Actuator resonance screening in disc drives

A disc drive system having an actuator, comprising:

• (a) a servo controller, the servo controller partitioning a disc into a plurality of servo zones, each of the servo zones having a corresponding servo gain;
• (b) an actuator resonance detector, operatively connected to the actuator and the servo controller, which detects actuator resonance;
• and
• (c) gain control, in response to an actuator resonance in one of the plurality of servo zones detected by the actuator resonance detector, which reduces the corresponding servo gain of the servo zone, in which the actuator resonance was detected, in the servo controller.

A method of reducing actuator resonance in a disc drive, the disc drive including a disc, an actuator positioned adjacent the disc, and a servo controller for controlling the movement of the actuator, comprising steps of:

• (a) partitioning the disc into a plurality of servo zones, each servo zone being associated with a unique region of the disc;
• (b) maintaining a reduced servo gain for at least one servo zone associated with a detected resonance of the actuator as the actuator travels over the region of the disc associated with the at least one servo zone;
• and
• (c) adjusting gain of the servo controller with the reduced servo gain whenever the actuator travels over the region of the disc associated with the at least one servo zone having the detected resonance.