Abstract: A disk drive is discloses comprising a disk, a head connected to a distal end of an actuator arm, and a voice coil motor (VCM) for rotating the actuator arm about a pivot in order to actuate the head radially over the disk. If when a power failure occurs the radial location of the head is less than a predetermined distance from the outer diameter of the disk, the VCM is controlled to move the head toward the inner diameter of the disk and stopping the head before it reaches the inner diameter of the disk. The VCM is then controlled to move the head toward the outer diameter of the disk until the actuator arm unloads onto a ramp.

Abstract: Methods in accordance with the present invention can include determining a position of a head along a stroke by locating one or more marker-zones printed to a reference surface of a disk. The one or more marker-zones can be printed to a portion of the reference surface as one or more pulses from a template pattern that can further comprise a plurality of chevrons. In one embodiment, each pulse can trace the motion of the stroke along at least a portion of the radius of the reference surface. A pulse can identify a marker-zone edge when the pulse disappears at some radius from the center of the disk. By moving the head along the stroke, the marker-zone edge can be detected and a gross position determined. A fractional position can be determined by measuring a phase of a chevron located at substantially the same radial location as the edge.

Abstract: A servo pattern is described that facilitates high resolution and wide dynamic range to accurately pinpoint servo track centerlines on a magnetic tape. The servo pattern provides both absolute positioning information over an entire servo band and absolute positioning information relative to the centerline of each servo track included in the servo band. Therefore, the servo pattern includes implicit servo track identification in a single servo band, eliminating the need for conventional track identification marks. In other words, the servo pattern, itself, can distinguish one servo track from another servo track in the single servo band as well as provide highly accurate positioning information relative to each of the servo track centerlines.

Abstract: A disk drive includes a slider assembly and a controller that directs current to the slider assembly to dynamically adjust the head-to-disk spacing. In one embodiment, the slider assembly includes a write element having a first end, a second end and an intermediate section, a conductor that is connected to the intermediate section. In this embodiment, the controller directs electrical current through the conductor to heat the write element without writing data to a storage disk. The electrical current can be directed through the conductor at any time prior to data transfer or during data transfer. Heating the write element causes a deformation of the slider assembly to decrease the head-to-disk spacing. In another embodiment, the slider assembly includes a separate slider deformer. Electrical current is selectively directed to the slider deformer to cause a deformation of the slider assembly to obtain a desired head-to-disk spacing.

Abstract: Briefly, descriptions of embodiments for, at least practically, reducing the power consumption of a mass storage device are provided. The present disclosure relates to at least partially reducing the power consumption of a mass storage device and, more particularly, to a method and device for at least partially reducing the power consumption of a mass storage device. One embodiment may include a power supply coupled with at least one mass storage device, and a control circuit. The control circuit may be capable of at least partially dynamically adjusting the amount of electrical power supplied to the mass storage device based, at least in part, upon at least one signal provided to the control circuit.

Abstract: A magnetic tape which is run at a speed of 4 m/sec. or higher and has recording tracks with a width of 21 ?m or less, and which includes a non-magnetic support, at least one magnetic layer formed on one surface of the non-magnetic support, and a backcoat layer formed on the other surface of the non-magnetic support, wherein servo signals for controlling tracking are recorded on the magnetic layer or the backcoat layer, the value of (?/W) X (V/f) is 10 [s?1] or less, and/or the value of (?/W) is 0.1 or less, wherein V [mm/sec.] is the tape-running speed; ? [?m] is an amount of a weave with a cycle of f [mm] on one edge of the tape or the other edge thereof, as the reference side, for the running of the tape; and W [?m] is a width of the recording track. The magnetic tape can decrease PES and off-track and thus is excellent in servo tracking performance.

Abstract: A rotating media storage device (RMSD) to adaptively estimate a read access time to a second track based on the radial position of the second track is disclosed. The RMSD includes a disk having at least a first track and a second track and a microprocessor for controlling operations in the RMSD including seek operations. During a seek operation, the microprocessor bins a radial position of the second track and estimates a read access time to the second track based on the binned radial position of the second track.

