公开(公告)号：SG60131A1

公开(公告)日：1999-02-22

申请号：SG1997003800

申请日：1997-10-20

Applicant: IBM

Inventor： ABRAHAM DAVID WILLIAM ,  CHAINER TIMOTHY JOSEPH ,  ETZOLD KARL-FRIEDRICH ,  SCHRECK ERHARD THEORDOR

IPC: G01B21/08 ,  G01K15/00 ,  G01N25/72 ,  G11B5/00 ,  G11B5/012 ,  G11B5/455 ,  G11B5/48 ,  G11B5/58 ,  G01N25/70

Abstract: Apparatus and methods for calibrating a thermal proximity sensor are disclosed. Thermal responses from a thermal proximity sensor are used to sense the instantaneous distance between the sensor and a medium over which the sensor is moved, in a data storage system. Sensing the instantaneous distance results in detection of topographical variations on the medium. Calibration techniques for the sensor are disclosed herein and involve, in one aspect, using primarily electrical measurements to calibrate the sensor; and in another aspect, varying the distance between the sensor and the medium, obtaining actual thermal responses from the sensor, and using the actual responses (via direct comparison or curve fitting) to calibrate the sensor. In one embodiment, the sensor is a magnetoresistive access element used to access data on the medium.

公开(公告)号：DE19960769B4

公开(公告)日：2007-11-15

申请号：DE19960769

申请日：1999-12-16

Applicant: IBM

Inventor： CHAINER TIMOTHY JOSEPH ,  GREENGARD CLAUDE A ,  MOSKOWITZ PAUL ANDREW

IPC: G06K19/07 ,  G07C11/00 ,  G01S13/74 ,  G01S17/88 ,  G06K17/00 ,  G06Q40/08 ,  G06T9/00 ,  G09C1/00 ,  H04N1/00 ,  H04N1/32 ,  H04N1/387 ,  H04N5/765 ,  H04N5/781

Abstract: A system and method for authenticating an image of an object, include at least one identifier associated with the object, a receiver for interrogating the at least one identifier to produce identification information, a camera system for recording an image from the object including the at least one identifier, and a composite generator for encoding the identification information from the receiver along with the image acquired by the camera system, to produce composite data.

公开(公告)号：DE69525552T2

公开(公告)日：2002-10-10

申请号：DE69525552

申请日：1995-03-13

Applicant: IBM

Inventor： CHAINER TIMOTHY JOSEPH ,  SOHN WAYNE JAY ,  YARMCHUCK E J

IPC: G11B5/596

公开(公告)号：CA2365155C

公开(公告)日：2002-08-20

申请号：CA2365155

申请日：1995-11-24

Applicant: IBM

Inventor： SCHULTZ MARK DELORMAN ,  CHAINER TIMOTHY JOSEPH ,  YARMCHUK EDWARD JOHN ,  WEBB BUCKNELL C

IPC: G11B5/012 ,  G11B5/55 ,  G11B5/596 ,  G11B21/10

Abstract: A mechanism for servowriting on a storage medium of a storage device. The storage device has a transducer and a servo loop for positioning the transducer with respec t to the storage medium. At least one transition is written on a track of the storage medium, while servoing on other transitions previously recorded on the storage medium. A reference waveform is derived as a function of a closed loop response of the servo loop and a position error waveform. The position error waveform corresponds to one or more position errors of the transducer relative to the previously recorded transitions. The reference waveform is usable in writing subsequent tracks on the storage medium. Using the reference waveform for writing subsequent trac ks provides a substantial rejection of mechanical disturbances by the servo loop.

公开(公告)号：CA2366415C

公开(公告)日：2002-07-16

申请号：CA2366415

申请日：1995-11-24

Applicant: IBM

Inventor： YARMCHUK EDWARD JOHN ,  WEBB BUCKNELL C ,  SCHULTZ MARK DELORMAN ,  CHAINER TIMOTHY JOSEPH

IPC: G11B5/012 ,  G11B5/55 ,  G11B5/596 ,  G11B21/10

Abstract: During a write revolution of a storage medium, a transition is written on th e storage medium while servoing on another transition previously recorded on the storage medium. During that write revolution, a position error signal corresponding to the position error of t he transducer relative to the previously recorded transition is determined. That position error signal is then stored, during the write revolution, to be used in computing a reference track value associated with the transition being written to correct for the position error. Additionally, a product servo- pattern is written, which includes an embodying of the position error therein.

公开(公告)号：CA2365103C

公开(公告)日：2002-07-16

申请号：CA2365103

申请日：1995-11-24

Applicant: IBM

Inventor： WEBB BUCKNELL C ,  CHAINER TIMOTHY JOSEPH ,  YARMCHUK EDWARD JOHN ,  SCHULTZ MARK DELORMAN

IPC: G11B5/012 ,  G11B5/55 ,  G11B5/596 ,  G11B21/10

Abstract: During a write revolution of a storage medium, a transition is written on th e storage medium while servoing on another transition previously recorded on the storage medium. During that write revolution, a position error signal corresponding to the position error of t he transducer relative to the previously recorded transition is determined. That position error signal is then stored, during the write revolution, to be used in computing a reference track value associated with the transition being written to correct for the position error. Additionally, a product servo- pattern is written, which includes an embodying of the position error therein.

