Applying an adaptive feed-forward algorithm as a frequency selective filter in a closed loop disk drive servo system in order to compensate for periodic perturbations which otherwise appear in the servo system position error signal
US5550685A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 22, 1993 |
| Grant date | Aug 27, 1996 |
| Priority date | — |
| Expiry date | Oct 22, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/59627
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method for applying an adaptive feed-forward waveform correction to a primary servo loop compensation signal in a rotating data storage apparatus. A position error signal is used to determine a fixed feed-forward correction upon initialization or other predetermined conditions. An adaptive feed-forward waveform correction is periodically determined by adding a scaled version of the position error signal to the stored adaptive feed-forward value, and then processing the resulting sum through a frequency selective filter. The stored adaptive feed-forward correction is then updated with this new result. Simultaneously, the updated adaptive feed-forward correction is combined with the fixed feed-forward correction and the position error signal to generate a primary servo loop compensation signal for controlling the read/write head of the data storage apparatus.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.