Patent · US Expired

Digital tracking servo system with multi-track seek

US6781929B2 · kind B2 · utility

12Cited by
57References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 10, 2001
Grant dateAug 24, 2004
Priority date
Expiry dateDec 26, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B7/08576
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A servo system with a multi-track seek algorithm is presented. The multi-track seek algorithm detects zero crossings in a tracking error signal, counts the number of zero crossings to form a count, and calculates a reference velocity from the count. The algorithm also determines a time period between successive zero crossings, calculates a velocity from the time period, calculates a difference signal between the reference velocity and the velocity, and adjusts the control signal so that the velocity follows the reference velocity. The reference velocity can follow a velocity profile with acceleration portions, coasting portions, and deceleration portions which move an optical pick-up unit from a starting position to a target position.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.