Abstract: For each seek command of a plurality of seek commands of a hard disk drive, a correction value is determined that adjusts an access time of the seek command. The correction value includes a scaling factor that adjusts an energy variable. The scaling factor is based on a power target of the hard disk drive, and the energy variable may represent an energy used in the seek command as a time value. The seek commands are sorted in a command queue by the adjusted access times. The seek commands are executed by a controller of the hard disk drive based on the sorting within the command queue.

Abstract: For each seek command of a plurality of seek commands of a hard disk drive, a correction value is determined that adjusts an access time of the seek command. The correction value includes a scaling factor that adjusts an energy variable. The scaling factor is based on a power target of the hard disk drive, and the energy variable may represent an energy used in the seek command as a time value. The seek commands are sorted in a command queue by the adjusted access times. The seek commands are executed by a controller of the hard disk drive based on the sorting within the command queue.

Abstract: Embodiments described herein are operable in a computing system. The computing system receives first and second commands (e.g., I/O commands). The computing system determines that the first command has a higher priority than the second I/O command, and queues the second command for servicing at a later time. The computing system services the first command, and services the second command after a timeout period based on performance degradation limit that decreases command processing performance of the computing system, overrides the timeout period, and increases a probability of executing the second command.

Abstract: Systems and methods are disclosed for probabilistic aging command sorting, including adjusting an execution order for a command based on a probability of the command reaching a time out threshold. The system may determine a probability of a command timing out using a lookup table for a base queue depth, modified by a scalar value obtained from a queue depth adjustment lookup table using the actual queue depth as an index. In this manner, an accurate probability of a command timing out for a given queue depth can be determine without significant computational overhead.

Abstract: Embodiments described herein are operable in a computing system. The computing system receives first and second commands (e.g., I/O commands). The computing system determines that the first command has a higher priority than the second I/O command, and queues the second command for servicing at a later time. The computing system services the first command, and services the second command after a timeout period based on performance degradation limit that decreases command processing performance of the computing system, overrides the timeout period, and increases a probability of executing the second command.

Abstract: Bias force changes in a disk drive, including transient bias changes, are predicted and/or estimated. Bias compensation or change in bias compensation is calculated based on drive operating parameters such as seek length. Calculation can correspond to a modeled relationship of bias forces to seek length. Preferably, bias compensation calculation is adaptive and calculation parameters can be updated during normal read/write use of the disk drive.

Abstract: Controlling seeking of a transducer includes accelerating the transducer to a seek velocity, generating a linearized switching curve defining a position and velocity of the transducer at which deceleration should begin, and controlling the velocity of the transducer in response to the current position and seek velocity of the transducer relative to the linearized switching curve. The linearized switching curve has a slope and an offset that are determined in response to the seek velocity and a current position of the transducer relative to a nonlinear switching curve.

Abstract: Methods of controlling a transducer that is adjacent to a rotatable data storage disk in a disk drive are disclosed, the disk drive having an actuator configured to position the transducer, a rotational acceleration sensor configured to generate a rotational acceleration signal, a position error sensor configured to generate a position error signal, and a controller configured to control the actuator to move the transducer to a target track during a seek operation. The methods include dynamically adjusting a gain factor in response to the position error signal and the acceleration signal during a settle period following the seek operation, multiplying the rotational acceleration signal by the gain factor to generate an adjusted rotational acceleration signal, and adding the adjusted acceleration signal to the position error signal to generate an adjusted position error signal, and moving the transducer in response to the adjusted position error signal.

Abstract: Methods of controlling seeking of a transducer that is adjacent to a rotatable disk in a disk drive include determining an expected seek time associated with moving the transducer from an initial track to a target track on the disk. An expected rotational latency time is determined which is associated with rotating the disk to move an addressed data block on the target track adjacent to the transducer after the transducer would be expected to arrive at the target track. A scaled velocity limit is determined which is based on the expected seek time and the expected rotational latency time. While seeking the transducer from the initial track to the target track, the radial velocity of the transducer relative to the disk is regulated in response to the scaled velocity limit. Related apparatus for controlling seeking of a transducer are also described.

Abstract: Methods of filtering a position error signal (PES) indicative of a position of a transducer of a disk drive include obtaining sample position data for the transducer, eliminating selected data of the sample position data to provide a subset of the sample position data, obtaining a plurality of sets of preliminary filter coefficients based on the subset of the sample position data, obtaining a final set of filter coefficients from the plurality of sets of preliminary filter coefficients, and filtering a position error signal using the final set of filter coefficients. Corresponding disk drives are also disclosed.

