Distributing tape drive abrasion

Patent metadata

Field	Value
Publication number	US-10062399-B1
Application number	US-201715856248-A
Country	US
Kind code	B1
Filing date	Dec 28, 2017
Priority date	Dec 28, 2017
Publication date	Aug 28, 2018
Grant date	Aug 28, 2018

Abstract

Some embodiments are directed to tape drive systems that oscillate the relative transverse position of the tape and magnetic head during seek operations (for example, by moving the head in the transverse direction). Some embodiments are directed to tape drive systems that select relative transverse position of the tape and magnetic head to counter uneven wear (for example, observed uneven wear, uneven wear predicted based on historical tape and drive usage data).

First claim

What is claimed is:

1. A tape drive system for use with a tape medium that defines a longitudinal direction and a transverse direction, the tape drive system comprising:
a magnetic head including a tape facing surface;
a head movement control sub-system;
a tape movement control sub-system; and
a head profile sub-system;
wherein:
the magnetic head is structured, connected, located, sized and shaped to magnetically read data from and/or magnetically write data to the tape medium while the tape medium moves in the longitudinal direction relative to the tape facing surface of the magnetic head;
the tape movement control sub-system structured and/or programmed to control movement of the tape medium, with the movement including longitudinal direction movement relative to the tape facing surface of the magnetic head;
the head profile sub-system is structured and/or programmed to store head profile information corresponding to an observed and/or estimated wear profile of the tape facing surface of the magnetic head; and
the head movement control sub-system and tape movement control sub-system are structured and/or programmed to control relative position and/or relative orientation of the tape facing surface of the magnetic head and a portion of the tape medium proximate to the magnetic head in a manner to counter uneven wear indicated by the wear profile information.

2. The system of claim 1 wherein the head movement control sub-system is further structured and/or programmed to move the magnetic head in the transverse direction to control relative transverse position of the tape facing surface of the magnetic head and a portion of the tape medium proximate to the magnetic head in a manner to counter uneven wear indicated by the wear profile information.

3. The system of claim 2 wherein the head movement control sub-system is further structured and/or programmed to move the magnetic head in the transverse direction to control relative transverse position of the tape facing surface of the magnetic head and a portion of the tape medium proximate to the magnetic head in a manner to counter uneven wear indicated by the wear profile information during fast forward type and rewind type operations performed by the tape drive system.

4. The system of claim 1 wherein the head profile sub-system is further structured and/or programmed to estimate the head profile information based upon historical data relating to usage and relative position of the magnetic head.

5. A method for use with an elongated magnetic tape medium defining a longitudinal direction and a transverse direction and a tape drive system including a magnetic head and a movement control sub-system, the method comprising:
controlling, by the movement control sub-system, the magnetic tape to move in the longitudinal direction relative to the magnetic head such that various portions of the magnetic tape will come into close proximity to a tape facing surface of the magnetic head and the magnetic tape moves in the longitudinal direction; and
while the magnetic tape is moving in the longitudinal direction, controlling, by the movement sub-system, the magnetic head to oscillate in the transverse direction.

6. The method of claim 5 further comprising:
receiving, by the tape drive, a locate command including information indicative of a target longitudinal location on the tape medium;
determining a locate time based upon a current longitudinal position of the tape medium, the target longitudinal location and a longitudinal speed of the tape medium in locate mode;
calculating, by the movement control sub-system, a stopping time based upon the locate time; and
stopping, by the movement control sub-system, the oscillation of the magnetic head at the stopping time.

7. The method of claim 6 wherein the calculation of the stopping time calculates the stopping time to be when ninety percent of the locate time has elapsed.

8. The method of claim 6 wherein the oscillation has a constant amplitude in the transverse direction.

9. The method of claim 6 wherein the oscillation has a constant period.

10. The method of claim 6 wherein a combined longitudinal and transverse motion pattern of the magnetic head with respect to the magnetic tape is sinusoidal.

11. A tape drive system for use with a tape medium that defines a longitudinal direction and a transverse direction, the tape drive system comprising:
a magnetic head including a tape facing surface;
a head movement control sub-system; and
a tape movement control sub-system;
wherein:
the magnetic head is structured, connected, located, sized and shaped to magnetically read data from and/or magnetically write data to the tape medium while the tape medium moves in the longitudinal direction relative to the tape facing surface of the magnetic head;
the tape movement control sub-system structured and/or programmed to control movement of the tape medium, with the movement including longitudinal direction movement relative to the tape facing surface of the magnetic head; and
the head movement control sub-system and tape movement control sub-system are structured and/or programmed to effect oscillatory movement during fast forward type and rewind type operations with respect to the relative transverse position of the tape facing surface of the magnetic head and a portion of the tape medium proximate to the magnetic head.

12. The system of claim 11 wherein:
the tape movement control sub-system is further structured and/or programmed to hold a portion of the tape medium proximate to the tape facing surface of the magnetic head at a substantially constant transverse position during the oscillatory movement; and
the head movement control sub-system is further structured and/or programmed to actuate transverse direction oscillatory motion by the tape facing surface of the magnetic head the oscillatory movement.

13. The system of claim 11 wherein the oscillatory movement has an amplitude that is greater than the center-to-center transverse width of two data tracks.

14. The system of claim 11 wherein the oscillatory movement has a constant amplitude in the transverse direction.

15. The system of claim 11 wherein the oscillatory movement has a constant period.

16. The system of claim 11 wherein a combined longitudinal and transverse motion pattern of the magnetic head with respect to the tape medium is sinusoidal.

17. The system of claim 11 wherein the head movement control sub-system and tape movement control sub-system are structured and/or programmed to effect the oscillatory movement during a locate mode that occurs in response to a locate command.

Assignees

• IBM

Inventors

• Breuer Marcus
• Freitag Bernd
• Krick Frank
• Oswald Tim

Classifications

• G11B5/1871 Primary

  Shaping or contouring of the transducing or guiding surface · CPC title

• G11B5/40 Primary

  Protective measures on heads, e.g. against excessive temperature  (G11B5/31 takes precedence; protection against wear G11B5/255  {; protective structure of the head: see under structures, e.g. G11B5/3106}) · CPC title

• G11B5/52

  with simultaneous movement of head and record carrier, e.g. rotation of head (G11B5/588 takes precedence) · CPC title

• G11B5/3106

  where the integrated or assembled structure comprises means for conditioning against physical detrimental influence, e.g. wear, contamination (G11B5/3133 takes precedence) · CPC title