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).
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Patent number: 9424869Abstract: 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: GrantFiled: July 17, 2015Date of Patent: August 23, 2016Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATIONInventors: Armando J. Argumedo, Nhan X. Bui, David H. Harper, Randy C. Inch, Kevin B. Judd, Mark A. Lantz, Angeliki Pantazi, Tomoko Taketomi
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Publication number: 20150325262Abstract: 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: ApplicationFiled: July 17, 2015Publication date: November 12, 2015Inventors: ARMANDO J. ARGUMEDO, NHAN X. BUI, DAVID H. HARPER, RANDY C. INCH, KEVIN B. JUDD, MARK A. LANTZ, ANGELIKl PANTAZI, TOMOKO TAKETOMI
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Patent number: 9087539Abstract: 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: GrantFiled: June 26, 2014Date of Patent: July 21, 2015Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATIONInventors: Armando J Argumedo, Nhan X Bui, David H Harper, Randy C Inch, Kevin B Judd, Mark A Lantz, Angeliki Pantazi, Tomoko Taketomi
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Publication number: 20150009590Abstract: 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: ApplicationFiled: June 26, 2014Publication date: January 8, 2015Inventors: Armando J. Argumedo, Nhan X. Bui, David H. Harper, Randy C. Inch, Kevin B. Judd, Mark A. Lantz, Angeliki Pantazi, Tomoko Taketomi
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Patent number: 8638523Abstract: 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: GrantFiled: July 2, 2012Date of Patent: January 28, 2014Assignee: International Business Machines CorporationInventor: David H. Harper
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Publication number: 20140002916Abstract: 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: ApplicationFiled: July 2, 2012Publication date: January 2, 2014Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATIONInventor: David H. Harper
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Patent number: 8270108Abstract: 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: GrantFiled: August 28, 2009Date of Patent: September 18, 2012Assignee: International Business Machines CorporationInventors: David H. Harper, Robert A. Hutchins, Peter V. Koeppe, Johnny L. Teale
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Publication number: 20110051283Abstract: 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: ApplicationFiled: August 28, 2009Publication date: March 3, 2011Inventors: David H. Harper, Robert A. Hutchins, Peter V. Koeppe, Johnny L. Teale
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Patent number: 7092196Abstract: 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: GrantFiled: June 23, 2004Date of Patent: August 15, 2006Assignee: International Business Machines CorporationInventors: James H. Eaton, Darrell G. Follett, David H. Harper, Wayne I. Imaino, Leif S. Kirschenbaum, Andrew J. McKee, Luis H. Palacios
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Patent number: 6934108Abstract: 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: GrantFiled: January 22, 2003Date of Patent: August 23, 2005Assignee: International Business Machines CorporationInventors: David H. Harper, Mark A. Taylor
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Publication number: 20040141250Abstract: 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: ApplicationFiled: January 22, 2003Publication date: July 22, 2004Applicant: International Business Machines CorporationInventors: David H. Harper, Mark A. Taylor
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Patent number: 4025943Abstract: 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: GrantFiled: March 22, 1976Date of Patent: May 24, 1977Assignee: Canadian Patents and Development LimitedInventors: Savvas G. Chamberlain, David H. Harper