writing corner to start shingled magnetic recording at a starting track; 3) using a shingled magnetic method to write rest magnetic tracks sequentially by the inner writing corner, keeping a writing pole moving in a direction from an inner recording zone to an outer recording zone; 4) determining whether the starting magnetic track is in the outer recording zone; 5) using an outer writing corner to start shingled magnetic recording at the starting track; and 6) using the shingled magnetic method to write the rest magnetic tracks sequentially by the outer writing corner.
    Type: Grant
    Filed: December 2, 2013
    Date of Patent: September 9, 2014
    Assignee: Huazhong University of Science and Technology
    Inventors: Shu Xu, Bo Liu, Jincai Chen
  • Patent number: 8824092
    Abstract: The relative trajectory of a transducer head over bit-patterned media (BPM) may be skewed with respect to a down-track direction on the media (i.e., skew error). In order to resolve the skew error, the presently disclosed technology measures the skew error without adding additional patterning on the media. A detector circuit detects a sequential series of data bits on a storage media. The sequential series of data bits alternate between at least two tracks on the storage media. The sequential series of data bits are sent to a timing circuit, which sets a time stamp indicating when each data bit is received using, for example, a delay chain or a voltage ramp. A time elapsed between receiving a first data bit, a second data bit, and a third data bit is tracked. Transducer head skew is adjusted based on a signal containing the time elapsed between the bits.
    Type: Grant
    Filed: November 8, 2010
    Date of Patent: September 2, 2014
    Assignee: Seagate Technology LLC
    Inventors: Sundeep Chauhan, Barmeshwar Vikramaditya
  • Patent number: 8810956
    Abstract: A method for accurately adjusting skew in the presence of tape motion includes performing a calibration run of magnetic tape in a tape drive. During the calibration run, the method records skew readings at selected intervals. The method then finds a range associated with the skew readings, such as by finding a high and low skew reading. The method then finds a center point of the range, and a difference between the center point and a desired center point. The method applies the difference to each recorded skew reading to generate a target skew reading for each recorded skew reading. The method generates a skew error signal that reflects the difference between each recorded skew reading and each corresponding target skew reading. The skew error signal will generally be consistent even as the tape moves, thereby allowing a technician to easily adjust and optimize the skew.
    Type: Grant
    Filed: July 30, 2012
    Date of Patent: August 19, 2014
    Assignee: International Business Machines Corporation
    Inventors: Randy Clark Inch, Kevin Bruce Judd
  • Patent number: 8810941
    Abstract: Selection of disk drive data tracks for the location of reserved area include providing a media disk with data tracks comprising a user data region. A location is assessed on the media disk with a highest frequency of adjacent track interference and far track interference-refresh potential. The location is then configured to be a reserved area where no user data is written. The reserved area has parameters that are read out first before the disk drive enters an operation enabled state for user interface.
    Type: Grant
    Filed: July 10, 2012
    Date of Patent: August 19, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Toshiroh Unoki, Takeshi Shikama
  • Patent number: 8792200
    Abstract: A disk drive is disclosed comprising a disk, and a head actuated over the disk, the head comprising a read element radially offset from a write element. A temperature is measured, and an operating write offset is generated based on the measured temperature. Data is written to a target radial location on the disk by radially offsetting the write element based on the operating write offset. An operating read offset is generated based on the target radial location on the disk, and the data is read from the disk by radially offsetting the read element based on the operating read offset.
    Type: Grant
    Filed: September 23, 2013
    Date of Patent: July 29, 2014
    Assignee: Western Digital Technologies, Inc.
    Inventors: Zong Yuan Tam, Chek Seng Ching
  • Patent number: 8780486
    Abstract: Provided are a computer program product, system, and method for determining a skew error signal (SES) offset used to determine an SES to adjust heads in a drive unit. A determination is made of a first difference in a first orientation with respect to a direction of movement of the recordable storage media based on first and second position information read by first and second servo read elements on a first head. A determination is made of a second difference in a second orientation with respect to the direction of movement of the recordable storage media based on third and fourth position information read by the first servo read element and a third servo read element on a second head. An offset, calculated based on the determined first and second difference, is used to generate an error signal to adjust the first and second heads.
