Abstract: A method and apparatus are provided for implementing in situ low flyheight warning in a direct access storage device (DASD). For each head in the DASD, a readback amplitude ratio is identified from two different disk radii. The initial ratio value is stored for each head in the DASD. During operation of the DASD, readback amplitude is monitored and an operating readback amplitude ratio is identified from two different disk radii. A change between the initial ratio value and the operating readback ratio is calculated and compared with a threshold value to identify a low-flying slider. A warning is generated responsive to the change value being greater than the threshold value.

Abstract: A method and apparatus for detecting lubricant depletion in a disk drive is provided. Disk operation performance parameters are monitored for each of a plurality of zones on the surface of the disk and stored. Examples of performance parameters include dwell time, flying height changes, and data recovery measurements. The performance parameters are compared against predetermined threshold values. If the performance parameters exceed the predetermined threshold values for any of the zones, a potential lubricant depletion or other general degradation problem is flagged for the corresponding zone. Optionally, when a potential lubricant depletion problem is flagged for a particular zone, corrective action is taken. Examples of corrective action include moving recently accessed data from the flagged zone to a zone not identified as having a lubricant depletion problem, moving older archival data to the flagged zone, and/or removing access to the flagged zone.

Abstract: A method of burnishing a rear pad of a slider within a disk drive. The rear pad is formed of a burnishable material and maintains elements for reading and writing. The disk drive further includes a spindle motor rotatably driving a disk and an actuator assembly positioning the slider over a surface of the disk. With this in mind, the method includes rotating the disk. The slider is moved in a radial fashion relative to the disk surface in a reciprocal fashion, causing the rear pad to rock. As the rear pad rocks, contact between the rear pad and the disk surface burnishes the rear pad. As a result, a positive camber is imparted in the rear pad relative to the MR element. The above-described method can be practiced following initial manufacture of the disk drive, or at various times over the life of the disk drive. Regardless, the method is practiced in-situ and is therefore very fast, cheap, and adapts quickly to the particular disk in which the slider is flying.

Abstract: A method and apparatus are provided for implementing intelligent spin-up for a disk drive. When a command is received, checking for a disk drive start command is performed. Responsive to identifying the disk drive start command, a no-start flag is checked. Responsive to identifying the no-start flag being set, an error code is returned without starting the disk drive. The disk drive is started only when the no-start flag is not set. During operation of the disk drive, the disk drive is monitored to identify a drive fault condition. Responsive to identifying a disk drive fault, the identified disk drive fault is checked to identify a predefined inoperative drive or dead device fault. When a predefined dead device fault is identified, the no-start flag is set and an error code for the predefined dead device fault is stored. Also a no-load flag is set that is used when the disk drive is running to stop the disk drive and return an error code before the transducer heads are loaded.

Abstract: A method for accessing remote information via a personal digital device, the method including the steps of storing embedded information in a memory of the personal digital device, receiving an information query from a user of the personal digital device, and determining if a response to the information query is contained in the embedded information. If the response to the information query is contained in the embedded information, then the embedded information is displayed to the user. Alternatively, if the response to the user query is not found in the embedded information, then a remote information query is executed through a wireless communication device. Additionally, if a remote information query is executed, the method includes the step of storing parameters representing the information query.

Abstract: The microwaviness (i.e., surface waviness for wavelengths on the order of the length of the transducing head) of a recording disk surface is measured during manufacture as a quality control process. Preferably, the disk is measured using an actuator-mounted thermal sensor, comprising an electrical resistance element driven with a constant current. At small distances, the disk surface acts as a heat sink and variation in this distance will be detected as a change in resistance of the sensor. Preferably the sensor is initially used to characterize the gross waviness of the surface, and the actuator then follows this gross waviness to measure surface variations in the microwaviness range.

Abstract: A method of burnishing a rear pad of a slider within a disk drive. The rear pad is formed of a burnishable material and maintains elements for reading and writing. The disk drive further includes a spindle motor rotatably driving a disk and an actuator assembly positioning the slider over a surface of the disk. With this in mind, the method includes rotating the disk. The slider is moved in a radial fashion relative to the disk surface in a reciprocal fashion, causing the rear pad to rock. As the rear pad rocks, contact between the rear pad and the disk surface burnishes the rear pad. As a result, a positive camber is imparted in the rear pad relative to the MR element. The above-described method can be practiced following initial manufacture of the disk drive, or at various times over the life of the disk drive. Regardless, the method is practiced in-situ and is therefore very fast, cheap, and adapts quickly to the particular disk in which the slider is flying.

