Matches 151 - 200 out of 548 < 1 2 3 4 5 6 7 8 9 10 11 >
Match Document Document Title
6724561 Apparatus and method for compensating for environmental effects on media  
An apparatus and method for compensating for environmental effects on media. The apparatus includes an array of servo readers that are positioned at a non-zero azimuth angle relative to a medium....
6724560 Head assembly employing microactuator in recording medium drive  
A head suspension supporting a head at the tip end is allowed to swing at the tip end of a carriage in a recording disk drive. A microactuator is interposed between the head suspension and the...
6721122 Disk drive unit and control method for same  
A disk drive unit includes acceleration sensors mounted thereon. A sequence for calculating an amount by which a head actuator is adjusted during recording and readout operations is changed based...
6721121 In-situ determination of landing zone transition for improved disk drive reliability  
A data storage disk is formatted using a measured edge location of a textured landing zone as a reference for writing servo information to the surface of the disk. The edge of the textured landing...
6717761 Recording/reproducing apparatus  
A recording/reproducing apparatus capable of switching over among a plurality of heads with high precision, wherein the apparatus is provided with: a recording/reproducing unit for...
6710966 Method for reducing an effect of vibration on a disk drive during a track following operation by adjusting an adaptive-filter gain applied to an acceleration sensor signal  
The present invention may be embodied in a method, implemented in a disk drive, for adaptively reducing an effect of vibration during a track following operation. The disk drive includes a disk and...
6710965 Phase-advanced filter for robust resonance cancellation  
A filter for attenuating a resonance mode without substantial phase margin loss. The filter comprises a transfer function having an additional pole, such that the phase of the input signal is...
6707635 Method and apparatus for RRO learning on alternate tracks before and after shipping to cancel RRO in a disk drive  
The present invention may be embodied in a method, and related apparatus, for determining a repeatable runout (RRO) compensation value sets for a plurality of tracks on a disk in a disk drive,...
6707633 Magnetic disk device including coarse and micro actuators  
A magnetic disk device comprises at least a disk having information, at least a head for reading or writing information from or into the disk, at least a micro actuator for supporting the head and...
6690537 Method and system for controlling the positioning of a read/write head of a data recording device  
A read/write head servo control system for data recording devices, wherein a method of compensating initial values is utilized to generate a control signal to move the head from an initial position...
6690534 Method and apparatus for handling multiple resonance frequencies in disc drives using active damping  
A method of handling multiple resonance frequencies in a disc drive includes monitoring a position error signal (PES) for an actuator arm, generating a plurality of feedforward compensation signals...
6683737 Method and apparatus for predictive failure analysis technique for head crashes in hard drives using position error signal  
A position error signal indicative of the distance between an expected position of a magnetic head relative to the track centerline of a magnetic data storage and retrieval system and an actual...
6671790 Optimizing reader to writer offset compensation for a disc drive  
A method for optimizing logical track to physical track offset compensation of a data storage device includes steps of: associating each of a plurality of logical tracks to one of a plurality of...
6667840 Method for screening oscillatory PES with 1.7 kHz harmonic resonance  
The present invention provides a method to screen tracks on a magnetic disc in a disc drive for harmonic resonance. There are several algorithms in the method performing different functions at...
6665138 Technique for detecting head position in hard disk drive  
A technique for detecting a current position of a head of a hard disk drive detects the position of the head by using an analog-to-digital conversion value of a single crossing point of one of...
6661359 Device and method for generating synchronous numeric signals  
A device for generating synchronous numeric signals, including a reference generating device supplying a reference signal and a first timing signal, both having a reference frequency; and a timed...
6657805 Method of controlling read write operation of a magnetic disk apparatus  
When the amount of position error PE of a magnetic head meets the condition of Ewf>PE>=Eww for two threshold values Ewf and Eww meeting Ewf>Eww, the track is registered in the track...
6657801 Disk drive with improved characterization segment pattern and method of recording the same  
A disk drive and related method, the disk drive including a rotating magnetic disk and read and write elements for reading and writing data from and to the rotating magnetic disk, comprising: a...
6654195 Disk drive having a register set for providing real time position variables to a host  
A disk drive provides head position information as position status variables to a host. The position status variables are derived from information formatted on a disk and processed by a media...
6650491 System and method for setting a read/write offset and for recovering from data read errors  
An RW offset setting method which includes recording a test pattern by a write head, reading the test pattern by a read head, measuring an amplitude of a read back signal at each tracking position,...
6646824 Head-positioning control method and device for a disk device  
This invention relates to a head-positioning method and device for positioning the head, that reads a disk medium, to a specified position. A disk device having a head, actuator and control circuit...
6646823 Disk drive using offset data sectors  
A disk drive stores data within a single track of a data storage disk at two different lateral positions with respect to the track centerline. The radial distance between the two lateral positions...
6643084 Adaptive off-track recovery  
A method and system for adaptively limiting an off-track recovery displacement of a recording head during an off-track data recovery operation. A head disk assembly (HDA) includes an actuator that...
6636376 Disc drive resonance disturbance cancellation filter  
An apparatus and method for canceling nonrepeatable runout position error in a disc drive. Pursuant to the method, a frequency of a specified nonrepeatable runout disturbance is determined. A...
6636375 Seek in a disc drive with nonlinear pivot friction  
According to one embodiment of the present invention, a disc drive includes a disc and a transducer supported by an actuator assembly that is accelerated by controlling current in a voice coil. The...
