Motor torque constant variation compensation

• Main Authors: ANDRESS JEFFREY D, LYLE RYAN TODD, WOODS PHILIP R
• Format: Patent
• Language: English
• Published: 18.04.2006
• Subjects: INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; PHYSICS

Method and apparatus for compensating for a decrease in the torque constant of an actuator motor in a data storage device. An actuator supports the head adjacent a data recording surface on which a plurality of tracks are defined. A servo circuit outputs current to the actuator motor to carry out a seek to move the head from an initial track to a destination track in accordance with a velocity profile having a nominal deceleration trajectory along which the head is decelerated to reach the destination track. The servo circuit operates to adjust an initial value of gain to a second value in response to a selected parameter, and scales the nominal deceleration trajectory to a derated deceleration trajectory in relation to the second value of the gain. The derated deceleration trajectory is preferably selected in relation to the difference between the second value of gain and a predetermined threshold.