The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 01, 2007
Filed:
Oct. 14, 2005
Zhi Wang, San Jose, CA (US);
Jenghung Chen, Cupertino, CA (US);
Chun Sei Tsai, Tustin, CA (US);
Carl E. Barlow, Lake Forest, CA (US);
Zhi Wang, San Jose, CA (US);
Jenghung Chen, Cupertino, CA (US);
Chun Sei Tsai, Tustin, CA (US);
Carl E. Barlow, Lake Forest, CA (US);
Western Digital Technologies, Inc., Lake Forest, CA (US);
Abstract
Disclosed is a disk drive to characterize misaligned servo wedges. A disk of the disk drive includes a plurality of circumferential tracks, in which, each track includes a plurality of servo wedges spaced sequentially around the circumference of the track wherein the servo wedges may be misaligned relative to the head of the disk drive that moves about a pivot. A servo controller is used to characterize the misaligned servo wedges relative to the head during a seek operation by implementing the following operations: commanding the head to perform a seek operation from a starting track to an ending track; obtaining samples of wedge-to-wedge time (WTWT) values corresponding to time intervals between identified servo wedges for sampled tracks traversed during the seek operation; calculating WTWT variations for each sample; and calculating a calibrated misalignment value for each sample based upon WTWT variations.