Head positioning servo-mechanism with error reduction capabilities

摘要

A velocity servo system for a disk drive, the servo system being responsive to digital signals and generating a control signal for moving a read head of the disk drive from a current track position to a commanded track position. The servo system includes a circuit for reading current track address information and servo bursts recorded on a disk in said disk drive and for generating threshold signals when said read servo bursts are of a predetermined amplitude. An appropriately programmed data processing system provides a decoder responsive to the current track address read by the reading means and to the threshold signals for generating a current half track address, a first comparator which compares the current half track address with the commanded track position to generate half tracks-to-go digital data in response thereto; and generates commanded acceleration data in response to the half tracks-to-go data and to successive half track addresses. The servo system further includes a digital to analog converter for converting said commanded acceleration data to said control signal.