Abstract: An apparatus, method and program product are operable for controlling the operation of a disk drive in a computer subjected to motion, and comprise monitoring the motion of the computer and detecting multiple successive forces on the computer caused by the motion. Based upon characteristics of the detected forces, a motion condition, such as a walk or non-walk condition is determined. Disk drive operations are then scheduled based on the motion condition so that the scheduled disk drive operations significantly avoid occurrence during one of the future motion forces and accelerations.

Abstract: The present invention provides a method and apparatus for detecting the presence of contaminants on the slider of a disk drive. By detecting the rate of change of the resistance of a thin film coil of a disk drive write element during drive operation, it can be determined if a foreign material is present on the coil. Nominal resistance change values for write elements of a disk drive are determined at manufacturing time, and are stored within the disk drive. During later operational use, the resistance change for the coil of the write elements is measured and compared with the stored nominal resistance change values. If the difference between the stored nominal resistance values and the measured resistance change values exceeds a predetermined threshold, the drive is presumed to have contaminants on the slider.

Abstract: A disk for a disk drive data storage device contains embedded track identifying fields which identify a track within a range of tracks, the range being less than the full range of tracks on the disk surface. The full identity of a track during a track seek operation is determined by iteratively assuming a track identity and estimating acceleration of the transducer based on the assumed track identity, until a track identity is found for which estimated acceleration meets some pre-determined threshold. Preferably, embedded servo fields are recorded at angularly spaced intervals on the disk surface, and every Nth servo field contains a Gray code full track identifier, while all servo fields in between contain abbreviated Gray code fields which identify a track within a range of tracks.

Abstract: A method and apparatus for estimating the flyheight of an airbearing slider in a storage device. The slider floats on an airbearing over a rotating storage disk. The storage disk includes a washboard-sequence having washboard-sections each comprising surface profile variations having a different pitch. The pitches are selected from within a range of values likely to excite an airbearing resonance of the slider as the storage disk rotates at a rated storage disk velocity. For each of the washboard-sections, a maximum amplitude of flyheight modulation of the slider resulting from the slider floating over that washboard-section is measured. A determination is made of which washboard-section caused the largest measured flyheight modulation. The washboard-section having a pitch that provides an excitation frequency (when the disk is rotated at the rated storage disk velocity) that is closest to the actual airbearing resonance frequency of the slider will produce the largest flyheight modulation.

Abstract: An apparatus and method shares predictive failure information between computer system in a computer network. The shared predictive failure information allows dynamically rerouting a network request to avoid a computer system that may fail according to its predictive failure information. According to a first embodiment, if the requested resource on the network has predictive failure information that indicates the resource may soon fail, a message is returned to the requesting computer with information that includes possible alternative sites from which the information may be obtained. If there is an alternative site, the requesting computer system may access the alternative site, thereby avoiding the computer system that may soon fail. If there is no alternative site, the requesting computer system may return an error message, or may simply access the original resource on the chance that is has not yet failed.

Abstract: An apparatus and method shares predictive failure information between computer system in a computer network. The shared predictive failure information allows dynamically rerouting a network request to avoid a computer system that may fail according to its predictive failure information. According to a first embodiment, if the requested resource on the network has predictive failure information that indicates the resource may soon fail, a message is returned to the requesting computer with information that includes possible alternative sites from which the information may be obtained. If there is an alternative site, the requesting computer system may access the alternative site, thereby avoiding the computer system that may soon fail. If there is no alternative site, the requesting computer system may return an error message, or may simply access the original resource on the chance that is has not yet failed.

Abstract: A method of evaluating a condition of a head-disk interface (HDI) of an operational disk drive. The disk drive includes at least one disk having a disk surface and at least one transducer head for writing and/or reading data from the disk surface. In this regard, the transducer head is sensitive to temperature changes. With this in mind, the method includes rotating the disk at an operational rate. A first thermal signal is received from the transducer head that is indicative of thermal activity at the transducer head. The first thermal signal is analyzed for thermal transients. Based upon this analysis, first thermal variation information indicative of a relationship of thermal transients in the first thermal signal relative to a baseline is generated. Finally, the first thermal variation information is compared to threshold information indicative of an acceptable HDI. In one preferred embodiment, a prediction of an impending head crash is made based upon the comparison.

