Abstract: Systems and methods for reducing problems and disadvantages associated with protecting data during cold excursions are provided. A method for preventing unreliable data operations at cold temperatures may include determining whether a first internal temperature of a hard disk drive (HDD) is below a threshold temperature. The method may also include initiating an artificial seek operation if the first internal temperature is below the threshold temperature.

Abstract: A method according to one embodiment includes setting a default friction value to a predetermined value, determining whether a primary velocity is valid, determining a velocity error, determining whether the velocity error is in a predetermined range, accumulating the velocity error when the velocity error is determined to be in the predetermined range, repeating, until a time period has elapsed, each of: the determining the velocity error, the determining whether the velocity error is in the predetermined range, and the accumulating the velocity error when the velocity error is determined to be in the predetermined range, and calculating a new friction value based on the accumulated velocity error.

Abstract: A method according to one embodiment includes selecting an initial radius value (Rfull) for an outgoing reel, where Rfull is the initial radius of a tape on the outgoing reel; unwinding the tape from the outgoing reel; computing a radius value of the tape on the outgoing reel during the unwinding; adjusting the computed radius with an offset calculated from a direct measurement of velocity from the tape position; and outputting the adjusted computed radius. A method according to another embodiment includes selecting an initial radius value (R0) for an incoming reel, where R0 is the initial radius of the incoming reel; winding the tape onto the incoming reel; computing a radius value of the tape on the incoming reel during the winding; adjusting the computed radius with an offset calculated from a direct measurement of velocity from the tape position; and outputting the adjusted computed radius.

Abstract: In one embodiment, a system includes a controller configured to: determine a reference velocity at various intervals, receive or determine a secondary velocity based at least in part on a parameter associated with a drive mechanism motor, determine a value representative of a difference between the reference velocity and secondary velocity, adjust a speed of the motor of the drive mechanism for minimizing the difference between the reference velocity and secondary velocity, receive/determine a primary velocity based on reading information encoded on a magnetic tape, at a switching point, make the reference velocity about equal to the primary velocity, after the switching point, determine the reference velocity at various intervals, after the switching point, determine a value representative of a difference between the reference velocity and primary velocity, and adjust the speed of the motor of the drive mechanism for minimizing the difference between the reference velocity and primary velocity.

Abstract: A HDD including a temperature sensor for sensing ambient temperature in the HDD, a spindle motor comprising a fluid dynamic bearing; and a controller configured for adjusting a rotational speed of the spindle motor based on the measured ambient temperature while a rigidity of the fluid dynamic bearing is maintained, and reducing power consumption of the HDD based on the adjusting the rotational speed of the spindle motor.

Abstract: According to one embodiment, an information processing apparatus includes: a main unit; a first disk device provided in the main unit; a second disk device provided in the main unit; an acceleration sensor provided in the main unit and detecting an acceleration; a setting module for setting whether to execute a disk protection processing for at least one of the first disk device and the second disk device or not; and a controller for executing the processing on the disk device for which the execution of the processing is set by the setting module, when an acceleration is detected by the acceleration sensor.

Abstract: A tape movement constraint for a tape drive system, comprises a tiltable tape roller bearing having a grooved surface adapted to contact and engage a surface of the tape as the roller barrel rotates, and an actuator adapted to pivot the roller bearing surface when the actuator is actuated, to control the lateral position of a tape. In operation, in one embodiment, a roller barrel of the tiltable roller bearing is biased in a first position on a pivot axis, using magnetic attraction between a movable magnet and a return path structure of magnetically permeable material. The roller barrel is pivoted on the pivot axis by conducting current through a fixed coil to generate a magnetic field which is conducted by the return path structure to interact with the magnetic field of the magnet. Other embodiments are described and claimed.

