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:
Dec. 10, 2002
Filed:
Jul. 21, 2000
John C. Morris, Minneapolis, MN (US);
Yi-Ping Hsin, Burnsville, MN (US);
Seagate Technology LLC, Scotts Valley, CA (US);
Abstract
The present invention incorporates an add-on adaptive feedforward controller into the existent track-following servomechanism of a dual-actuator disc drive to suppress the disturbance caused by mechanical interaction of the two actuator assemblies to thereby enhance the positioning accuracy at track following. The control signal fed into the power amplifier of one actuator is also used as the input signal of an adaptive controller in the other one. In an illustrative embodiment, the information is fed into an adaptive LMS filter. The output of the adaptive filter is then used as a feedforward signal to coordinate the head position with the desired track position. By matching the unknown disturbance dynamics with a filtered-x LMS (least mean square) adaptation algorithm, the output of the feedforward controller is able to cancel the disturbance from mechanical interaction, and thereby realizes the necessary fast, accurate head positioning.