Abstract: A motion system and method of managing health of the motion system uses at least one multi-dimensional motor operational parameter (MOP) model and motion variables used by a servo drive of the motion system to calculate at least one health indication value for the motion system. The health indication value is used to generate a notification for maintenance of the motion system.

Abstract: A faulty tracking condition affecting a first head driven by a first actuator of a hard disk drive is determined. The faulty tracking condition is caused by a second actuator of the hard disk drive that is moving while the first actuator is performing a tracking operation. Responsive to the determination of the faulty tracking condition, seek forces of the second actuator that cause the faulty tracking condition affecting the first head are reduced. A controller verifies that similar faulty tracking conditions are reduced with the first head in response to the reduction in seek forces.

Abstract: A storage device includes a storage medium, a magnetic recording head, and a controller configured to operate the magnetic recording head to write consecutive data tracks at a uniform written track width and further configured to write data to alternating data tracks of the consecutive data tracks prior to writing data to at least one track interlaced with the alternating data tracks.

Abstract: An apparatus includes a transmission system configured to transmit a drive signal to a touch screen device. The apparatus also includes a reception system configured to integrate an output signal received from a touch screen device in response to the drive signals and to filter the integrated output signal to suppress noise in the output signal, wherein the reception system is configured to integrate the output signal for a period of time that is less than or equal to a signal period corresponding to the drive signal.

Abstract: The rotary drive system includes: a direct voltage source (102); an electric motor (104) having an axis of rotation (A), and including independent phases having directions about the axis of rotation; an inverter (106) for connecting each phase to the direct voltage source (102); and a control device (110) for supplying a command to the inverter (106). The control device includes: elements (118) for selecting a formula from predefined formulas, each predefined formula being intended to calculate either a homopolar voltage set-point, or a homopolar current set-point; elements (124) for determining a set-point intended to apply the selected formula to determine, according to the formula selected, either a homopolar voltage set-point, or a homopolar current set-point, and elements (126) for determining a command intended to determine the command of the inverter (106) based on the set-point determined.

Abstract: A data storage device is disclosed comprising a first head actuated over a first disk surface comprising servo tracks defined by full servo sectors, and a second head actuated over a second disk surface comprising servo tracks defined by mini servo sectors. At least part of a track address is read from one of the full servo sectors to generate at least one high order bit of a full track address, and at least part of a track address is read from one of the mini servo sectors to generate at least one low order bit of the full track address. The high order bit and the low order bit are combined to generate at least part of the full track address, and during an access of the second disk surface, the second head is servoed over the second disk surface based on the full track address.

Abstract: Provided are a computer program product, system, and method for determining a skew error signal (SES) offset used to determine an SES to adjust heads in a drive unit. A determination is made of a first difference in a first orientation with respect to a direction of movement of the recordable storage media based on first and second position information read by first and second servo read elements on a first head. A determination is made of a second difference in a second orientation with respect to the direction of movement of the recordable storage media based on third and fourth position information read by the first servo read element and a third servo read element on a second head. An offset, calculated based on the determined first and second difference, is used to generate an error signal to adjust the first and second heads.

Abstract: An apparatus includes: a media; a head over the media; and control circuitry configured to cause the head to: write a first precondition track with a preconditioning pattern on the media, and write a data track on the media at a first inter-track spacing with the head positioned in a first direction from the first precondition track.

Abstract: Determining the radial position of a first read head of a storage device includes reading servo data from a storage media platter surface using the first read head, deriving from that servo data a first positron error signal representing a first estimate of the radial position of the first read head, reading the servo data from the storage media platter surface using a different read head, deriving from that servo data a second position error signal representing an estimate of the radial position of the different read head, and combining the first estimate of the radial position of the first read head and the estimate of the radial position of the different read head to obtain a revised estimate of the radial position of the first read head. The combining could include taking account of a known positional offset between the first read head and the different read head.

Abstract: A disk drive is disclosed comprising a disk comprising a plurality of servo tracks, wherein each servo track comprises a plurality of servo sectors. A position of the head is measured based on the servo sectors, and a compensated position of the head is generated based on the measured position of the head and a fly height of the head. The head is actuated over the disk based on the compensated position of the head.

Abstract: The embodiments disclose an orientation control bias point coupled to a magnetic index mark and having a bias point offset set at predetermined coordinates configured to substantially prevent concentricity run-out.

Abstract: Various embodiments provide a recording medium. The recording medium may include a dedicated servo layer for providing servo information. The dedicated servo layer may include a plurality of tracks. A first track may include a first servo signal. A second track may include a second servo signal. The first servo signal and the second servo signal may include a plurality of common transitions. The transitions may be provided at a pre-determined frequency.

