A magnetic recording head positioning assembly includes a coarse travel carriage secured to and spaced away from each of a front end assembly and head assembly via sandwiched fine guiding flexures and isolation flexures. The fine guiding flexures permit relative movement between the coarse travel carriage and head assembly. The isolation flexures permit relative movement between the coarse travel carriage and front end assembly. The fine guiding and isolation flexures thus isolate the coarse travel carriage from the front end assembly and head assembly. The assembly further includes dampers sandwiched between the coarse travel carriage and isolation flexures to limit movement of the isolation flexures.

An actuator assembly for crosstalk reduction in hard disk drives (HDDs) is provided. The actuator assembly comprises a base plate; a pivot; a voice coil motor (VCM) with an upper yoke and a lower yoke; and a cut-out insert having a predetermined stiffness and predetermined magnetic properties, wherein the cut-out insert corresponds to a cut-out recess of the base plate, and wherein the lower yoke of the VCM and the pivot are coupled to the cut-out insert.

A method for writing repeatable run-out data, representing a recurring contribution to position error, to a rotating constant-density magnetic storage medium, includes repeating, for each respective track at a respective radius of the constant-density magnetic storage medium, (1) determining a respective track pattern frequency based on track location and desired data density, (2) locating a position in a respective servo wedge on the respective track based on servo sync mark detection, (3) writing the repeatable run-out data to the respective servo wedge at a time delay, from the location of the position in the respective servo wedge, that is inversely proportional to the respective radius, to achieve a predetermined offset, and (4) repeating the determining, the locating and the writing for each servo wedge on the respective track of the constant-density magnetic storage medium.

A data storage device is disclosed comprising a first disk comprising first servo sectors A.sub.0-A.sub.N distributed around a circumference of the first disk, and a second disk comprising second servo sectors B.sub.0-B.sub.N distributed around a circumference of the second disk, wherein the second servo sectors B.sub.0-B.sub.N are offset circumferentially from the first servo sectors A.sub.0-A.sub.N. While the first and second disks are rotating second servo information is transmitted from a second servo channel to a first servo channel. One of the first servo sectors Ai is read to generate first servo information, and a first command value is generated based on the first servo information and the second servo information, wherein a first actuator is controlled based on the first command value.

A data storage device is disclosed comprising a head actuated over a disk, and a two-dimensional (2D) equalizer comprising a plurality of coefficients. A plurality of stored coefficients are accessed based on a first off-track offset of the head in order to first initialize the coefficients of the 2D equalizer, and then the coefficients of the 2D equalizer are first adapted based at least on a first read signal to generate first adapted coefficients. The plurality of stored coefficients are accessed based on a second off-track offset of the head in order to second initialize the coefficients of the 2D equalizer, and then the coefficients of the 2D equalizer are second adapted based at least on the first read signal to generate second adapted coefficients.

According to one embodiment, a first storage area and a second storage area in which a plurality of tracks are set are provided in a radial direction of a magnetic disk. A plurality of post codes corresponding to the second storage area is stored in the first storage area. A controller controls first processing of reading a plurality of post codes from the first storage area and writing the plurality of read post codes in servo area of the second storage area. In the first processing, the controller controls both second processing and third processing in a state where a write head is located on a first track. The second processing is processing of writing a post code among the plurality of read post codes in a servo area. The third processing is processing of writing user data in a data area or reading user data from a data area.

A microactuator for a dual stage actuated suspension for a hard disk drive is constructed as a longitudinal stack of piezoelectric (PZT) elements acting in the d33 mode, expanding or contracting longitudinally when an electric field is applied across them in the longitudinal direction. The microactuator has interlaced electrode fingers that separate and define the individual PZT elements, and apply the electric field. A stiff constraint layer having a high Young's modulus is affixed to the microactuator on the side opposite the suspension to which the microactuator is bonded. The constraint layer may be a layer of substantially inactive PZT material that is formed integrally with the PZT elements but without electrodes in the inactive PZT layer. The presence of the stiff constraint layer increases the effective stroke length of the microactuator.

A data storage device may be destroyed by suspending a transducing head above a data storage medium prior to inducing contact of the transducing head with a first layer of the data storage medium in response to a signal from a controller. Deflection of the transducing head can then be increased to penetrate to a destroy depth in a second layer of the data storage medium that is maintained while the data storage medium spins. The controller may then issue at least one data read command to access data from the data storage medium and when a data read error is received, the data storage medium and transducing head can be verified as destroyed and incapable of accessing data previously written to the data storage medium.

A data storage device is disclosed comprising a head actuated over a disk, and a sensor configured to generate a sensor signal representing at least one of a shock and a thermal popping affecting the data storage device. The sensor signal is first filtered based on a first frequency range corresponding to the shock to generate a shock signal, and second filtered based on a second frequency range corresponding to the thermal popping to generate a pop signal, wherein the second frequency range is different from the first frequency range. The shock signal and the pop signal are individually processed, for example, to log a disturbance event, to abort a write operation, or to generate a feed-forward servo compensation signal.

A method is disclosed for positioning a transducer over a magnetic recording medium having a plurality of tracks. The method includes positioning the transducer over a first track using a voice coil motor (VCM) and a microactuator. The method further includes applying a feedforward voltage profile to the microactuator to position the transducer over a second track.