Abstract: A magnetic disk drive is provided with clamping rings that whenever nested will form an annular chamber to accommodate a toroidal ring which is deformable. As the clamping rings are progressively forcefully engaged by the clamping rings, the chamber is reduced in height and transmits the force of the top clamping ring to the bottom clamping ring in a uniform distribution and prevents the force of the bottom clamping ring from having non-uniformity of distribution. This action prevents magnetically recordable disks of the disk drive from being subjected to point loading and consequential warping. The uniform distribution exerted on glass disks also prevents cracking or shattering of the glass disk and prevents warping of non-glass disks.

Abstract: A method and apparatus for estimating the flyheight of an airbearing slider in a storage device. The slider floats on an airbearing over a rotating storage disk. The storage disk includes a washboard-sequence having washboard-sections each comprising surface profile variations having a different pitch. The pitches are selected from within a range of values likely to excite an airbearing resonance of the slider as the storage disk rotates at a rated storage disk velocity. For each of the washboard-sections, a maximum amplitude of flyheight modulation of the slider resulting from the slider floating over that washboard-section is measured. A determination is made of which washboard-section caused the largest measured flyheight modulation. The washboard-section having a pitch that provides an excitation frequency (when the disk is rotated at the rated storage disk velocity) that is closest to the actual airbearing resonance frequency of the slider will produce the largest flyheight modulation.

Abstract: A recording disk contains at least two types of servo sector format, including a first type having a relatively larger track identifying field containing the track number, and a second type having an abbreviated track identifying field identifying a track within a range of tracks, the range being less than the full range of tracks on the disk surface. Preferably, Gray code encodings are used, the first type of track field contains sufficient Gray code bits to identify the ful track number, every Nth servo sector is of the first type, and all servo sectors in between are of the second type, N being at least 2. As a result, the disk area required for track identification is reduced, and the additional disk space available can be used to expand the PES field.

Abstract: In a first aspect, a method of operating a disk drive includes detecting a trigger event during non-idle operation of the disk drive, and responding to the detected trigger event by performing a predictive failure analysis with respect to the disk drive. According to a second aspect, a method of operating a disk drive includes performing a predictive failure analysis with respect to the disk drive at a regular time interval, detecting a trigger event during non-idle operation of the disk drive, and responding to the detected trigger event by reducing the regular time interval at which the predictive failure analysis is performed. Numerous other aspects are provided.

Abstract: A method and apparatus are provided for implementing adaptive reordering of data recovery procedure (DRP) steps in a direct access storage device (DASD). An initial set of DRP steps is stored. A reorder table is stored during the operation of the DASD. The reorder table includes data recovery data for each data head of successful predefined DRP step numbers. When a DRP process is started, checking for a modified DRP step is performed using the reorder table. Responsive to not identifying the modified DRP step, file parameters for a DRP read operation are set based on the initial set of DRP steps. Responsive to identifying the modified DRP step, file parameters for a DRP read operation are set based on a reordered DRP step that is identified by using the stored successful predefined DRP step numbers in the reorder table. When a successful DRP read operation is identified, the data recovery data in the reorder table are updated.

Abstract: A disk drive comprises an actuator servo control system including at least one disk, an actuator structure comprising at least transducer head for writing and/or reading data from the disk and providing a transducer head position error signal (PES), and a servo compensator applying a servo control algorithm to the PES to produce a servo control signal. An adaptive elliptic notch filter controller is adapted to analyze the PES for a transducer head at a disk track radii, identify resonant disturbances present in the PES, select two adjacent resonant disturbances having first and second frequencies, ascertain coefficients of at least a fourth-order elliptic notch filter transfer function having first and second zero-notches with frequencies substantially at the first and second resonant frequencies, apply the at least fourth-order elliptic notch filter transfer function with the ascertained coefficients in the servo system to thereby substantially attenuate the selected adjacent resonant disturbances.