Abstract: A method and apparatus for reducing tape media edge damage in data regions. The present invention controls where popped strand occur by shifting the wrap turn around/stream points in the tape media to an unused region of tape. As data is written for the length of the tape, when a wrap turn around point is reached, the write current is shut off. However, the servo motors in the tape drive continue to stream the tape for a predefined distance past the turn around point. The head may then be moved transversely to acquire a new track. The tape may then be spooled in the reverse direction on the new track. When a wrap point is encountered, the write current may be turned on and the next track (wrap) may be written. This combination of steps may be repeated for each serpentine wrap on the tape.

Abstract: A method and apparatus for reducing seek acoustics in a disk drive using feedback during large current transitions is provided. A desired transition profile, which uses feedback, is followed in order to smoothen transitions of a commanded current profile that is supplied to a VCM for moving a head relative to a disk surface during a seek operation. Linear interpolation is used to provide feedback for following the desired transition profile.

Abstract: A method for secondary-actuator failure-detection and recovery in a dual-stage actuator disk drive includes running a calibration test by the servo control processor and measuring the position of the secondary actuator relative to its neutral position in response to the calibration test. The secondary-actuator failure detection and calibration test can be performed on a regular schedule or at selected times, such as at disk drive start-up. With the primary actuator maintaining the read/write head on a data track in track-following mode, the servo control processor generates a test signal to the secondary actuator and receives a relative-position signal (RPS) from the relative-position sensor in response to the test signal. The test comprises two measurements: a measurement of the secondary actuator static characteristics, and a measurement of the secondary actuator dynamic characteristics.

Abstract: A method and apparatus for providing a marker at the end of the adaptive self-servowrite process for adaptive formatting via the self-servowrite process. The mark is used later in the drive manufacturing process to identify the number of tracks written on the surface and thus determine the appropriate format to use in the drive.

Abstract: A method in a dual-stage actuator disk drive tests if the secondary actuator has failed while the disk drive is in its normal track-following operating mode. The secondary actuator is removed from the control loop and the primary actuator maintains the read/write head on a data track in the track-following mode. The servo control processor generates a test signal to the secondary actuator and receives the position error signal (PES) as the read head detects the PES bursts in the data track being followed. The servo control processor calculates the response of the secondary actuator to the test signal by deconvolving the motion of the primary actuator from the PES. The calculated response is then compared with an expected response to determine if the secondary actuator has failed. The coherence function can be calculated to measure the statistical validity of the calculated secondary-actuator frequency response.

Abstract: A disk includes an actuator assembly, a spindle motor and a disk that defines a plurality of servo wedges. A wedge to wedge timer is configured to measure the time elapsed between at least two circumferentially adjacent servo wedges and to output a wedge to wedge correction signal that defines a count between circumferentially adjacent servo wedges that is dependent upon the measured elapsed time. A servo frequency generator is configured to output a servo frequency generator signal having a frequency that is modulated by the wedge to wedge correction signal. A spindle motor control timer outputs a spindle control timer signal that is dependent upon the servo frequency generator signal and upon the time elapsed between at least two successive detections of circumferentially adjacent servo wedges. A spindle motor controller controls the spindle motor with a control signal that changes according to the spindle control timer signal.

Abstract: A dual-stage actuator disk drive uses a secondary-actuator failure-detection and calibration test run by the servo control processor and a relative-position sensor for measuring the position of the secondary actuator relative to its neutral position in response to the calibration test. The secondary-actuator failure detection and calibration test can be performed on a regular schedule or at selected times, such as at disk drive start-up. With the primary actuator biased at a test location, such as a crash stop or a load/unload ramp, the servo control processor generates a test signal to the secondary actuator and receives a relative-position signal (RPS) from the relative-position sensor in response to the test signal. The test comprises two measurements: a measurement of the secondary actuator static characteristics, and a measurement of the secondary actuator dynamic characteristics.