公开(公告)号：SG64425A1

公开(公告)日：1999-04-27

申请号：SG1997002067

申请日：1997-06-16

Applicant: IBM

Inventor： CHAINER TIMOTHY JOSEPH ,  SCHUTLZ MARK DELORMAN ,  WEBB BUCKNELL CHAPMAN ,  YARMCHUK EDWARD JOHN

IPC: G11B5/55 ,  G11B5/596 ,  G11B21/08 ,  G11B20/12

Abstract: A self-servowriting system and method for implementation in a storage device such as a disk drive are described. Two problems associated with self-propagation are greater mechanical disturbances and the growth of errors during many thousands of servowriting steps. Error growth is attributable to the special properties of servo loops as applied to a repetitive self-propagation process. Greater resistance to mechanical disturbances and reduction in error growth are achieved, in part, by adjusting a step amplification factor, S, at the initiation of servowriting to within desired parameters. However, S is known to vary with movement of the head in a direction transverse to the direction of the tracks. This problem is addressed by the present invention, wherein S is determined at a plurality of transverse transducer positions. S is dependent upon the closed loop response of the servo system C and upon a set of step-to-step correction factors f. S is therefore determined by monitoring an indicium of S such as C, and is adjusted by adjusting either C or f to provide a value of S which falls within an acceptable range of values. Determination of S is scheduled to occur at predefined intervals. The intervals may be fixed or adjusted adaptively based upon the measured variation of S with transducer position.

公开(公告)号：HUT77922A

公开(公告)日：1998-10-28

申请号：HU9801391

申请日：1995-03-13

Applicant: IBM

Inventor： CHAINER TIMOTHY JOSEPH ,  SOHN WAYNE JAY ,  YARMCHUK EDWARD JOHN

IPC: G11B5/596

Abstract: The method comprises the steps of generating a timing pattern on the storage medium with a recording head internal to the recording device, and determining a radial positioning value for at least one of radial regions from a pattern propagated by the internal recording head in the region. - The radial positioning value is used for positioning the internal recording head. A servo-pattern is recorded on the storage medium by the head, at locations determined by the timing pattern and the radial positioning value. - (Dwg.1a/18)

公开(公告)号：SG52937A1

公开(公告)日：1998-09-28

申请号：SG1997000894

申请日：1997-03-22

Applicant: IBM

Inventor： CHAINER TIMOTHY JOSEPH ,  SCHULTZ MARK DELORMAN ,  WEBB BUCKNELL CHAPMAN ,  YARMCHUK EDWARD JOHN

IPC: G11B5/48 ,  G11B5/55 ,  G11B5/596 ,  G11B21/08 ,  G11B21/10 ,  G11B27/30 ,  G11B5/58

Abstract: Methods and systems for self-servowriting a data storage medium are disclosed, including servoing to propagation bursts of a propagation pattern located in tracks other than an immediately preceding track. Reference levels used to position a recording head are accordingly kept in a usable dynamic range necessary to keep servo track spacing constant across the medium. The methods and systems are disclosed in connection with a rotary actuator having spaced read and write heads. Similar methods are disclosed for writing trigger or timing bursts of the propagation pattern.

公开(公告)号：SG50848A1

公开(公告)日：1998-07-20

申请号：SG1997002060

申请日：1997-06-14

Applicant: IBM

Inventor： CHAINER TIMOTHY JOSEPH ,  SCHULTZ MARK DELORMAN ,  WEBB BUCKNELL CHAPMAN ,  YARMCHUK EDWARD JOHN

IPC: G11B5/09 ,  G11B5/55 ,  G11B5/58 ,  G11B5/584 ,  G11B5/596 ,  G11B21/08 ,  G11B21/10 ,  G11B20/12

Abstract: An accurate and time-efficient method and system for self-servowriting wherein at least one reference value used to position the transducer is updated for some, but not all, of the tracks to be written. The reference value(s) is dependent upon a predefined indicium of transducer position, such as the amplitude of the readback signal obtained from a written track when the transducer is positioned on the track. In a first embodiment, updating of the reference value(s) is performed at every Nth track written, where N is a fixed number or range of numbers determined by an expected track-to-track variation of the indicium. The servowriting system may be designed to dynamically increase or decrease N during servowriting in response to actual variations in the indicium. According to a second embodiment, updating is only performed when needed, e.g. when the variation of the measured indicium between two written tracks (not necessarily adjacent tracks) exceeds a predefined threshold value. For systems employing dual-element heads, servowriting accuracy is enhanced by performing a read head adjustment prior to updating of the reference values.