    Type: Grant
    Filed: July 10, 2012
    Date of Patent: July 15, 2014
    Assignee: International Business Machines Corporation
    Inventors: Nhan X. Bui, Angeliki Pantazi, Tomoko Taketomi, Kazuhiro Tsuruta
  • Patent number: 8780487
    Abstract: Tuning a skew between a read head and a write head, may include setting a center value of a track according to a track density of a storage medium; writing data having a certain pattern to at least one target track and at least two tracks adjacent to the target track, while following the center value of the track; reading the data having a certain pattern from the target track by using a plurality of off track values in an off track range based on the center value of the track; and detecting an off track value having a minimum error occurrence number among error occurrence numbers with respect to the read data having a certain pattern corresponding to each of the plurality of off tracks, as an optimum off track value of the target track.
    Type: Grant
    Filed: June 29, 2012
    Date of Patent: July 15, 2014
    Assignee: Seagate Technology LLC
    Inventors: Jun Bum Park, Moon Choi Park
  • Publication number: 20140192437
    Abstract: A head rotator assembly (22) for positioning a head (20) of a tape drive (10) relative to a storage tape includes a head supporter (230) and a supporter mover assembly (232). The head supporter (230) is coupled to and supports the head (20). The supporter mover assembly (232) selectively rotates a portion of the head supporter (230) about an axis (241) to move the head (20) in an azimuth direction relative to the storage tape as the storage tape moves over the head (20). The head rotator assembly (22) further includes a controller (16) that controls movement of the supporter mover assembly (232) based at least partially on a positioning signal. The supporter mover assembly (232) can include a first actuator (234A) and a first lever (236A). The first actuator (234A) moves the first lever (236A) to rotate the head supporter (230) so that the head (20) moves in the azimuth direction. The first actuator (234A) can include a piezoelectric element.
    Type: Application
    Filed: March 13, 2014
    Publication date: July 10, 2014
    Applicant: Quantum Corporation
    Inventors: Ashok B. Nayak, Turguy Goker, Ming-Chih Weng, James Mark Decot
  • Patent number: 8711512
    Abstract: A servo write apparatus, comprising a first servo write head configured to only encode a single first magnetic dibit onto a magnetic information storage medium, wherein the first magnetic dibit comprises a first azimuthal slope. The servo write apparatus further comprises a second servo write head configured to encode one or more second magnetic dibits onto a magnetic information storage medium, wherein the second magnetic dibit comprises a second azimuthal slope, wherein the first azimuthal slope differs from the second azimuthal slope.
    Type: Grant
    Filed: October 24, 2011
    Date of Patent: April 29, 2014
    Assignee: International Business Machines Corporation
    Inventor: William John Kabelac
  • Patent number: 8705198
    Abstract: An implementation of a system disclosed herein provides a method of compensating for a change in write position of a recording head due to a change in an operating condition of the recording head.
    Type: Grant
    Filed: August 27, 2012
    Date of Patent: April 22, 2014
    Assignee: Seagate Technology LLC
    Inventors: Ravi Hebbar, Peter Stuart Harllee, III
  • Patent number: 8643975
    Abstract: Method for operating a storage device with a tape and a head which is operable to read and/or write data from and respectively to the tape. The tape is moveable in a predetermined longitudinal direction. At least two consecutive current lateral tape positions of the tape with respect to a predetermined reference point are determined at a predetermined longitudinal capture position. A tape skew of the tape is determined dependent on the at least two determined lateral positions. The tape skew represents an angle between a current tape motion direction of the tape and the longitudinal direction. A skew control signal is determined dependent on the determined tape skew. A rotational head position of the head is controlled dependent on the skew control signal to align the head to the current tape motion direction in such a way that the head is operable to read and/or write data.
    Type: Grant
    Filed: December 17, 2010
    Date of Patent: February 4, 2014
    Assignee: International Business Machines Corporation
    Inventors: Giovanni Cherubini, Jens Jelitto, Angeliki Pantazi
  • Patent number: 8638523
    Abstract: A system provides tape having at least one longitudinal data track and a tape head operative to move along a single axis line lateral to the data track. The storage tape moves across the tape head. The tape head moves along the axis line such that a write element of the tape head intersects the data track and writes data to a section of the data track. A controller determines that the storage tape is skewed. In response to determining that the storage tape is skewed, the controller determines a position along the axis line and a time to move the tape head such that the read elements intersects the section of the data track. At the determined time, the tape head pauses writing of data and moves to the position along the axis line. The tape head reads the section of the data track to verify the written data.
