Method, medium, and apparatus controlling track seek in a recording and/or reproducing apparatus

An apparatus to control a track seek of a hard disk drive that includes a notch filter for filtering a voice coil motor (VCM) driving current and a VCM driver for driving a voice coil motor corresponding to an output of the notch filter, the apparatus comprising:

• a sinewave trajectory producer to calculate a position y*, a velocity v*, and an acceleration a*, according to acceleration trajectories, in a form of an ideal sinewave corresponding to a track seek distance and a new sinewave having a compensated for gain distortion and phase delay caused by the notch filter and the VCM driver;
• a state estimator to estimate a position y, a velocity v, and an acceleration a with which a transducer is moved over a disk;
• a first adder to subtract the estimated position y from the position y*;
• a position control gain compensator to obtain a position correction value by multiplying a resultant value from the first adder by a predetermined position gain Kp for position correction;
• a second adder to subtract an estimated velocity v(n) from a sum of the position correction value and the velocity v*;
• a velocity control gain compensator to obtain a velocity correction value by multiplying a resultant value from the second adder by a predetermined velocity gain Kv for velocity correction;
• and
• a third adder to subtract an estimated acceleration a(n) from a sum of the velocity correction value and the acceleration a* to obtain a VCM driving current u(n).

A hard disk drive comprising:

• a disk to store data
• a spindle motor to rotate the disk;
• a transducer to write and/or read data to/from the disk;
• a voice coil motor (VCM) driver to drive a voice coil motor to move the transducer over a
• surface of the disk;
• a notch filter to filter a VCM driving current to drive the voice coil motor and to apply the filtered VCM driving current to the VCM driver
• a controller to generate the VCM driving current to move the transducer according to acceleration trajectories in a form of an ideal sinewave corresponding to a track seek distance and a new sinewave having a compensated for gain distortion and phase delay caused by the notch filter and the VCM driver,
• wherein the controller:
• measures a gain distortion and a phase delay caused by the notch filter and the VCM driver with respect to a frequency corresponding to a track seek distance;
• obtains the new sinewave in which the measured gain distortion and measured phase delay are compensated for by from a complex number indicating the measured gain distortion and the measured phase delay with respect to the frequency;
• generates the VCM driving current using an acceleration trajectory in a form of the new sinewave;
• and
• drives a VCM actuator by applying the VCM driving current to the VCM driver through the notch filter.

A comruter readable recording medium comprising computer readable code to implement a method of controlling a track seek of a hard disk drive, which generates a voice coil motor (VCM) driving current using a sinewave acceleration trajectory having a frequency corresponding to a track seek distance, and which applies the VCM driving current through a notch filter to a VCM driver that drives a VCM actuator, the method comprising:

• measuring a gain distortion and a phase delay caused by the notch filter and the VCM driver with respect to the frequency;
• expressing the measured gain distortion and measured phase delay using a complex number;
• obtaining a new sinewave in which the measured gain distortion and measured phase delay are compensated for by using a sinewave of the frequency and the complex number;
• generating the VCM driving current using to acceleration trajectory in a form of the new and
• driving the VCM actuator by applying the VCM driving current to the VCM driver through the notch filter.

A recording and/or reproducing apparatus, comprising:

• a means for obtaining a new sinewave in which a gain distortion and phase delay, of a driver and a filter, are compensated for by using another sinewave and a complex number representing the gain distortion and phase delay;
• a means for generating a driving current using an acceleration trajectory in a form of the new sinewave;
• and
• a means for driving an actuator by applying the driving current to the driver through the filter.

A method of controlling a hard drive, which generates a voice coil motor (VCM) driving current using a sinewave acceleration trajectory having a frequency corresponding to a track seek distance, and which applies the VCM driving current through a notch filter to a VCM driver that drives a VCM actuator, the method comprising:

• obtaining a new sinewave in which gain distortion and phase delay caused by the notch filter and the VCM driver are compensated for by using a sinewave of the frequency and a complex number representing the gain distortion and phase delay;
• generating the VCM driving current using an acceleration trajectory in a form of the new sinewave;
• and
• driving the VCM actuator by applying the VCM driving current to the VCM driver through the notch filter.

A method of controlling a hard drive, which generates a voice coil motor (VCM) driving current using a sinewave acceleration trajectory having a frequency corresponding to a track seek distance, and which applies the VCM driving current through a notch filter to a VCM driver that drives a VCM actuator, the method comprising:

• obtaining a new sinewave in which gain distortion caused by the notch filter and the VCM driver is compensated for by using a sinewave of the frequency and a complex number representing the gain distortion;
• generating the VCM driving current using an acceleration trajectory in a form of the new sinewave;
• and
• driving the VCM actuator by applying the VOM driving current to the VCM driver through the notch filter.

A method of controlling a hard drive, which generates a voice coil motor (VCM) driving current using a sinewave acceleration trajectory having a frequency corresponding to a track seek distance, and which applies the VCM driving current through a notch filter to a VCM driver that drives a VCM actuator, the method comprising:

• obtaining a new sinewave in which phase delay caused by the notch filter and the VCM driver is compensated for by using a sinewave of the frequency and a complex number representing the phase delay;
• generating the VCM driving current using an acceleration trajectory in a form of the new sinewave;
• and
• driving the VCM actuator by applying the VCM driving current to the VCM driver through the notch filter.