Abstract: A first portion of a track identifier is read from a first servo wedge of a track of a magnetic disk. A second portion of the track identifier is read from a second servo wedge of the track. The second portion includes least-significant bits of the track identifier that are also stored in the first portion. The first and second portions are combined to determine the track identifier for the first and second servo wedges, and the track is identified using the track identifier.

Abstract: Systems and methods are provided for throughput optimization of a hard disk drive (HDD) using position error signaling (PES) that includes determining a PES for a HDD mounted in a chassis based on a dynamic disturbance. The method also includes calculating a critical parameter of the PES. The method further includes indicating a mechanical design modification of the HDD or the chassis if the critical parameter of the PES exceeds a pre-defined threshold.

Abstract: A magnetic disk device includes a magnetic disk, a head and a control section. The head writes data to the magnetic disk. The control section controls the head to move along a virtual circular orbit of the magnetic disk that includes a first servo sector region and a second servo sector region. The second servo sector region has a larger servo interval than the first servo sector region, and stores a larger number of write bits than the first servo sector region.

Abstract: A disk drive is disclosed comprising a first head actuated over a first disk surface and a second head actuated over a second disk surface. A first servo sector of the first disk surface is read to generate a read signal which is processed to generate a first phase error. A first clock is generated at a frequency proximate a servo data rate of the first data sector. Read signal samples are synchronized in response to the first phase error and the first clock to generate synchronous samples, and servo data in the first servo sector is detected in response to the synchronous samples. The read signal is processed to generate a second phase error, a second clock is generated in response to the second phase error, and a spiral servo track is written to the second disk surface using the second clock.

Abstract: According to one embodiment, a magnetic disk drive includes a disk, a first microactuator, a second microactuator and a servo controller. The disk comprises a first surface and a second surface. The first and second microactuators allow first and second heads associated with the first and second surfaces to make micromotion based on first and second operation amounts, respectively. The servo controller provides a third operation amount to the first microactuator as the first operation amount and provides an operation amount obtained by inverting a polarity of a frequency component with a particular frequency contained in the third operation amount, to the second microactuator as the second operation amount, if the third operation amount is generated as an operation amount to be provided to the first microactuator in a particular mode in which the first surface is used as a tracking surface.

Abstract: A servo master having a pattern capable of being magnetically transferred as a servo pattern to a magnetic recording medium, wherein the servo master is formed of a material having a magnetic anisotropic constant perpendicular to a surface of the magnetic recording medium. The magnetic transfer method can include preparing a servo master patterned with a servo pattern to be formed on a magnetic recording medium, and arranging the servo master on the magnetic recording medium and applying an external magnetic field to the servo master in a first direction perpendicular to a recording surface of the magnetic recording medium, and in a second direction parallel to the recording surface of the magnetic recording medium.

Abstract: Systems and methods for flexure based shock and vibration sensor for head suspensions in hard disk drives. Specifically, this invention deals with operational shock and vibration management within a hard disk drive. In one implementation, the assembly includes a circuit embedded optical waveguide sensor that includes a flexible electrical circuit board with a configuration of either a single or multi layers of conductor traces, a thin flexure gimbal for carrying and flying a HDD slider, a consecutive sensing layer constructed by an optical core and by clad construction with a configuration of either a single core array or a plural core array, an optical loop formed by light input and an output core, optical grating disposed on the consecutive sensing layer forming an optical grating waveguide sensor, a light emitter for injecting light into the optical core, and a receiver receiving the output light from the optical core.

Abstract: Various approaches that reduce the width variability of storage media data tracks are described. First and second data tracks are written so that the second track overlaps the first track. After writing the second track data to the second track, an effective width of the first track is determined. The effective width of the first track is the portion of the first track that is not overlapped by the second track. One or more additional write operations to the recording medium are performed to compensate for the effective width of the first track being less than a threshold. The additional write operations may include one or more of rewriting the first track data to a third track on the storage medium and writing additional redundancy information to supplement the coding of the first track data.

Abstract: Systems and methods for flexure based shock and vibration sensor for head suspensions in hard disk drives. Specifically, this invention deals with operational shock and vibration management within a hard disk drive. In one implementation, the assembly includes a circuit embedded optical waveguide sensor that includes a flexible electrical circuit board with a configuration of either a single or multi layers of conductor traces, a thin flexure gimbal for carrying and flying a HDD slider, a consecutive sensing layer constructed by an optical core and by clad construction with a configuration of either a single core array or a plural core array, an optical loop formed by light input and an output core, optical grating disposed on the consecutive sensing layer forming an optical grating waveguide sensor, a light emitter for injecting light into the optical core, and a receiver receiving the output light from the optical core.