    Type: Grant
    Filed: July 2, 2012
    Date of Patent: January 28, 2014
    Assignee: International Business Machines Corporation
    Inventor: David H. Harper
  • Publication number: 20140016226
    Abstract: Provided are a computer program product, system, and method for determining a skew error signal (SES) offset used to determine an SES to adjust heads in a drive unit. A determination is made of a first difference in a first orientation with respect to a direction of movement of the recordable storage media based on first and second position information read by first and second servo read elements on a first head. A determination is made of a second difference in a second orientation with respect to the direction of movement of the recordable storage media based on third and fourth position information read by the first servo read element and a third servo read element on a second head. An offset, calculated based on the determined first and second difference, is used to generate an error signal to adjust the first and second heads.
    Type: Application
    Filed: July 10, 2012
    Publication date: January 16, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Nhan X. Bui, Angeliki Pantazi, Tomoko Taketomi, Kazuhiro Tsuruta
  • Patent number: 8625230
    Abstract: According to one embodiment, a position demodulator includes a demodulator, a phase corrector, and a position demodulating module. The demodulator demodulates a first demodulated signal and a second demodulated signal having a phase difference of 90 degrees from the first demodulated signal as a result of discrete Fourier transform operation on a read signal of a null servo pattern recorded in a servo area of a medium read out by a head. The phase corrector carries out correction to tilt respective vectors of the first demodulated signal and the second demodulated signal represented on a phase plane by a predetermined angle. The position demodulating module demodulates a positional signal for determining the position of the core of the head based on the first demodulated signal and the second demodulated signal corrected by the phase corrector.
    Type: Grant
    Filed: February 9, 2012
    Date of Patent: January 7, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tatsuhiko Kosugi, Kazuhiko Takaishi, Takeshi Hara, Hiroshi Oyabu
  • Patent number: 8619384
    Abstract: A servo track has identical servo pattern frames including two pairs of parallel magnetic transitions, the transitions of each pair spaced apart an equal distance, the transitions of the first pair at an azimuth angle to the longitudinal axis of the tape, the transitions of the second pair at an opposite azimuth angle. A servo channel receives signals at first times corresponding to when a servo read head detects the first and second transitions of the first pair of parallel transitions of a servo pattern frame, and second times corresponding to when the servo read head detects the first and second transitions of the second pair of parallel transitions. The servo channel determines a relative lateral movement and velocity between the tape and the tape head based on the azimuth angle and the ratio of the difference of the first and the difference of the second times.
    Type: Grant
    Filed: July 18, 2012
    Date of Patent: December 31, 2013
    Assignee: International Business Machines Corporation
    Inventors: Allen K. Bates, Nhan X. Bui, Nils Haustein, Stephen L. Schwartz, Daniel J. Winarski
  • Publication number: 20130335856
    Abstract: SMR disk drives are described that adjust track pitch or magnetic write width to compensate for external temperature effects. In one embodiment track pitch is increased when the media temperature increases. The temperature of magnetic media during write operations can be determined from the drives' temperature sensor. In other embodiments track pitch is adjusted based on the magnetic write width (MWW) which is determined from read-back testing of previously written data tracks. In an alternative embodiment, the width of the MWW is adjusted instead of the track pitch. The various factors that affect the MWW that can be used to increase or decrease the MWW, including write current characteristics and when available thermal-assistance parameters.
    Type: Application
    Filed: June 14, 2012
    Publication date: December 19, 2013
    Inventors: Hiroyasu Tanabe, Hideki Zaitsu, Kyo Akagi, Naoto Ito
  • Patent number: 8611038
    Abstract: A tape drive system according to one embodiment includes a magnetic head having at least one servo sensor; a tape motion controller; a fine actuator; a skew actuator; a coarse actuator; and a control. The control is configured to perform various operations that help account for vibrations that effect track-following a servo track when operating a tape drive. Additional systems, methods and computer program products are also described.
    Type: Grant
    Filed: June 2, 2011
    Date of Patent: December 17, 2013
    Assignee: International Business Machines Corporation
    Inventors: Nhan X. Bui, Reed A. Hancock, Tomoko Taketomi
  • Publication number: 20130286502
    Abstract: Apparatus for two dimensional data reading. In accordance with some embodiments, a magnetic read element has a plurality of read sensors positioned symmetrically about a pivot point with at least two of the read sensors configured to concurrently read two dimensional user data while being immune to skew angle misalignment.
