According to an embodiment, a magnetic disk, a magnetic head, an actuator and a processing unit are provided. The processing unit acquires a feature amount from a position error between a demodulated position and an estimated position of the magnetic head based on a frequency resonance characteristic of the actuator or a frequency characteristic of vibration caused by disturbance of the actuator and, based on the feature amount, sets an on-track determination number used for confirming an on-track state of the magnetic head after seeking.

An apparatus and method for dynamic multiple actuator drive data access are disclosed. A particular embodiment includes: receiving a data transfer request including at least one data package; determining a type of the data transfer request; partitioning the data package into a plurality of data segments, if the data transfer request is a parallel data mode request; assigning one or more actuator drivers and one or more actuator controllers for the data transfer request; initiating a data transfer to or from the data storage medium using one or more of the plurality of actuators corresponding to the one or more assigned actuator controllers; storing or retrieving an individual data package of the data transfer request to or from the data storage medium wherein the entire data package is wholly accessible to a single actuator, if the data transfer request is a random data mode request; and storing or retrieving an individual data segment of the data transfer request to or from the data storage medium wherein the data package is accessible to the plurality of actuators, if the request is a parallel data mode request.

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.

According to one embodiment, a stopper of a disk device, to regulate movement of movable member of a disk device, includes a fixing member to be fixed to a supporter of the disk device, and a cushioning member formed of a rubber and attached to the fixing member. The cushioning member includes a contact surface which contacts the fixing member, a first contact surface which can contact the supporter of the disk device, and a second contact surface which can contact a movable member in the disk device, the first contact surface has a first surface adhesive force based on adhesion of the rubber, and the second contact surface is subjected to a non-adhesive surface treatment and has a second surface adhesive force which is less than the first surface adhesive force.

An actuator pivot assembly for a multi-actuator shared shaft data storage device may include a shared pivot shaft around which a first rotary actuator assembly is coupled, with a first bearing assembly interposed therebetween with a first bearing preload, and around which a second rotary actuator assembly is coupled, with a second bearing assembly interposed therebetween with a second different bearing preload. Furthermore, the first bearing assembly may have a first bearing span and the second bearing assembly may have a second bearing span that is different from the first bearing span. Each of the foregoing bearing features may thereby assist with spacing apart the structural resonance frequencies of the actuator assemblies to inhibit transmission of vibration between the actuators during operation.

A split-shaft pivot assembly for a dual-actuator data storage device may include a first pivot shaft having a threaded stud extending from one end and an attachment flange at the other end, and a second pivot shaft having a threaded bore at one end a structurally equivalent attachment flange at the other end, where the two pivot shafts are attached to each other by threading the stud into the bore. A first bearing assembly may be affixed with a first preload around the first pivot shaft, and a second bearing assembly may be affixed with a second different preload around the second pivot shaft. The pivot assembly may further include an elastomeric damper positioned within an annular groove formed in, and around the threaded stud of, the first pivot shaft. Such features may serve to inhibit and/or damp transmission of vibrational energy among the actuators through the shared split-shaft.

Methods, systems, and apparatuses are described for provisioning storage devices. An example method includes determining a write status of an adjacent track that is adjacent to a target track of a shingled magnetic recording (SMR) disk drive. The method may further include determining an offset for a write head based on the write status of the adjacent track and positioning the write head according to the offset.

A data storage device is disclosed comprising a spindle motor configured to rotate a disk, and a first voice coil motor (VCM) configured to actuate a head over the disk. During at least fifty percent of a seek of the head over the disk, a spindle control signal is generated based on a continuous function of a current flowing through the first VCM, and the spindle control signal is applied to the spindle motor.

A system includes a read/write module and a caching module. The read/write module is configured to access a first portion of a recording surface of a rotating storage device. Data is stored on the first portion of the recording surface of the rotating storage device at a first density. The caching module is configured to cache data on a second portion of the recording surface of the rotating storage device at a second density. The second portion of the recording surface of the rotating storage device is separate from the first portion of the recording surface of the rotating storage device. The second density is less than the first density.

Various aspects are directed to a data storage device comprising one or more disks, an actuator mechanism configured to position a selected head among one or more heads proximate to a corresponding disk surface among the one or more disks, and one or more processing devices. The one or more processing devices are configured to detect repeatable runout (RRO) noise components from a measurement of fly height of the selected head above one or more sectors of a fly height measurement track, and remove the detected RRO noise components from one or more per-sector readback signal measurements.