-
公开(公告)号：JP2000173198A
公开(公告)日：2000-06-23
申请号：JP33615298
申请日：1998-11-26
Applicant: IBM
Inventor： KIMURA JUNICHI , HASHIMOTO SATOSHI , KISAKA MASASHI
Abstract: PROBLEM TO BE SOLVED: To easily detect the error caused by thermal asperity by controlling a recording and reproducing means and executing an error recovery processing without conducting a compensation by a compensating means when an error is detected in a recording and reproducing operation. SOLUTION: An arm electronic circuit (AE) 3 is provided with a signal adaptive filter 3a. The SAF 3a reduces the adverse effect caused by thermal asperity (TA) through eliminating the low frequency components of the reproduced output of a head 2, for example. Note that the operation of the SAF 3a is made controllable from an MPU 7, the SAF 3a is invalidated while executing an ERP, and TA is positively detected. By adding a step which invalidates the operation of the SAF3a that compensates for the reproduced output of the head 2 during an error recovery processing, thermal asperity is easily detected and the data sector, in which TA is generated, is surely registered as a defective sector.
-
公开(公告)号：JPH064102A
公开(公告)日：1994-01-14
申请号：JP13715792
申请日：1992-05-28
Applicant: IBM
Inventor： KISAKA MASASHI
Abstract: PURPOSE: To calculate a manipulated variable based on an obtained control deviation by a compensating means, and to output a control pulse having height and width corresponding to the manipulated variable to an object to be controlled by detecting a controlled variable by a detecting means in each prescribed timing, and comparing the controlled variable with a target value. CONSTITUTION: A target value is set by a setting part 1, and a controlled variable from an object 6 to be controlled is detected by a detecting part 2 in each prescribed timing. A control deviation is calculated by a comparator 3 based on the target value set by the setting part l and the controlled variable detected by the detecting part 2. A manipulated variable is generated by a compensating part 4 based on the control deviation from the comparator 3. The height H of a pulse is calculated by a controlling part 4 based on the manipulated variable from the compensating part 4, and a control pulse 10 with the calculated height H and a preliminarily decided width W is supplied to the object 6 to be controlled. Thus, adaptive control can be attained by always executing optimal control according to the variable parameter of a closed loop system in this digital closed loop system control system.
-
公开(公告)号：JPH03120676A
公开(公告)日：1991-05-22
申请号：JP25250889
申请日：1989-09-29
Applicant: IBM
Inventor： KISAKA MASASHI , MIZUNO TAKESHI
Abstract: PURPOSE: To attain the precise followup operation of a track by generating 1st-4th detecting signals by a detection means against respective 1st-4th servo patterns passing under the head and generating a value of coefficient K by a calculation means in which the 1st-4th detecting signals are received. CONSTITUTION: The 1st and 2nd servo patterns are recorded respectively on one side and another side of a line showing the respective centers of data tracks of a rotating disk, i.e., information storage tracks, and the 3rd and 4th servo patterns are respectively recorded on one side and another side of a line separated from the center line of the data tracks. By the detection means 32-35, the 1st-4th detecting signals A-D are generated against each of the 1st-4th servo patterns passing under the head 5, then the 1st-4th detecting signals A-D are received by the calculation means 41, 42, 46 and the value of coefficient K is generated. Thus, the precise followup operation is carried out.
-
-
Search Results
23
records
(took 0.019 seconds)
