Radial self-propagation pattern generation for disk file servowriting
AssigneeInternational Business Machines Corporation
InventorsEdward John Yarmchuk, Mark Delorman Schultz, Bucknell C. Webb, Timothy Joseph Chainer
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Abstract
During a write revolution of a storage medium, a transition is written on the 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 the 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 in order to correct for the position error
Claims20
A method for determining the desired track pitch of tracks to be written on a storage medium of a storage device having a transducer, said method comprising:
- choosing an initial nominal average reference value;
- writing a transition on each of a plurality of said tracks, said plurality of tracks being less than a total number of said tracks, wherein spacing of said plurality of tracks is determined by said initial nominal average reference value;
- measuring a first relative amplitude of the transition written on one track of said plurality tracks and a second relative amplitude of the transition written on another track of said plurality of tracks;
- comparing said first relative amplitude and said second relative amplitude;
- positioning said transducer based on said comparing;
- repeating said measuring, comparing and positioning until said comparing indicates said first relative amplitude is substantially equal to said second relative amplitude, wherein a measured relative amplitude is obtained;
- comparing said measured relative amplitude to a predetermined value to obtain a deviation from said predetermined value;
- and
- determining a second nominal average reference value using said deviation, said second nominal average reference value being used to write subsequent tracks at said desired track pitch.
An apparatus for determining the desired track pitch of tracks to be written on a storage medium of a storage device having a transducer, said apparatus comprising:
- means for choosing an initial nominal average reference value;
- a pattern generator adapted to write a transition on each of a plurality of said tracks, said plurality of tracks being less than a total number of said tracks, wherein spacing of said plurality of tracks is determined by said initial nominal average reference value;
- means for measuring a first relative amplitude of the transition written on one track of said plurality tracks and a second relative amplitude of the transition written on another track of said plurality of tracks;
- means for comparing said first relative amplitude and said second relative amplitude;
- means for positioning said transducer based on said comparing;
- means for repeating said measuring, comparing and positioning until said comparing indicates said first relative amplitude is substantially equal to said second relative amplitude;
- wherein a measured relative amplitude is obtained;
- means for comparing said measured relative amplitude to a predetermined value to obtain a deviation from said predetermined value;
- and
- means for determining a second nominal average reference value using said deviation, said second nominal average reference value being used to write subsequent tracks at said desired track pitch.
A pattern propagation method in a storage device, said storage device comprising a storage medium and a transducer for interacting with said storage medium, said method comprising:
- writing, during a write revolution of said storage medium, a transition on said storage medium while servoing on another transition previously recorded on said storage medium;
- determining, during said write revolution, a position error signal corresponding to a position error of said transducer relative to said another transition;
- and
- storing, during said write revolution, said position error signal providing a recorded position error signal used in computing a reference track value associated with said transition to correct for said position error.
A pattern propagation apparatus in a storage device, said storage device comprising a storage medium and a transducer for interacting with said storage medium, said apparatus comprising:
- a pattern generator adapted to write, during a write revolution of said storage medium, a transition on said storage medium while servoing on another transition previously recorded on said storage medium;
- means for determining, during said write revolution, a position error signal corresponding to a position error of said transducer relative to said another transition;
- and
- a memory adapted to store, during said write revolution, said position error signal providing a recorded position error signal used in computing a reference track value associated with said transition to correct for said position error.
Dependencies are inferred from the claim text.