System for head positioning control in a disk drive
US6417983B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 3, 1999 |
| Grant date | Jul 9, 2002 |
| Priority date | — |
| Expiry date | Sep 3, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/5556
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A system for positioning a head in a target position on a disk in a disk drive is realized by combining a feedback control system and a feed forward control system that is a learning system. The feed forward control system observes the position error computationally determined by the feedback control system and detects a track eccentric factor synchronized with the revolution of the disk from the outcome of the observation. The feed forward control system generates an oscillation with a predetermined frequency (sine wave) different from the period of revolution of the disk and adds it to the position error from the feedback control system. The feed forward control system then computationally determines a control value (Uf) for removing the synchronous factor (track eccentric factor) correlated among a plurality of tracks from the position error.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.