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:
Aug. 28, 2012
Filed:
Mar. 21, 2011
Shan Tang, Irvine, CA (US);
Shan Tang, Irvine, CA (US);
Western Digital Technologies, Inc., Irvine, CA (US);
Abstract
A disk drive is disclosed comprising a disk surface, a head coupled to a distal end of an actuator arm, and a dual stage actuator (DSA) servo loop comprising a voice coil motor (VCM) servo loop and a microactuator servo loop operable to actuate the head over the disk surface. The microactuator servo loop is disabled, and after disabling the microactuator servo loop a sinusoid is injected into the VCM servo loop, wherein the sinusoid comprises a target frequency. A first open loop response of the VCM servo loop is computed. The microactuator servo loop is enabled, and after enabling the microactuator servo loop the sinusoid is injected into the DSA servo loop. A second open loop response of the DSA servo loop is computed. A microactuator servo loop gain and a VCM servo loop gain are tuned in response to the first and second open loop responses.