Abstract: A magnetic storage medium comprises a plurality of discrete magnetic elements and first and second adjoining servo sectors. Each of the servo sectors comprises first and second rows of the discrete magnetic elements extending in a track direction. The second row of the discrete magnetic elements are stacked relative to the discrete magnetic elements of the first row in a cross-track direction that is perpendicular to the track direction. The discrete magnetic elements of the first servo sector are staggered in the cross-track direction relative to the discrete magnetic elements of the second servo sector.

Abstract: Servo-related tasks are performed at a first processor in a disk drive. A signal indicative of an environmental condition is received at the first processor, and code associated with the environmental condition is identified based at least in part on the signal. A second processor in the disk drive is caused to execute the code associated with the environmental condition, and a responsive task is performed at the first processor based at least in part on the executed code associated with the environmental condition.

Abstract: According to one embodiment, a recording device comprises: a recording medium, an arm, a positioning module, a self-servo write clock generator, and an on-track module. The positioning module positions the arm at a position at which the electromagnetic transducer detects a rotational synchronization component of an intermediate pattern comprised in the recording medium. The self-servo write clock generator generates a self-servo write clock based on the detected rotational synchronization component. The on-track module positions the electromagnetic transducer to the intermediate pattern serving as a position for starting self-servo write based on the generated self-servo write clock. Until the on-track module appropriately completes the positioning, the self-servo write clock generator sequentially changes a decoding gate interval corresponding to the intermediate pattern in accordance with the rotational synchronization component, and captures a spiral reproduction waveform.

Abstract: A storage apparatus includes a magnetic storage medium which is formed with a data portion based on isolated magnetic dots and a servo pattern portion, a drive mechanism which drives the storage medium, a head actuator which includes a head for reading and writing data from and to the storage medium, and a permanent magnet which is disposed at a position that is opposable to a whole radial region of the servo pattern portion, during a rotation of the storage medium.

Abstract: A magnetic recording disk drive has a disk with a head positioning servo pattern of multiple circumferentially-spaced chevron patterns of discrete patterned servo islands. The disk drive has servo electronics that decodes the chevron patterns to determine the absolute radial position of the head without the need for separate track identification fields. The chevron pattern with the smallest radial period has a radial period P1 and each of the other chevron patterns has a period which is a unique multiple of P1. In one embodiment the first chevron pattern read by the head has period P1 and each successive chevron pattern read by the head has a period that is greater than the period of the chevron pattern immediately preceding it such that the period of each chevron pattern progressively increases.

Abstract: At time to start learning feed-forward control and under the status that servo-drive is not put in execution, a positioning error of repeatable runout is detected by means of a positioning error of repeatable runout operation section and on the basis of a value of the positioning error of repeatable runout, a drive pattern and drive interval of idling are determined by means of a feed-forward data operation section. The drive pattern is stored in a feed-forward data memory and is outputted as feed-forward data in synchronism with the rotation of a spindle during drive interval, thus performing idling of a fine-movement actuator. After the idling has ended, control initiation sequence is resumed to carry out learning of feed-forward control.

Abstract: A method to position a head module, where the head module comprises at least one servo element and a plurality of data elements, where the servo element and each of the plurality of data elements can detect a servo signal, wherein the method includes moving a sequential information storage medium having a servo band encoded therein across the head module and detecting the servo band using the at least one servo element or any one of the plurality of data elements.

Abstract: A hard disk drive using an increase in servo address mark delays to create a touchdown flag in response to a slider making contact with a rotating disk surface while accessing a track. This may be used particularly when the track being accessed is located away from the Inside Diameter (ID). The hard disk drive may further use resistive heater electrical readings to determine the touchdown flag for track locations near the ID. The hard disk drive may be calibrated during manufacture and/or may be recalibrated in the field with this method. The calibrated hard disk drive is a product of this method. The method may be used during normal access operations and/or may be embodied as a program system residing in computer readable memory for instructing a computer operating the hard disk drive, where the computer and/or the memory may or may not be included in the hard disk drive.

Abstract: A weighted combining scheme exploits information from two servo channels operating in parallel. A timing-based servo module servo module comprises two servo channels coupled respectively to receive two digital servo signals read from a data tape. Both channels have outputs for an unweighted metric and for a measure of the channel reliability. A weight computation module provides first and second weight signals using the measures of channel reliability from the servo channels. A first multiplying node receives a first unweighted metric and a first weight signal and is operable to output a first weighted metric. A second multiplying node receives a second unweighted metric and a second weight signal and outputs a second weighted metric. A summing node receives the first and second weighted metrics and outputs a combined weighted metric to an LPOS word decoder.

