Disk file digital servo control system with compensation for variation in actuator acceleration factor
US4835633A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 16, 1987 |
| Grant date | May 30, 1989 |
| Priority date | — |
| Expiry date | Sep 16, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B21/085
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A data recording disk file with a voice coil motor (VCM) actuator and a digital servo control system for positioning the read/write heads to selected concentric data tracks includes means for calculating the factor relating acceleration of the heads to VCM input current. This permits each disk file to compensate for any variation in the nominal VCM physical parameters, thus enabling VCMs to be manufactured to less demanding tolerances. The disk file also calculates a unique acceleration factor for each head position during movement of the heads from one track to another, thereby improving the arrival time of the heads to the target track. During an initialization procedure, the disk file performs a track seek, during which VCM current and head velocity information are acquired and used by the microprocessor in the digital servo control system to calculate a value representing an average actual acceleration factor unique to that disk file. This value, together with predetermined constants representing the characteristic relationship of acceleration factor to head position in a disk file with a nominal VCM, are used by the microprocessor to calculate the actual acceleration factor fo…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.