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. 13, 2003
Filed:
Dec. 29, 1999
Qiang Bi, Singapore, SG;
Kevin A. Gomez, Singapore, SG;
YangQuan Chen, Singapore, SG;
KianKeong Ooi, Singapore, SG;
Seagate Technology LLC, Scotts Valley, CA (US);
Abstract
A disc storage system is provided which includes a servo control loop for compensating for repeatable runout. Repeatable runout is compensated using table entries of the form Comp Value(k+1)=Comp Value(k)+K&PHgr;(z)RRO(k), where K is a learning rate; k is iteration number &PHgr;(z) is a filter and RRO(k) is the repeatable runout error. Further, &rgr;(j&ohgr;)=|1−K&PHgr;(j&ohgr;)/(1+PC(j&ohgr;)|<1 needs to be satisfied, where PC(j&ohgr;) is an open loop frequency response of the servo loop. The filter can comprise a order filter.