Disc drive apparatus with tracking control based on multiple reference tracks and with automatic seek time adjustment

摘要

The present invention provides a disc drive apparatus having an improved tracking control and seek time adjustment. The head tracking error distribution along the disc radius is determined with reference to the phases of a plurality of position sensors and is calculated based on the tracking error of a reference track in first and second reference regions with respect to the signal from one of the position sensors. This information is used to determine the tracking error distribution along the disc radius with respect to that one of the position sensors. The tracking error distribution is used to determine the tracking error of a reference track in a third reference region with respect to the signal from the same position sensor. This tracking error is used to determine the tracking error of other reference tracks in the third reference region with respect to the signals from other of the position sensors. The tracking error of the reference tracks is then used to determine the tracking error of the data tracks on the disc. The present invention also provides a disc drive apparatus having an automatic seek time adjustment. A predetermined number of tracks is moved through based on a set head velocity. The seek time is compared to a prescribed seek time. If the two times differ, the velocity is adjusted until the prescribed seek time is achieved.