Abstract: A magnetic recording disk has patterned nondata regions that are used for read/write head positioning and data synchronization. The nondata regions contain nondata islands of magnetizable material separated by nonmagnetic spaces with the nondata islands having alternating magnetization polarity in the along-the-track direction. In each nondata region, every other nondata island in the along-the track direction has the same magnetization direction, with adjacent nondata islands having antiparallel magnetization directions. The disk may be either a horizontal magnetic recording disk, wherein the antiparallel magnetization directions are in the plane of the recording layer and parallel to the along-the-track direction, or a perpendicular magnetic recording disk, wherein the antiparallel the magnetization directions are “into” and “out of” the recording layer.

Abstract: A disk drive is disclosed comprising a disk having servo data defining a plurality of servo tracks. The servo data comprises a preamble, and a plurality of slanted line servo bursts recorded at a tilt angle with respect to the preamble. The slanted line servo bursts comprises a first plurality of slanted line servo bursts and a second plurality of slanted line servo bursts, wherein the second plurality of slanted line servo bursts are offset radially from the first plurality of slanted line servo bursts. A position error signal (PES) is generated in response to a phase difference when reading the preamble and the slanted line servo bursts.

Abstract: A servo write method for a hard-disk drive. The method includes generating, with an input of characteristics of a magnetic-recording head and a magnetic-recording disk which are incorporated into the hard-disk drive, a yield prediction model from a correlation between yields of the hard-disk drive, and characteristics of the magnetic-recording head and the magnetic-recording disk of the hard-disk drive in a process. The method also includes predicting a yield which is obtained when each magnetic-recording head is used as a position control head, selecting as the position control head a magnetic-recording head that has a highest predicted yield, and writing a servo signal.

Abstract: According to one embodiment, an information storage apparatus, includes: a recording medium with a first servo pattern having absolute position information and a second servo pattern having relative position information; a record reproducing head; a standard position detector calculating a standard position of the second servo pattern where an absolute position on the recording medium is specified, from a positional relationship between the first servo pattern and the second servo pattern; a head position controller positioning the record reproducing head in a target position on the recording medium, using the absolute position information of the first servo pattern, the standard position, and the relative position information of the second servo pattern; and a record signal generator generating a record signal to record a third servo pattern having absolute position information on the recording medium in the target position by the record reproducing head.

Abstract: A method for writing servo onto a disk of a hard disk drive with a servo writer. The method includes writing a plurality of spiral servo signals onto a disk. The spiral servo signals include a plurality of short spirals separated by unequal distances. The short spirals are detected by determining the unequal distances and used to write a plurality of servo patterns. The unequal distances provide information of the short spirals at different quadrants of the disk. The distances between a bank of odd short spirals is different than a bank of even short spirals which allows the servo writer to determine whether the bank is odd or even without switching banks. Either the even or odd bank of short spirals can be used to locate a starting reference point from which the servo writer can count spirals and write A, B, C and D servo bursts.

Abstract: A servo writer includes a servo data generation module that generates servo data corresponding to a plurality of servo wedges and a plurality of tracks of a disk, the servo data including burst data that is repetition coded. A servo write module writes the servo data on the disk.

Abstract: A method for writing servo onto a disk of a hard disk drive with a servo writer. The method includes writing a plurality of spiral servo signals onto a disk. The spiral servo signals include a plurality of short spirals separated by unequal distances. The short spirals are detected by determining the unequal distances and used to write a plurality of servo patterns. The unequal distances provide information of the short spirals at different quadrants of the disk. The distances between a bank of odd short spirals is different than a bank of even short spirals which allows the servo writer to determine whether the bank is odd or even without switching banks. Either the even or odd bank of short spirals can be used to locate a starting reference point from which the servo writer can count spirals and write A, B, C and D servo bursts.

Abstract: A servo master having a pattern capable of being magnetically transferred as a servo pattern to a magnetic recording medium, wherein the servo master is formed of a material having a magnetic anisotropic constant perpendicular to a surface of the magnetic recording medium. The magnetic transfer method can include preparing a servo master patterned with a servo pattern to be formed on a magnetic recording medium, and arranging the servo master on the magnetic recording medium and applying an external magnetic field to the servo master in a first direction perpendicular to a recording surface of the magnetic recording medium, and in a second direction parallel to the recording surface of the magnetic recording medium.

Abstract: A servo writer includes a servo data generation module that generates servo data corresponding to a plurality of servo wedges and a plurality of tracks of a disk, the servo data including track identification data that is repetition coded. A servo write module writes the servo data on the disk.

