Multi-channel magnetic tape system having optical tracking servo
View Patent ↗A magnetic storage medium formed on a front major surface of a tape substrate defines a multiplicity of longitudinal data recording and playback tracks, each track having a nominal lateral location relative to the other tracks: and a predetermined optically manifested track servo pattern defined on the back major surface of the tape for indicating lateral displacement of the tape from a nominal lateral location of the track during tape movement across a read/write head. A magnetic tape recording and playback system employing the magnetic storage medium is also disclosed.
1. A tape drive system for use with a tape having a magnetic side and an optical side with optical servo tracks formed thereon, the tape drive system comprising:
a movable optical head which detects information relating to the optical servo tracks;
a movable magnetic head which reads and writes data on the magnetic side of the tape;
an assembly which couples movement of the magnetic head to movement of the optical head;
a motor which controls movement of the assembly;
an optical servo control system which controls movement of the assembly based on the information relating to the optical servo tracks detected by the optical head, wherein the optical servo control system includes a fine position servo loop, the fine position servo loop outputting a signal to control the motor based on the information relating to the optical servo tracks; and
a pivoting beam structure coupled between the motor and the assembly, the motor applying a torque force to the pivoting beam structure that causes movement of the assembly.
2. A tape drive system for use with a tape having a magnetic side and an optical side with optical servo tracks formed thereon, the tape drive system comprising:
a movable optical head which detects information relating to the optical servo tracks;
a movable magnetic head which reads and writes data on the magnetic side of the tape;
an assembly which couples movement of the magnetic head to movement of the optical head; and
an optical servo control system which controls movement of the assembly based on the information relating to the optical servo tracks detected by the optical head, wherein the optical servo control system comprises a coarse head position control system and a fine position servo control loop, the coarse head position control system causing the assembly to move in preset increments and the fine position servo control loop causing the optical head to follow an optical track formed on the tape.
3. The tape drive system of claim 2 , further comprising: a stepper motor, controlled by the coarse head position control system, which controls motion of the assembly.
4. A method, for use in a tape drive system comprised of a tape having a magnetic side and an optical side with optical servo tracks formed thereon, an optical head, a magnetic head, an assembly which couples movement of the magnetic head to movement of the optical head, and an optical servo control system, the method comprising:
detecting information relating to the optical servo tracks using the optical head;
controlling movement of the assembly, using the optical servo control system, based on the information relating to the optical servo tracks detected by the optical head and using a motor, wherein the optical servo control system comprises a fine position servo loop, the fine position servo loop outputting a signal to control the motor based on the information relating to the optical servo tracks; and
applying a torque force, using the motor, to a pivoting beam structure coupled between the motor and the assembly, the torque force causing movement of the assembly.
5. A method, for use in a tape drive system comprised of a tape having a magnetic side and an optical side with optical servo tracks formed thereon, an optical head, a magnetic head, an assembly which couples movement of the magnetic head to movement of the optical head, and an optical servo control system, the method comprising:
detecting information relating to the optical servo tracks using the optical head; and
controlling movement of the assembly, using the optical servo control system, based on the information relating to the optical servo tracks detected by the optical head, wherein the optical servo control system comprises a coarse head position control system and a fine position servo control loop, the coarse head position control system causing the assembly to move in preset increments and the fine position servo control loop causing the optical head to follow an optical track formed on the tape.
6. The method of claim 5 , further comprising: controlling motion of the assembly using a stepper motor that is controlled by the coarse head position control system.
7. The method of claim 6 , wherein the assembly comprises first and second arms, the magnetic head being coupled to the first arm and the optical head being coupled to the second arm such that the magnetic head faces in a direction of the optical head; and
further comprising moving the tape through a space between the magnetic head and the optical head such that the magnetic side faces the magnetic head and the optical side faces the optical head.
8. A tape drive system for use with a tape having a magnetic side and an optical side with optical servo tracks formed thereon, the tape drive system comprising: means for detecting information relating to the optical servo tracks; means for reading and writing data on the magnetic side of the tape; and means for coupling movement of the magnetic head to movement of the optical head during reading and writing.
9. The tape drive system of claim 8 , wherein the means for coupling comprises a first arm for holding the means for detecting and a second arm for holding the means for reading and writing, the first and second arms being connected physically.
10. The tape drive system of claim 8 , wherein the means for coupling comprises a U-shaped member onto which the means for detecting and the means for reading and writing are disposed, and through which the tape moves.
11. The tape drive system of claim 8 , further comprising: means for controlling movement of the assembly based on the information relating to the optical servo tracks detected by the means for detecting.
12. The tape drive system of claim 11 , wherein the information relating to the optical servo tracks comprises positional information that is used by the means for controlling to move at least one of the means for reading and writing and the means for detecting by controlling movement of the assembly.
13. A system comprising:
a tape having a magnetic side and an optical side having optical servo tracks;
a magneto-optic head system having a magnetic head and an optical head, the magneto-optic head system physically coupling the magnetic head to the optical head, wherein the magneto-optic head system comprises a first arm for holding the magnetic head and a second arm for holding the optical head, the first and second arms being connected physically;
an optical servo control system that aligns the magneto-optic head system to the tape, wherein the optical servo control system comprises a fine position servo loop, the fine position servo loop outputting a signal based on the information relating to the optical servo tracks to control the motor; and
a pivoting beam structure coupled between the motor and the magneto-optic head system, the motor applying a torque force to the pivoting beam structure that causes movement of the magneto-optic head system.
14. A system comprising:
a tape having a magnetic side and an optical side having optical servo tracks;
a magneto-optic head system having a magnetic head and an optical head, the magneto-optic head system physically coupling the magnetic head to the optical head; and
an optical servo control system that aligns the magneto-optic head system to the tape, wherein the optical servo control system comprises a coarse head position control system and a fine position servo control loop, the coarse head position control system causing the magneto-optic head system to move in preset increments and the fine position servo control loop causing the optical bead to follow an optical servo track formed on the tape.
15. The tape drive system of claim 14 , wherein the fine position servo control loop causes the optical head to move to a select optical servo track and to follow the select optical servo track and said system further comprising:
a stepper motor, controlled by the coarse head position control system, which controls motion of the magneto-optic head system.