Abstract: Methods of controlling seeking of a transducer that is adjacent to a rotatable disk in a disk drive include determining a seek time associated with moving the transducer from an initial track on the rotatable disk to a target track on the rotatable disk, detecting a temperature associated with the disk drive, and determining if the detected temperature exceeds a temperature threshold. The methods may further include increasing the seek time to provide an increased seek time in response to the detected temperature exceeding the temperature threshold, generating a current command based on the increased seek time, and seeking the transducer from the initial track to the target track on the disk based on the current command. An apparatus configured to control the seeking of a transducer is also disclosed.

Abstract: Controlling seeking of a transducer includes accelerating the transducer to a seek velocity, generating a linearized switching curve defining a position and velocity of the transducer at which deceleration should begin, and controlling the velocity of the transducer in response to the current position and seek velocity of the transducer relative to the linearized switching curve. The linearized switching curve has a slope and an offset that are determined in response to the seek velocity and a current position of the transducer relative to a nonlinear switching curve.

Abstract: Methods of controlling an I/O operation of a disk drive include determining a temperature associated with the disk drive, comparing the determined temperature to a temperature threshold, setting a duty cycle limit for the I/O operation in response to the determined temperature exceeding the temperature threshold, and performing the I/O operation subject to the duty cycle limit. The I/O operation may include a data write and/or a data read operation. Disk drives configured to control I/O operations based on temperatures are also disclosed.

Abstract: Methods of controlling seeking of a transducer that is adjacent to a rotatable disk in a disk drive include determining an expected seek time associated with moving the transducer from an initial track to a target track on the disk. An expected rotational latency time is determined which is associated with rotating the disk to move an addressed data block on the target track adjacent to the transducer after the transducer would be expected to arrive at the target track. A scaled velocity limit is determined which is based on the expected seek time and the expected rotational latency time. While seeking the transducer from the initial track to the target track, the radial velocity of the transducer relative to the disk is regulated in response to the scaled velocity limit. Related apparatus for controlling seeking of a transducer are also described.

Abstract: Methods of filtering a position error signal (PES) indicative of a position of a transducer of a disk drive include obtaining sample position data for the transducer, eliminating selected data of the sample position data to provide a subset of the sample position data, obtaining a plurality of sets of preliminary filter coefficients based on the subset of the sample position data, obtaining a final set of filter coefficients from the plurality of sets of preliminary filter coefficients, and filtering a position error signal using the final set of filter coefficients.

Abstract: A disk drive includes a rotatable data storage disk, a transducer, an actuator, and a controller. The transducer is configured to read and write data on the disk. The actuator is configured to position the transducer relative to defined portions of the disk. The controller is configured to write a predetermined magnetic polarity pattern on a buffer portion of the disk to erase data thereon. The controller also determines whether the disk drive has reached a threshold operating temperature, and to selectively direct data from a host device, which is addressed for an associated original block address on the disk, to be written to the buffer portion of the disk when the disk drive has not reached the threshold operating temperature. The controller later copies the data from the buffer portion of the disk to the original block address on the disk and then erases the data from the buffer portion of the disk.

Abstract: A transducer is controlled during seeking based on an acceleration-phase state error. While seeking, the transducer is moved from an initial track to a target track on the disk based on a current command. At least one transducer state relative to the disk is estimated while seeking. At least one transducer state relative to the disk is measured while seeking. An acceleration-phase state error is determined that is indicative of an error between the estimated at least one transducer state and the measured at least one transducer state as the transducer is accelerated toward the target track during the seeking. The current command is generated based on the acceleration-phase state error.

Abstract: A transducer is moved in a seek operation from an initial track to a target track on a disk based on a current command. The current command is regulated based on a location of the transducer and a location of an addressed data block on the disk. The current command may be regulated so that the transducer settles on the target track a predetermined time before the addressed data block reaches the transducer.

Abstract: A method is provided for radially moving a transducer over a storage surface of a rotating data disk including multiple concentric data tracks, for reducing noise generated during a seek operation from a starting track to a destination track on the disk. The transducer is radially moveable relative to said data tracks by an actuator in proportion to an input signal to the actuator, wherein the transducer is initially accelerated away from the starting track to a radial transition location between the starting track and the destination track, and then decelerated toward the destination track from the transition location.

Abstract: The invention includes systems and methods for controlling the position of a device. In one aspect, the invention is a method comprising the steps of providing a device, the device having a position, a velocity, and an acceleration; providing a control signal, the position of the device being responsive to the control signal; and varying the control signal, as the device approaches a desired location, according to a nonlinear function of the position, the velocity, and the acceleration wherein the velocity and the acceleration converge on zero as the device approaches the desired position. A number of alternative nonlinear functions may be used. In another aspect, the invention is an apparatus that controls the position of a device according to the nonlinear function described above.