    Type: Application
    Filed: April 27, 2012
    Publication date: October 31, 2013
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Mehmet Fatih Erden, Jason Gadbois
  • Patent number: 8432634
    Abstract: An apparatus includes plural spaced apart sensors arranged along a direction of motion of a medium, and a processing circuit to receive signals from the sensors, determine a difference of the signals, and identify an error built into the medium based on the difference.
    Type: Grant
    Filed: April 3, 2006
    Date of Patent: April 30, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Jeffrey S. McAllister, Donald J. Fasen, Vernon L. Knowles
  • Patent number: 8331055
    Abstract: A method for monitoring a plurality of servo channels, providing a finite state machine (“FSM”) comprising a single servo channel mode and a combined servo channel mode, and moving a sequential information storage medium comprising a plurality of servo bands across a read/write head comprising a corresponding plurality of servo sensors. The method further asserts an acquisition flag by a servo channel if that servo channel is tracking a servo pattern, and asserts a bit flag by a servo channel if a new LPOS bit is decoded. If at least one acquisition flag is asserted, the method determines if a bit flag is asserted by a servo channel associated with said asserted acquisition flag, and if an acquisition flag and a bit flag are asserted by a servo channel, the method determines a relative positioning of each servo sensor with respect to an associated servo pattern.
    Type: Grant
    Filed: July 9, 2009
    Date of Patent: December 11, 2012
    Assignee: International Business Machines Corporation
    Inventors: Giovanni Cherubini, Robert Allen Hutchins, Jens Jelitto, Melanie Jean Sandberg
  • Publication number: 20120268842
    Abstract: Method for operating a storage device with a tape and a head which is operable to read and/or write data from and respectively to the tape. The tape is moveable in a predetermined longitudinal direction. At least two consecutive current lateral tape positions of the tape with respect to a predetermined reference point are determined at a predetermined longitudinal capture position. A tape skew of the tape is determined dependent on the at least two determined lateral positions. The tape skew represents an angle between a current tape motion direction of the tape and the longitudinal direction. A skew control signal is determined dependent on the determined tape skew. A rotational head position of the head is controlled dependent on the skew control signal to align the head to the current tape motion direction in such a way that the head is operable to read and/or write data.
    Type: Application
    Filed: December 17, 2010
    Publication date: October 25, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Giovanni Cherubini, Jens Jelitto, Angeliki Pantazi
  • Patent number: 8289645
    Abstract: According to one embodiment, there is provided a magnetic disk apparatus having a magnetic disk having magnetic dot lines each including magnetic dots arrayed at equal intervals in a down track direction, and a read/write head which uses a plurality of adjacent magnetic dot lines as one track and sequentially performs read and write on the magnetic dots included in the magnetic dot lines constituting the track, in which the magnetic dots included in each of the magnetic dot lines in each track of the magnetic disk are displaced in the down track direction from the magnetic dots included in the adjacent dot line in the track depending on a possible skew angle between the read/write head and the track so that the magnetic dots are sequentially accessed by the read/write head.
    Type: Grant
    Filed: October 4, 2010
    Date of Patent: October 16, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masatoshi Sakurai, Akira Kikitsu, Kazuto Kashiwagi
  • Patent number: 8194884
    Abstract: Systems, methods, and apparatus, including computer program products, for audio editing are provided. In some implementations, a method is provided. The method includes receiving audio data having a first audio channel and a second audio channel. The audio data is separated, into a plurality of blocks. An amount of misalignment is determined between the first audio channel and the second audio channel for the portion of the audio data in each block using a phase difference between the first and second audio channels for each of a plurality of frequency bands. The first and second channels are aligned using the determined misalignment.
    Type: Grant
    Filed: August 23, 2006
    Date of Patent: June 5, 2012
    Assignee: Adobe Systems Incorporated
    Inventor: David E. Johnston
  • Patent number: 8189285
    Abstract: A servo controller includes a first device that determines an adjusted servo-to-servo skew value. A servo field timer increments a timer value between consecutive servo fields, receives the adjusted servo-to-servo skew value, and adjusts an incremented timer value between the consecutive servo fields based on the adjusted servo-to-servo skew value.
    Type: Grant
    Filed: January 28, 2009
    Date of Patent: May 29, 2012
    Assignee: Marvell International Ltd.
    Inventors: Michael R. Spaur, Raymond A. Sandoval