Abstract: Provided are a computer program product, system, and method for a magnetic disk drive. The disk drive has at least one disk platter having at least one recordable disk surface having an areal density of at least 200 gigabits per square inch. Either a diameter of the at least one disk platter is greater than 3.5 inches or the at least one disk platter rotates at less than 5400 RPMs. A read/write head reads and writes tracks of data with respect to the at least one disk surface. Modified tracks from write requests to write to the at least one disk surface on the at least one disk platter are cached in a non-volatile storage device for caching modified tracks. Modified tracks are cached in the non-volatile storage device to later destage to the at least one disk surface.

Abstract: An output is generated in response to an indication associated with movement of a moveable part in a storage device. The output is for reducing a noise component associated with the movement of the moveable part.

Abstract: A method of operation of a servo writing system includes: initializing a disk and a head positioned over the disk for writing a servo pattern on the disk; calculating a target velocity profile for writing the servo pattern on the disk; setting a movement profile for operating the disk, the head, or a combination thereof to the target velocity profile; determining a back electromotive force from operating the disk, the head, or a combination thereof according to the movement profile; calculating an actual profile of the movement of the disk, the head, or a combination thereof from the back electromotive force; and adjusting the movement profile by the actual profile to match the actual profile to the target velocity profile for writing the servo pattern on the disk.

Abstract: High performance is obtained without preventing achievement of a target read data rate. In a controller 16 of a tape drive, a command processing unit 41 receives a synchronization command, and a buffer management unit 42 passes data in a buffer to a channel input-output unit 43. Then, upon completion of writing the data to the tape, a backhitch determination unit 44 determines whether or not to execute backhitch. If it is determined that backhitch should be skipped, the speed determination unit 46 determines a tape speed that minimizes a sum of a time required to write data without backhitch within a range where a data amount of a monitor target is to be written in order to achieve a target read data rate, and a time required to write data with backhitch within the range. Then, an operation signal output unit 49 issues an instruction to change the tape speed to the determined tape speed after execution of backhitch.

Abstract: A tape drive capable of switching the transport speed of a tape medium among multilevel speeds calculates a data transfer rate from/to a host device, and selects an adjustment mode of the transport speed of the tape medium from a constant speed mode and a speed switch mode according to the calculated data transfer rate. The tape drive in the speed switch mode, pauses a data write or read operation to switch the transport speed of the tape medium while data is written at a first transport speed and when an available capacity of a buffer memory reaches a data volume to be received from the host device during switching of the transport speed and is read out at the first transport speed and when a data volume of a buffer memory reaches a data volume to be transmitted to the host device during switching of the transport speed.

Abstract: A token value is maintained based on an allowable number of low power transitions of a hard disk drive without adversely affecting reliability, compared to an actual number of low power transitions of said hard disk drive. The allowable number of low power transitions increases over the hard disk drive's lifetime. Before the hard disk drive performs a low power transition, the token is evaluated to determine if the hard disk drive is allowed to perform a low power transition. Low power transitions discussed include parking the head and spinning-down the hard disk drive.

Abstract: According to one embodiment, a method of detecting contact of a magnetic head with a magnetic disk by changing the dynamic flying height of the magnetic head in a magnetic disk drive is disclosed. The method can change control of a spindle motor configured to rotate the magnetic disk, from feedback control to open loop control. The method can detect a change in rotational speed of the magnetic disk during the open loop control. The method can detect contact of the magnetic head with the magnetic disk based on the detected change in the rotational speed.

Abstract: A hard disk drive includes a storage surface, a motor, a read/write had, and a number of regions into which the storage surface is divisible. Data is writable to and data is readable from the storage surface. The motor is to rotate the storage surface at a variable speed. The read/write head is to write data to and read data from the storage surface while the storage surface is rotated by the motor. Each region corresponds to a different speed at which the storage surface is rotated for the read/write head to write data to and read data from the region.

Abstract: An optical recording medium (disk) capable of preventing a back focus at a face thereof and reducing the interference between beams reflected by each recording surface, thereby improving a quality of a servo signal and a reproductive signal. In a disk having (N?1) layers, if N is a natural number (more than three), and if a cover-layer thickness and intermediate-layer thicknesses are d1, d2, . . . dN, then a difference of 1 ?m or above is set between the sum of di to dj and the sum of dk to dm for arbitrary natural numbers i, j, k, m (i?j?k?m?N). If refractive indexes are different from a standard value or different for each layer, then the thickness of each layer is converted based on a spread width of light according to the thickness.

