Patents by Inventor David H. Harper

David H. Harper has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9424869
    Abstract: Controlling the position of a head within a tape transport system. A track-follow control system (TFCS) includes a controller device for generating a control signal as a function of a position error signal (PES), wherein the PES indicates a difference between the actual and target positions of the head relative to the tape, and an actuator for changing the actual position. The TFCS is adapted to select a controller device configuration from a plurality of configurations dependent on an operating tape speed. The configurations are predetermined depending on a vibration frequency domain profile indicative of environmental vibrations induced to the head and tape to determine the control signal for adjusting an actuator output signal relative to a lateral tape motion signal. The TFCS is also adapted to feed-back a signal depending on a difference of the actuator output signal and the lateral tape motion signal to generate the PES.
    Type: Grant
    Filed: July 17, 2015
    Date of Patent: August 23, 2016
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Armando J. Argumedo, Nhan X. Bui, David H. Harper, Randy C. Inch, Kevin B. Judd, Mark A. Lantz, Angeliki Pantazi, Tomoko Taketomi
  • Publication number: 20150325262
    Abstract: Controlling the position of a head within a tape transport system. A track-follow control system (TFCS) includes a controller device for generating a control signal as a function of a position error signal (PES), wherein the PES indicates a difference between the actual and target positions of the head relative to the tape, and an actuator for changing the actual position. The TFCS is adapted to select a controller device configuration from a plurality of configurations dependent on an operating tape speed. The configurations are predetermined depending on a vibration frequency domain profile indicative of environmental vibrations induced to the head and tape to determine the control signal for adjusting an actuator output signal relative to a lateral tape motion signal. The TFCS is also adapted to feed-back a signal depending on a difference of the actuator output signal and the lateral tape motion signal to generate the PES.
    Type: Application
    Filed: July 17, 2015
    Publication date: November 12, 2015
    Inventors: ARMANDO J. ARGUMEDO, NHAN X. BUI, DAVID H. HARPER, RANDY C. INCH, KEVIN B. JUDD, MARK A. LANTZ, ANGELIKl PANTAZI, TOMOKO TAKETOMI
  • Patent number: 9087539
    Abstract: Controlling the position of a head within a tape transport system. A track-follow control system (TFCS) includes a controller device for generating a control signal as a function of a position error signal (PES), wherein the PES indicates a difference between the actual and target positions of the head relative to the tape, and an actuator for changing the actual position. The TFCS is adapted to select a controller device configuration from a plurality of configurations dependent on an operating tape speed. The configurations are predetermined depending on a vibration frequency domain profile indicative of environmental vibrations induced to the head and tape to determine the control signal for adjusting an actuator output signal relative to a lateral tape motion signal. The TFCS is also adapted to feed-back a signal depending on a difference of the actuator output signal and the lateral tape motion signal to generate the PES.
    Type: Grant
    Filed: June 26, 2014
    Date of Patent: July 21, 2015
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Armando J Argumedo, Nhan X Bui, David H Harper, Randy C Inch, Kevin B Judd, Mark A Lantz, Angeliki Pantazi, Tomoko Taketomi
  • Publication number: 20150009590
    Abstract: Controlling the position of a head within a tape transport system. A track-follow control system (TFCS) includes a controller device for generating a control signal as a function of a position error signal (PES), wherein the PES indicates a difference between the actual and target positions of the head relative to the tape, and an actuator for changing the actual position. The TFCS is adapted to select a controller device configuration from a plurality of configurations dependent on an operating tape speed. The configurations are predetermined depending on a vibration frequency domain profile indicative of environmental vibrations induced to the head and tape to determine the control signal for adjusting an actuator output signal relative to a lateral tape motion signal. The TFCS is also adapted to feed-back a signal depending on a difference of the actuator output signal and the lateral tape motion signal to generate the PES.
    Type: Application
    Filed: June 26, 2014
    Publication date: January 8, 2015
    Inventors: Armando J. Argumedo, Nhan X. Bui, David H. Harper, Randy C. Inch, Kevin B. Judd, Mark A. Lantz, Angeliki Pantazi, Tomoko Taketomi
  • 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: 20140002916
    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: Application
    Filed: July 2, 2012
    Publication date: January 2, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventor: David H. Harper
  • Patent number: 8270108
    Abstract: A method, system and computer-usable medium are disclosed for performing data write and data read operations on a tape storage medium. A dual head/tape actuator assembly, comprising two head/tape actuator assemblies, is implemented to perform data write and data read operations on a tape medium. Each of the head/tape actuator assemblies comprises a set of data writer elements and a set of data reader elements. During data write operations, the data writer elements on one head/tape actuator assembly are used to write data to a tape medium and the data reader elements on the other head/tape actuator assembly are used to read the data from the tape medium. During read operations, half of the data readers on one head/tape actuator assembly are used to read data from half of the written data tracks on the tape medium and half of the data readers on the other head/tape actuator assembly are used to read the other half of the written tracks.
