Seagate Technology Incorporated

Josiah Natan Wernow

Evgeny R Kharisov

Mark A Gaertner

Raye Abdoulie Sosseh

Kenneth A Haapala

Brian Thomas Edgar

John Christopher Morris

Randall D Hampshire

Christopher L Hill

Gary Ernest Hillukka

Paul Michael Wiggins

Vidur Parkash

Colin Graham Presly

Evgeny Kharlsov

A method includes generating a first feedforward signal based, at least in part, on a sensor signal. The method further includes generating a second feedforward signal based, at least in part, on a feedforward seek table. A control signal is modified based, at least in part, on the first feedforward signal and the second feedforward signal. A position of an actuator is controlled in response to the modified control signal.

Seek-induced vibration compensation

A data storage device includes at least one data storage medium having a plurality of tracks. The data storage device also includes at least one actuator that supports at least one head that is configured to interact with different tracks of the plurality of tracks on the at least one data storage medium to service commands from a host. The data storage device further includes a seek control circuit communicatively coupled to the at least one actuator. The seek control circuit is configured to store the commands from the host in at least one queue for execution by the at least one actuator. The seek control module is also configured to adjust power provided to the at least one actuator for seek operations to the different tracks of the plurality of tracks based on command age-related measurements of the commands from the host.

Power latency control in data storage devices

Illustrative systems and methods disclosed herein may change or modify a seek during mid-seek for various reasons and may set seek speeds for various seeks to less than the maximum possible seek speed to, for example, facilitate seek target change or modifications mid-seek. For instance, the seek speeds for lower priority commands or commands at risk for deprioritization may be set to speeds less than the maximum possible seek speed.

Modifying seek operations mid-seek

A method includes monitoring an amount of power of a power supply being used by a voice-coil motor (VMC) during a seek operation, detecting that the amount of power has crossed a threshold during the seek operation, and modifying a subsequent seek operation in response to detecting that the amount of power has crossed the threshold.

Voice coil motor saturation detection

HDDs including multiple heads driven by separate actuator spindles can read from or write to one or more platters simultaneously. Simultaneous active heads can be used to increase data rate or for other purposes. The multiple independently-actuated heads can access the same platter or different platters and may be moved across an associated platter surface in a number of different ways. However, multiple independently operating actuators may lead to mechanical coupling between the actuators. For example, as certain resonant frequencies, the movement of one actuator arm may cause unacceptable movement of another actuator arm within the HDD. This mechanical coupling can have detrimental effects on the HDD. The disclosed coupling observer and disable systems detect and mitigate detrimental effects of mechanical coupling between the independently operated actuators.

Magnetic disk device having coupling observers for reducing coupling issues between independently running multi-actuators

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.

Method and apparatus that modifies seek parameter to remediate cross-actuator interference

Method and apparatus that modifies seeks to remediate inter-actuator coupling in a storage drive

In a disk drive apparatus, a first time period is determined, during which a first head driven by a first actuator will be performing a first disk access operation. A second time period is determined, during which a second head driven by a second actuator will be performing a second disk access operation. The first and second actuators are independently movable such that the first and second disk access operations are capable of being performed in parallel. If it is determined that the second disk access operation will impact servo control of the first disk access operation, at least one of the first and second disk access operations is changed to reduce the impact to the servo control of the first disk access operation.

Changing disk access operations to reduce servo control impact in a multiple actuator drive

An apparatus includes a first controller, a second controller, and a coupling compensator. The first controller is configured to generate a first voice coil motor (VCM) control signal in response to a first position error signal. The second controller is configured to generate a second VCM control signal in response to a second position error signal. The coupling compensator is configured to generate a first feedforward correction signal in response to the first VCM control signal. The first feedforward correction signal modifies the second VCM control signal to generate a modified second VCM control signal.

Feedforward compensation for multi-actuator hard drives

The disclosure is related to an apparatus and methods of suppressing seek repeatable runout. In a particular embodiment, a servo loop is disclosed. The servo loop includes a seek signal generation component that generates a seek trajectory acceleration signal. The servo loop also includes a STRRO suppression component that is coupled to the seek signal generation component. The STRRO suppression component injects STRRO suppression signals into the seek trajectory acceleration signal and outputs an STRRO suppressed seek trajectory acceleration signal.

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Saint Paul, MN, United States of America

Josiah Natan Wernow