Abstract: The present invention makes is possible to appropriately set the power saving control of the storage device from the management device of the storage device. In addition, the storage device executes control of the power saving for the magnetic disk device after ensuring consistency between an instruction from the administrator and the operating state of the magnetic disk device in the storage device.

Abstract: A tape drive capable of switching the transport speed of a tape medium among multilevel speeds calculates a data transfer rate from/to a host device, and selects an adjustment mode of the transport speed of the tape medium from a constant speed mode and a speed switch mode according to the calculated data transfer rate. The tape drive in the speed switch mode, pauses a data write or read operation to switch the transport speed of the tape medium while data is written at a first transport speed and when an available capacity of a buffer memory reaches a data volume to be received from the host device during switching of the transport speed and is read out at the first transport speed and when a data volume of a buffer memory reaches a data volume to be transmitted to the host device during switching of the transport speed.

Abstract: Various embodiments for writing received synchronized data to magnetic tape having a plurality of wraps using a magnetic tape drive adapted for performing the writing according to an available plurality of predefined tape speeds are provided. In one such embodiment, for each of the available plurality of predefined tape speeds, an average overhead per synchronized command for performing a recursively accumulated backhitchless flush (RABF) cycle is calculated. One of the available plurality of predefined tape speeds having a lowest calculated average overhead is selected. The RABF cycle is performed using the selected one of the available plurality of predefined tape speeds.

Abstract: In a particular embodiment, a system is disclosed that includes a solid-state data storage medium, a disc data storage medium, and a controller adapted to selectively adjust a spindle speed associated with the disc data storage medium and a buffer size associated with the solid-state data storage medium responsive to a trigger.

Abstract: A system and method for overcoming adhesion between media and a surface of a storage device in contact with the media. A storage device comprises a media velocity detector and a media drive motor controller. The media velocity detector detects storage media velocity as torque is applied to a storage media. The media drive motor controller causes a media drive motor to apply acceleration torque to the storage media. If the media velocity detector detects no increase in media velocity as acceleration torque is applied to the storage media, then the media drive motor controller causes the media drive motor to apply a torque pulse to the storage media.

Abstract: A magnetic recording and reproducing apparatus includes a magnetic head that has a spin-torque oscillator and a magnetic disk and the spin-torque oscillator detects a magnetic field from the magnetic disk and outputs a signal. A criterion used to determine the rotational speed of the magnetic disk, the frequency shift of the spin-torque oscillator produced by a magnetic field from the magnetic disk, a characteristic oscillation frequency of the spin-torque oscillator and the full-width at half maximum of an oscillation spectrum is given in order for a read signal output from the spin-torque oscillator to satisfy a desired signal-to-noise ratio and a magnetic recording and reproducing apparatus is configured based on the criterion.

Abstract: According to one embodiment, a disk drive is disclosed to which a plurality of disk rotational speed modes can be set. The disk drive is configured such that input of servo data from servo sectors is thinned out by thinning out an output of an interrupt request to a CPU in a high-speed rotation mode. At the time, a disk controller obtains servo data reproduced from all the servo sectors at timing of servo gates and stores it to a register.

Abstract: Techniques are provided herein for reducing vibrations in various modes of a dynamic system. One such technique comprises incorporating vibration limiting and sensitivity constraints into a partial fraction expansion equation model of the system so as to reduce vibrations to specific levels. Another technique comprises shaping a command determined using the partial fraction expansion equation model to produce a desired output. The entire command may be shaped or only selected portions thereof which produce vibrations. Another technique involves commanding in current to produce saturation in voltage. By doing this it is possible to command voltage switches. The times at which the switches occur can be set to reduce system vibrations. Other techniques are also provided. These include varying transient portions at the beginning, middle and/or end of a move and using Posicast inputs, among others.