    Type: Grant
    Filed: August 28, 2009
    Date of Patent: September 18, 2012
    Assignee: International Business Machines Corporation
    Inventors: David H. Harper, Robert A. Hutchins, Peter V. Koeppe, Johnny L. Teale
  • Publication number: 20110051283
    Abstract: A method, system and computer-usable medium are disclosed for performing data write and data read operations on a tape storage medium. A dual head/tape actuator assembly, comprising two head/tape actuator assemblies, is implemented to perform data write and data read operations on a tape medium. Each of the head/tape actuator assemblies comprises a set of data writer elements and a set of data reader elements. During data write operations, the data writer elements on one head/tape actuator assembly are used to write data to a tape medium and the data reader elements on the other head/tape actuator assembly are used to read the data from the tape medium. During read operations, half of the data readers on one head/tape actuator assembly are used to read data from half of the written data tracks on the tape medium and half of the data readers on the other head/tape actuator assembly are used to read the other half of the written tracks.
    Type: Application
    Filed: August 28, 2009
    Publication date: March 3, 2011
    Inventors: David H. Harper, Robert A. Hutchins, Peter V. Koeppe, Johnny L. Teale
  • Patent number: 7092196
    Abstract: A system and method for analyzing a coil actuator of a type having a coil and a magnet. A current source selectively applies a first current to a coil of a coil actuator for setting a moveable part of the coil actuator to a first position. A recording system captures data corresponding to a back electromotive force voltage produced by oscillation of the coil actuator upon movement of the moveable part of the coil actuator to a second position. A processor applies a curve fit to the back electromotive force data for calculating a frequency characteristic and damping response of the coil actuator.
    Type: Grant
    Filed: June 23, 2004
    Date of Patent: August 15, 2006
    Assignee: International Business Machines Corporation
    Inventors: James H. Eaton, Darrell G. Follett, David H. Harper, Wayne I. Imaino, Leif S. Kirschenbaum, Andrew J. McKee, Luis H. Palacios
  • Patent number: 6934108
    Abstract: A system and method of controlling tape tension during operation of a tape drive by making use of pre-existing timing based servo patterns formatted on the media. Changes in servo pattern timing are read at regular intervals and used to calculate changes in tension, with the torque of the tape reel motors being adjusted accordingly.
    Type: Grant
    Filed: January 22, 2003
    Date of Patent: August 23, 2005
    Assignee: International Business Machines Corporation
    Inventors: David H. Harper, Mark A. Taylor
  • Publication number: 20040141250
    Abstract: A system and method of controlling tape tension during operation of a tape drive by making use of pre-existing timing based servo patterns formatted on the media. Changes in servo pattern timing are read at regular intervals and used to calculate changes in tension, with the torque of the tape reel motors being adjusted accordingly.
    Type: Application
    Filed: January 22, 2003
    Publication date: July 22, 2004
    Applicant: International Business Machines Corporation
    Inventors: David H. Harper, Mark A. Taylor
  • Patent number: 4025943
    Abstract: A silicon photoelement imager which includes a photogeneration channel consisting of a layer of doped semiconductor material, located on a support substrate having a layer of oppositely doped semiconductor material. The photogeneration channel, in which carriers are photogenerated, has an optimum effective thickness of d/.pi., where d is the center to center spacing of the photoelements; while the support substrate is sufficiently thick to provide strength and rigidity to the device. The support substrate layer is further biased with respect to the photogeneration channel so as to drain and prevent any carriers produced in the support substrate from entering the photogeneration channel. This photogeneration channel substrate structure can be used to improve the spatial resolution of CCD and MOSFET imagers.
    Type: Grant
    Filed: March 22, 1976
    Date of Patent: May 24, 1977
    Assignee: Canadian Patents and Development Limited
    Inventors: Savvas G. Chamberlain, David H. Harper