Method and apparatus for transporting a recording medium with an adaptive velocity change profile
US4731679A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 20, 1984 |
| Grant date | Mar 15, 1988 |
| Priority date | — |
| Expiry date | Sep 20, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/90
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An adaptive velocity change profile for control of a video tape transport apparatus during a cue mode. The tape transport apparatus moves the video tape to a cue point in the shortest time available by adapting a deceleration velocity change profile to the actual ballistics of transport of the tape. When in a cue mode, the transport uses a commanded velocity signal generator to produce digital numbers which are applied as a reference speed signal to a velocity servo driving the takeup reel of the transport. For distances separating a selected frame location on the tape from the cue point greater than a predetermined distance, the commanded velocity is the maximum available from the transport. For distances to the cue point less than the predetermined distance, the commanded velocity is generated from an adaptive cue profile which decelerates the transport of the tape quickly as the selected frame location approaches the cue point without overshooting the mark. The deceleration velocity change profile is optimized as according to the distance separating the selected frame location from the cue point and the measured ballastics of transport of the tape. The measured ballistics of tra…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.