A data storage device is disclosed comprising at least one head configured to access a magnetic tape. A plurality of access commands are stored in a command queue, and a wear value is generated for each access command in the command queue, wherein the wear value represents a level of wear on the head or magnetic tape associated with executing the access command. An execution order for the access commands is generated based on the wear values, and at least one of the access commands is executed based on the execution order.

ECC is used to for controlling errors in blocks of data by including a measure of redundancy within the data for recovering one or more unreadable portions of the data. A codeword includes at least a message and one or more additional ECC blocks. In the event of an unreadable sector, the ECC is decoded and used to recover the erroneous or missing portion(s) of the message. With disc access parallelism, ECCs can now be distributed across data storage surfaces and/or multiple storage platters. Distribution of ECCs increases the likelihood of recovering data from a head failure or from burst errors on a data storage surface and adds the option to decode parity after only 1/n revolutions.

In a multi-actuator drive, the effect of moving a first actuator (the so-called “aggressor actuator”) in on a second actuator (the so-called “victim actuator”) is reduced or compensated for. A victim feedforward signal for a particular head of the victim actuator is added to a microactuator control signal of the victim actuator in response to a voice-coil motor (VCM) control signal that is applied to the aggressor actuator. The feedforward signal is configured to compensate for disturbances to the victim microactuator caused by VCM commands provided to the aggressor actuator. The feedforward signal is based on a transfer function that models commands added to the victim microactuator, which is coupled to the particular head of the victim actuator, as a function of the aggressor VCM control signal applied to the aggressor actuator.

In a multi-actuator drive, the effect of moving a first actuator (the so-called “aggressor actuator”) in on a second actuator (the so-called “victim actuator”) is reduced or compensated for. A victim feedforward signal for a particular head of the victim actuator is added to a microactuator control signal of the victim actuator in response to a voice-coil motor (VCM) control signal that is applied to the aggressor actuator. The feedforward signal is configured to compensate for disturbances to the victim microactuator caused by VCM commands provided to the aggressor actuator. The feedforward signal is based on a transfer function that models commands added to the victim microactuator, which is coupled to the particular head of the victim actuator, as a function of the aggressor VCM control signal applied to the aggressor actuator.

According to one embodiment, there is provided a hard disk drive including a first recording surface, a second recording surface, a first magnetic head, a first actuator and a second actuator that move the first magnetic head, a second magnetic head, a third actuator and a fourth actuator that move the second magnetic head, a fifth actuator that moves the second actuator and the fourth actuator, a drive circuit that implements at least one of a first mode in which the second actuator and the fourth actuator operate differently from each other or a second mode in which the first and third actuators operate differently from each other, and a controller that controls the drive circuit.

According to one embodiment, a magnetic disk device includes a magnetic disk, a magnetic head, a first actuator that moves the magnetic head to a predetermined position on the magnetic disk, a second actuator that is provided in the first actuator and adjusts a position of the magnetic head, a control unit that controls operations of the first actuator and the second actuator, and a storing unit that stores a coefficient of an approximation polynomial calculated based on an approximation formula for approximating voltage dependency of a gain of the second actuator. When controlling the operation of the second actuator, the control unit calculates the gain amplitude of the second actuator from the approximation polynomial in which the coefficient is used and amplitude of a voltage input to the second actuator.

A data storage device is disclosed wherein an elevator actuator is controlled to move a head along an axial dimension toward a first disk surface of a first disk while processing a proximity signal generated by a proximity sensor. A first actuator position is detected when the actuator arm is proximate the first disk surface of the first disk based on the proximity signal.

According to one embodiment, a magnetic disk device includes a magnetic disk, a magnetic head, a first actuator that moves the magnetic head to a predetermined position on the magnetic disk, a second actuator that is provided in the first actuator and adjusts a position of the magnetic head, a control unit that controls operations of the first actuator and the second actuator, and a storing unit that stores a coefficient of an approximation polynomial calculated based on an approximation formula for approximating voltage dependency of a gain of the second actuator. When controlling the operation of the second actuator, the control unit calculates the gain amplitude of the second actuator from the approximation polynomial in which the coefficient is used and amplitude of a voltage input to the second actuator.

A data storage device is disclosed comprising a first head actuated over the first disk surface, and a second head actuated over a second disk surface. A concurrent access of the first and second disk surface is executed by accessing the first disk surface without accessing the second disk surface during a single access interval, and after the single access interval, concurrently accessing the first and second disk surface during a dual access interval.

An approach to a reduced-head hard disk drive (HDD) involves an elevator platform assembly for moving an actuator assembly, one or more bearing assemblies, and a load/unload ramp along one or more support posts to provide a head slider access to at least two different recording disk media of a disk stack. The HDD may include a piezoelectric actuator locking mechanism integral to one of the bearing assemblies, such that actuation of the actuator either locks or unlocks the locking mechanism relative to a corresponding support post. When unlocked, the elevator platform assembly can be translated along the length of the disk stack via a motor.