Abstract: A method of forming a reference pattern. The method includes: determining whether a boundary point of an initial reference pattern is located at an inner diameter region of a disk, which is inside an outermost circumferential track; and if the boundary point of the initial reference pattern is located at the inner diameter region of the disk, additionally forming a compensated reference pattern integrally with the initial reference pattern so that a final reference pattern extends in the direction of an outer diameter of the disk. The method allows compensation for a defective reference pattern into an effective reference pattern by extending the initial reference pattern according to whether the boundary point of the initial reference pattern is located inside the outermost circumferential track of the disk.

Abstract: A hard disk drive that includes a head that is coupled to a disk. The head has a flying height and an inductance. The disk drive also includes a circuit that detects a change in the flying height by sensing a change of head inductance. The circuit can inhibit a write operation if the change in inductance exceeds a threshold.

Abstract: A magnetic disk for a hard disk drive comprising a distributed track identifier is described. The disk includes a first portion of a track identifier physically located at a first location on a disk sector and a second portion of the track identifier physically located at a second location on the disk sector wherein the first portion and the second portion of the track identifier are discontinuous on the sector.

Abstract: According to one embodiment, a disk drive has a DTM type disk. The DTM type disk has a servo area on one recording surface. In the servo area, a servo pattern is recorded. The servo pattern is composed of a projection-depression pattern and an N- and P-pole magnetic pattern. The N- and P-pole magnetic pattern is recorded in an address-data region that contains a cylinder code.

Abstract: A gain controller changes a gain of a read amplifier depending on whether a head reads out servo data or user data. Further, a heater setting unit changes the temperature of a heater and a reading gain when detecting touchdown performed by the head. Accordingly, a dynamic range of AGC in a read-write channel is increased, so that error detection is prevented for touchdown that occurs because an AGC gain converged value remains at 0.

Abstract: An information storage apparatus that records servo information and user data on a recording face of a recording medium wherein a track density measuring unit measures the optimal track density for a recording face corresponding to each head targeting a storage medium on which the servo information has not yet been recorded and a recording density measuring unit measures the optimal linear density for each recording face. A servo frame writing unit writes the servo information varying a track pitch to a track pitch corresponding to the optimal track density measured by the track density measuring unit and a recording frequency to a recording frequency corresponding to the optimal linear density measured by the linear density measuring unit, for each head.

Abstract: According to one embodiment, in a disk drive using a disk medium storing spiral servo information, a CPU generates virtual servo information having assumed virtual track centers corresponding to centers of concentric data tracks. The CPU performs control to position a head to the center of the concentric data track by using the virtual servo information.

Abstract: Techniques are provided for identifying the servo sectors in a track on a data storage device. A data storage device identifies the servo sectors in a track by reading distributed index bits from multiple servo sectors in a track. The data storage device analyzes only one index bit from each servo sector to identify the index of a track. In some embodiments, the index of a track can be identified after examining the index bits stored in a particular number of consecutive servo sectors, even in the presence of errors. The index bits in each track can have an error tolerance with a minimum Hamming distance greater than one. In other embodiments, a data storage device compares a sliding window of the index bits read from the servo sectors to all possible N-bit vectors that exist within a pattern of the index bits stored on a track.

Abstract: On an information recording medium, a data track pattern and a servo pattern composed of a concave/convex pattern including a plurality of convex parts are formed on at least one surface of a substrate and respective concave parts in the concave/convex pattern are filled with non-magnetic material. In the concave/convex pattern that constructs the servo pattern, a unit convex part length along a direction of rotation of the substrate and a unit concave part length along the direction of rotation are set so that the ratio of the unit convex part length to the unit concave part length decreases from an inner periphery to an outer periphery of the information recording medium.

Abstract: A method for writing servo information onto a disk of a hard disk drive with a servo writer. The method includes accelerating a head to a constant velocity across a disk. The disk being defined as having an acceleration zone and a constant velocity zone. The head is then used to write a spiral servo pattern in the constant velocity zone. A final servo pattern is written in the constant velocity zone using the spiral servo pattern. A servo reference pattern is also written in the acceleration zone. The servo reference pattern is used to write a final servo pattern in the acceleration zone. The final servo pattern may be copied using a run-out cancellation algorithm to improve the accuracy of the servo pattern in the acceleration zone.

Abstract: According to one embodiment, there is provided a servo write method of writing specified servo patterns to a disk medium on the basis of a spiral servo pattern recorded on the disk medium, wherein when the spiral servo pattern is read using a head, position detecting data used to detect a radial position on the disk medium on the basis of data recorded in a sync mark region.