Patent classifications
G11B5/553
Reducing the effect of actuator cross-coupling in split actuator drives
Motion of a first actuator in a multi-actuator drive is prevented from affecting a second actuator in the drive or from being affected by the second actuator. A coupling coordinator generates a hold command for the second actuator based on an operation to be carried out using the first actuator, where the hold command is generated before commands to carry out the operation are issued. The hold command may cause an aggressor actuator in the drive to halt a disturbance-generating operation being performed by the aggressor actuator or delay initiation of such an operation that is to be performed by the aggressor actuator. The hold command may cause a victim actuator in the drive to pause the execution of a sensitive operation being performed by the victim actuator or delay initiation of such an operation that is to be performed by the victim actuator.
Split-actuator drive that coordinates timing of aggressor and victim for effective victim disturbance-feedforward
A victim feedforward signal is added to a microactuator control signal of the victim actuator in response to a voice-coil motor (VCM) control signal that is applied to the aggressor actuator, where the victim feedforward signal is configured to compensate for disturbances to a victim head caused by assertion of the aggressor VCM control signal. Each aggressor VCM control signal is asserted at a specific time by the aggressor actuator, for example in response to the aggressor head passing over a first servo wedge. A feedforward signal that compensates for the effect of the aggressor VCM control signal is then determined based on the aggressor VCM control signal, stored, and asserted via the victim microactuator at a predetermined time relative to when the aggressor VCM control signal is asserted.
Magnetic disk device and data protection method thereof
According to one embodiment, a monitoring unit of a magnetic disk device monitors a supply voltage supplied to a plurality of actuators by a first threshold value at which power supply by back electromotive force of a motor is started, and a second threshold value that is larger than the first threshold value. In a case where the supply voltage is lower than or equal to the second threshold value and is higher than the first threshold value, a controller interrupts execution of processing of reading/writing data to a magnetic disk in at least one of the actuators according to a predetermined condition based on execution status of the processing in the actuators.
Split-actuator drive that coordinates timing of aggressor and victim for effective victim disturbance-feedforward
A victim feedforward signal is added to a microactuator control signal of the victim actuator in response to a voice-coil motor (VCM) control signal that is applied to the aggressor actuator, where the victim feedforward signal is configured to compensate for disturbances to a victim head caused by assertion of the aggressor VCM control signal. Each aggressor VCM control signal is asserted at a specific time by the aggressor actuator, for example in response to the aggressor head passing over a first servo wedge. A feedforward signal that compensates for the effect of the aggressor VCM control signal is then determined based on the aggressor VCM control signal, stored, and asserted via the victim microactuator at a predetermined time relative to when the aggressor VCM control signal is asserted.
Tape recording system and method for reading media having write-append head-positioning based on change in tape lateral dimension
The present disclosure generally relates to a tape drive comprising a tape head comprising one or more modules, wherein each module comprises a plurality of servo readers; a plurality of read elements; and a control circuitry configured to retrieve a priority servo reader designation for a bundle of data tracks of the plurality of data tracks, wherein the priority servo reader designation is one or more servo readers of the plurality of servo readers; use the designated priority servo reader to adjust a lateral position the tape head; retrieve a target delta Y position (ΔYpos); and adjust a tilt of the tape head based on the target ΔYpos.
MAGNETIC DISK DEVICE AND METHOD
According to one embodiment, first setting information and second setting information are stored in a memory included in a magnetic disk device. The first setting information indicates a second track that is a first track set to be disused on the basis of a defect inspection among a plurality of first tracks included in a magnetic disk. The second setting information indicates a third track selected from one or more first tracks different from the second track. In a case where an access destination is a user area, the controller converts logical address information into physical address information while slipping the second track and the third track. In a case where an access destination is a system area, the controller converts logical address information into physical address information while slipping all of the first tracks other than the third track among the plurality of first tracks.
Tape Recording System And Method For Reading Media Having Write-Append Head-Positioning Based On Change In Tape Lateral Dimension
The present disclosure generally relates to a tape drive comprising a tape head comprising one or more modules, wherein each module comprises a plurality of servo readers; a plurality of read elements; and a control circuitry configured to retrieve a priority servo reader designation for a bundle of data tracks of the plurality of data tracks, wherein the priority servo reader designation is one or more servo readers of the plurality of servo readers; use the designated priority servo reader to adjust a lateral position the tape head; retrieve a target delta Y position (ΔYpos); and adjust a tilt of the tape head based on the target ΔYpos.
Magnetic tape, magnetic tape cartridge, and magnetic tape apparatus
The magnetic tape includes a non-magnetic support; and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support, in which the magnetic layer has a servo pattern, and an absolute value ΔN of a difference between a refractive index Nxy measured regarding an in-plane direction of the magnetic layer and a refractive index Nz measured regarding a thickness direction of the magnetic layer is 0.25 to 0.40, a magnetic tape cartridge and a magnetic tape apparatus including this magnetic tape.
Magnetic tape, magnetic tape cartridge, and magnetic tape apparatus
The magnetic tape includes a non-magnetic support; and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support, in which the magnetic layer has a servo pattern, and an absolute value ΔN of a difference between a refractive index Nxy measured regarding an in-plane direction of the magnetic layer and a refractive index Nz measured regarding a thickness direction of the magnetic layer is 0.25 to 0.40, a magnetic tape cartridge and a magnetic tape apparatus including this magnetic tape.
SPLIT-ACTUATOR DRIVE THAT COORDINATES TIMING OF AGGRESSOR AND VICTIM FOR EFFECTIVE VICTIM DISTURBANCE-FEEDFORWARD
A victim feedforward signal is added to a microactuator control signal of the victim actuator in response to a voice-coil motor (VCM) control signal that is applied to the aggressor actuator, where the victim feedforward signal is configured to compensate for disturbances to a victim head caused by assertion of the aggressor VCM control signal. Each aggressor VCM control signal is asserted at a specific time by the aggressor actuator, for example in response to the aggressor head passing over a first servo wedge. A feedforward signal that compensates for the effect of the aggressor VCM control signal is then determined based on the aggressor VCM control signal, stored, and asserted via the victim microactuator at a predetermined time relative to when the aggressor VCM control signal is asserted.