Apparatus and method for compensating for environmental effects on media

An apparatus for positioning a read head for reading data from a medium, comprising:

• a controller;
• and
• an array of servo readers coupled to the controller and positioned at a non-zero azimuth angle relative to the medium, wherein the array of servo readers generate position error signals from data in servo tracks on the medium, and wherein the position error signals are used by the controller to update the azimuth angle of the array of servo readers, wherein the position error signals include a directional component identifying whether a servo reader is closer to a center of the medium than the center of a servo track.

A method of positioning a read head for reading data from a medium, comprising:

• determining a positional error;
• and
• positioning an array of servo readers at a non-zero azimuth angle relative to the medium based on the determined positional error, wherein determining a positional error includes generating position error signals from reading data in servo tracks on the medium using the array of servo readers, wherein determining a positional error further includes generating at least one average position error signal based on the position error signals, wherein the at least one average position error signal is used along with a reference signal to generate an error bias signal, wherein positioning the array of servo readers includes generating a control signal based on the error bias signal and outputting the control signal to at least one actuator, wherein the at least one actuator updates a position of the array of servo readers based on the control signal, and wherein the position of the array of servo readers is updated by updating a non-zero azimuth angle position of the array of servo readers.

A method of positioning a read head for reading data from a medium, comprising:

• determining a positional error;
• and
• positioning an array of servo readers at a non-zero azimuth angle relative to the medium based on the determined positional error, wherein determining a positional error includes generating position error signals from reading data in servo tracks on the medium using the array of servo readers, wherein the position error signals include a directional component identifying whether a servo reader is closer to a center of the medium than the center of a servo track.

A computer program product, in a computer readable medium, for positioning a read head for reading data from a medium, comprising:

• first instructions for determining a positional error;
• and
• second instructions for positioning an array of servo readers at a non-zero azimuth angle relative to the medium based on the determined positional error, wherein the first instructions include instructions for generating position error signals from reading data in servo tracks on the medium using the array of servo readers, wherein the first instructions further include instructions for generating at least one average position error signal based on the position error signals, wherein the first instructions further include instructions for using the at least one average position error signal along with a reference signal to generate an error bias signal, wherein the second instructions include instructions for generating a control signal based on the error bias signal and outputting the control signal to at least one actuator, wherein the at least one actuator updates a position of the array of servo readers based on the control signal, and wherein the position of the array of servo readers is updated by updating a non-zero azimuth angle position of the array of servo readers.

A computer program product, in a computer readable medium, for positioning a read head for reading data from a medium, comprising:

• first instructions for determining a positional error;
• and
• second instructions for positioning an array of servo readers at a non-zero azimuth angle relative to the medium based on the determined positional error, wherein the array of servo readers is partitioned into an upper portion of servo readers and a lower portion of servo readers and wherein the upper portion of servo readers generate a first set of position error signals and the lower portion of servo readers generate a second set of position error signals, and wherein the first instructions further comprise instructions for averaging the first set of position error signals to generate an upper average position error signal and instructions for averaging the second set of position error signals to generate a lower average position error signal, and wherein the first instructions further include instructions for combining the upper average position error signal, the lower average position error signal and a reference signal to generate an error bias signal.