6628471 Detection and cancellation of cage frequency using the clock head in a servowriter  
The magnitude and frequency of runout due to vibration of the cage of the spindle motor is detected. A plurality of servo patterns are written to a reference track having a clock pattern on the...
6618220 Head actuator and hard disc drive including the same  
A head actuator includes a head slider for carrying a head for recording information to or reproducing information from a recording medium; and a head supporting member for supporting the head...
6614614 Method and apparatus for writing servo pattern  
The invention relates to a method for writing servo patterns on a data recording disk of a disk drive device. A read/write head is stopped at a reference position on the data recording disk, then...
6614609 Gray code detection for a disk drive system  
A disk drive system is disclosed that includes a disk device coupled to control circuitry. The control circuitry includes a read channel with a detector that detects a bit sequence associated with...
6608731 Dynamic reduction of track shape errors in disc drives  
The invention eliminates relative and absolute track shape errors by writing zero acceleration path (ZAP) correction factors into the servo sectors during track propagation. A servo track guide...
6606214 System and method to minimize bearing pivot effect in disc drive actuator  
A disc drive is provided which incorporates a rotatable actuator which is mounted to a base of the disc drive through a pivot mechanism. The actuator positioning is controlled by a servo system and...
6606213 Actuator resonance screening in disc drives  
A disc drive system and method of screening an actuator resonance includes a servo controller providing a multi-servo zone architecture. The servo controller partitions the disc into a plurality of...
6600635 Combined magnetic data and burnish head for magnetic recording  
A data storage system capable of removing disk surface irregularities and/or contaminant particles on disk surfaces that may cause thermal asperities in the transducer output is provided. The data...
6580579 Disturbance rejection for disc drives using adaptive accelerometer feedforward servo  
A system and method for attenuating the effect of rotational vibration on the positioning of the read/write head in a disc drive. The rotational acceleration of the disc drive body is sensed and...
6577464 Magnetic recording device having first actuator for coarse adjustment and second actuator for fine adjustment  
In a magnetic recording device, a control element placed on a flexible wiring board between a control device and first actuators includes a plurality of actuator-driving-signal connecting terminals...
6570732 Method and apparatus for settling determination control systems  
A method and apparatus for a settling check based on a single time point is described. A settling criterion for head oscillations in a disc drive is calculated using head position data. The...
6560055 ID-less format defect management for automatic track processing including translation of physical sector number into logical sector number  
Defect management for automatic track processing without an ID field, processes defect information for a track on a magnetic media within a disk drive system. A system which uses any method of...
6556370 Method of writing tracking servo signal pattern for magnetic disk device  
A method of writing a tracking servo signal pattern for a magnetic disc device includes the steps of recording only a first burst signal and a second burst signal with a servo track writer for...
6549349 Adaptive vibration control for servo systems in data storage devices  
Methods and systems for detecting and correcting for undesirable vibrations impacting the servo systems in data storage devices. A detection technique is provided wherein a detection filter is...
6545835 Method and apparatus for RRO learning before and after shipping to cancel RRO in a disk drive  
The present invention may be embodied in a method, and related apparatus, for determining a repeatable runout (RRO) compensation value set for a track on a disk in a disk drive, wherein the disk...
6538839 Disk drive employing adaptive feed-forward vibration compensation to enhance a retry operation  
A disk drive is disclosed comprising a head, and an actuator, responsive to an adjusted control effort signal, for actuating the head radially over a disk. An adaptive feed-forward signal is...
6538836 Microactuator for fine positioning in a disc drive  
An actuator arm assembly is provided in a disc drive. The disc drive includes a disc with a surface for storing information and a first actuator for moving the actuator arm assembly relative to the...
6535347 Head controlling device in a disk apparatus  
A head-controlling device of a disk apparatus is provided that can precisely move a head stepwise to the position of each track on a recording surface of a disk. When detection output values A1 and...
6532130 Head for reading magnetically stored data  
A head ( 130 ) for a disk storage device having a plurality of tracks ( 117 ) divided into memory cells ( 234 ), including a magnetic circuit ( 205, 230 a, 230 b, 250 a, 250 b ) for reading the...
6532129 Method and apparatus for sustaining feedback filter state having periodic output  
A disk drive system, includes a head, a controller for controlling an operation of the head, at least one feedback filter coupled in relation to the controller, and a mechanism for keeping a...
6515818 Track follow at quarter track with narrow heads using non-conventional ordering of quadrature fields  
A method and apparatus for performing track follow and seeking at quarter track positions that uses a non-conventional ordering of the servo fields at the quarter track positions, wherein C−A or...
6510016 Head positioning control system for disk drive  
A positioning control system for a disk drive can reduce static friction of the sliding type actuator to be a cause of degradation of low order spindle rotation synchronization run-out. The...
6507449 Digital servo demodulator with synchronous dithering and method  
The effective resolution of a Position Error Signal (PES) in a disk drive servo is increased by synchronously dithering the analog PES while sampling it with an Analog-to-Digital Converter (ADC)....
6498694 Servo error integration in read-channel equalization  
A method and system for servo error integration in read-channel equalization are described. In the present invention servo error is integrated into an equalizer. Also described in the present...
6498693 Method and system for MR offset calibration  
Method and system aspects for calibrating an MR offset in an MR head are presented. A method aspect includes identifying an occurrence of a calibration condition to initiate an MR offset check, and...
Matches 151 - 200 out of 548 < 1 2 3 4 5 6 7 8 9 10 11 >