公开(公告)号：DE3875439T2

公开(公告)日：1993-04-22

申请号：DE3875439

申请日：1988-08-09

Applicant: IBM

Inventor： EDEL STEPHEN F ,  PHAM VAN ICH

IPC: G05B21/02 ,  G11B21/08 ,  G11B21/10 ,  G11B5/55 ,  G11B5/56 ,  G11B5/54

Abstract: A disk file digital servo control system incorporates means for measuring the time between samples of read/write head position error signals (PES), and uses a value of that measured time as part of the computation of the digital control signal. The digital servo control system has a microprocessor which runs a control signal algorithm, a portion of which is a state estimator for estimating the position, velocity and acceleration of the head. The state estimator requires the use of estimator constants determined from physical parameters of the disk file, including the PES sampling time. By using the actual measured PES sampling time, rather than a constant value of nominal PES sampling time, the estimator constants can be modified to improve the accuracy of the computed control signal. This results in improved performance of the control system to move the head to the target track whenever there are variations in the nominal PES sampling time caused by variations in the disk file drive motor speed.

公开(公告)号：DE3875439D1

公开(公告)日：1992-11-26

申请号：DE3875439

申请日：1988-08-09

Applicant: IBM

Inventor： EDEL STEPHEN F ,  PHAM VAN ICH

IPC: G05B21/02 ,  G11B21/08 ,  G11B21/10 ,  G11B5/55 ,  G11B5/56 ,  G11B5/54

Abstract: A disk file digital servo control system incorporates means for measuring the time between samples of read/write head position error signals (PES), and uses a value of that measured time as part of the computation of the digital control signal. The digital servo control system has a microprocessor which runs a control signal algorithm, a portion of which is a state estimator for estimating the position, velocity and acceleration of the head. The state estimator requires the use of estimator constants determined from physical parameters of the disk file, including the PES sampling time. By using the actual measured PES sampling time, rather than a constant value of nominal PES sampling time, the estimator constants can be modified to improve the accuracy of the computed control signal. This results in improved performance of the control system to move the head to the target track whenever there are variations in the nominal PES sampling time caused by variations in the disk file drive motor speed.