A victim feedforward signal 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, where the victim feedforward signal is configured to compensate for disturbances to a victim head caused by assertion of the aggressor VCM control signal. Each aggressor VCM control signal is asserted at a specific time by the aggressor actuator, for example in response to the aggressor head passing over a first servo wedge. A feedforward signal that compensates for the effect of the aggressor VCM control signal is then determined based on the aggressor VCM control signal, stored, and asserted via the victim microactuator at a predetermined time relative to when the aggressor VCM control signal is asserted.

According to one embodiment, a magnetic disk device includes a first head which writes and reads to the first disk, a second head which writes data and reads data to the second disk, a first actuator including the first head, a second actuator including the second head, and a controller which performs a first reordering process for a command scored in a first queue corresponding to the first actuator and performs a second reordering process for a command stored in a second queue corresponding to the second actuator, wherein the controller selects a first command to be executed next by the first actuator based on current and future operating states of the second actuator, and executes the first command.

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 connected to a distal end of a first actuator arm, a second head connected to a distal end of second first actuator arm, a first coupler configured to couple the first actuator arm to an actuator, and a second coupler configured to couple the second actuator arm to the actuator. Access commands stored in a command queue are sorted into an execution order based on a selective coupling of the first and second actuator arms to the actuator. At least one of the access commands is executed based on the execution order in order to access at least one of a first and second disk surfaces using at least one of the first and second heads.

A data storage device is disclosed comprising an actuator configured to actuate a head over a disk surface, and a vibration sensor configured to generate a vibration signal (VS). Control circuitry comprising a servo control system having a torque rejection curve (TRC) configured to control the actuator is configured to measure a position error signal (PES) of the head, and measure the VS output by the vibration sensor. A feed-forward compensator is configured based on PES/VS/TRC. While seeking the head across the disk surface, the VS is processed using the feed-forward compensator to generate a feed-forward compensation during a settle interval of the seek, and the actuator is controlled using the feed-forward compensation during the settle interval.

A data storage device is disclosed comprising a first head connected to a distal end of a first actuator arm, a second head connected to a distal end of second first actuator arm, a first coupler configured to couple the first actuator arm to an actuator, and a second coupler configured to couple the second actuator arm to the actuator. Access commands stored in a command queue are sorted into an execution order based on a selective coupling of the first and second actuator arms to the actuator. At least one of the access commands is executed based on the execution order in order to access at least one of a first and second disk surfaces using at least one of the first and second heads.

A data storage device includes a first data storage surface and a second data storage below the first data storage surface. The data storage device also includes a first micro-actuator coupled to a first arm that supports a first head over the first data storage surface, and a second micro-actuator coupled to a second arm that supports a second head over the second data storage surface. The data storage device further includes a coarse actuator, to which the first and second arms are coupled, that positions the first head and the second head between corresponding first and second tracks on the respective first and second data storage surfaces. Micro-actuator drive circuitry finely positions the first head over the first track and the second head over the second track by concurrently driving the first micro-actuator and the second micro-actuator in opposite directions.

A data storage device is disclosed comprising a coarse actuator configured to actuate a first head over a first disk surface and a second head over a second disk surface. A first fine actuator is configured to actuate the first head over the first disk surface, and a second fine actuator is configured to actuate the second head over the second disk surface. A first bias signal is calibrated for the first fine actuator, and a second bias signal is calibrated for the second fine actuator. The first fine actuator is controlled based on the first bias signal and the second fine actuator is controlled based on the second bias signal in order to concurrently access the first disk surface and the second disk surface.