Abstract: Managing temperature of a read/write head (120) in a disk drive system in which there is a power variance due to different operation modes. A circuit device (100) determines and delivers additional power needed for compensating for the temperature variance due to different operational power requirements. The power is delivered to a resistive heater (Rheat) associated with the head (120). The compensating power is based on the delivery voltage, delivery current, and resistance of the resistive heater (Rheat). The delivery current is varied to account for changes in the resistance of the resistive heater (Rheat) since it can vary with temperature. By sensing the current with a sensor (13), the resistance is determined via the sensed current and the delivery voltage. The current is adjusted for maintaining the compensating power.

Abstract: Detecting of a lower limit of tape head travel in a single reel tape drive discontinues signaling a tape head to move downward during initialization when the tape head as reach the lower limit of travel. Upon initialization, a processor steps the tape head housing to the lower limit of travel. A mechanical link at the bottom of the tape head engages a tape guide within a tape path and moves the tape guide away from the tape head. Movement of the tape guide pulls additional takeup leader from the takeup reel which rotates the guide rollers within the tape path. A tachometer coupled to one of the guide rollers within the tape path adjust a tachometer count which is monitored by the processor. In response to the change in the tachometer count, the processor discontinues stepping the tape head housing downward.

Abstract: First, data is read from tracks formed on a tape-shaped recording medium by heads disposed on a rotary drum, to measure error rates. Next, of the tracks formed on the tape-shaped recording medium, a worst track suffering the highest error rate is detected based on the error rates thus measured. Then, a pair of reproducing heads that can reproduce the worst track thus detected at the lowest error rates is detected from the measured error rates. Thereafter, tracking servo control is performed such that the worst track can be scanned by the pair of reproducing heads. As a result, a reproducing apparatus capable of proper reproduction even when recorded tracks undergo variations in width and reproducing heads are erroneously mounted.

Abstract: A retract circuit (40) for retracting a data transducer carriage assembly (17) of a mass data storage device (10) to a retracted position has a digital state machine (55) that is user programmable to operate in a selected retract mode. An analog control circuit (44) is provided for receiving control signals from the digital state machine (55) for providing analog retract signals to move the data transducer carriage assembly (70). The digital state machine (55) is user programmable to operate in constant voltage, velocity detect, float and pulse, and crash stop detect modes. Preferably, the digital state machine (55) is programmed to detect a velocity of the data transducer carriage assembly (17). The digital state machine (55) also is preferably programmed to detect an error velocity of the data transducer carriage assembly (17) from a difference of a measured voltage across the data transducer driver (22) from a predetermined voltage.

Abstract: A miniaturized library device is provided. The library device employs small-sized magazine having no flag used to detect positions of cells and the magazine is set so that a plurality of cells are arranged in one direction. An accessor mechanism having a picker mechanism to extract a cartridge from an arbitrary cell in the magazine is so mounted as to be movable along a guide rail and is positioned to a position of each of flags, which are arranged to correspond to positions of the cells in the magazine, and of a sensor flag section in a pendulum mechanism. The flags and a sensor flag section each are detected by a common X position sensor fixed to a base. Detection of presence or absence of the magazine is performed by detecting a position of the sensor flag section being displaced due to direct contact of a directly-contacted portion to the magazine.

Abstract: Disclosed is a disk drive that provides for internal disk drive temperature estimation. The disk drive includes an actuator, a head attached to the actuator, a disk to store data, a preamplifier connected to the head to amplify read and write signals, and a processor for controlling operations in the disk drive including moving the actuator such that the head is moved to read data from and write data to the disk. The processor under the control of a program is further utilized to calculate a junction temperature (JTemp) based on a breakthrough voltage of the preamplifier, apply a filter to the calculated JTemp to compensate for temperature noise, and to estimate an internal disk drive temperature based upon the filtered JTemp.