Method for resonance identification in hard disk drives

A hard disk drive, comprising:

• a disk;
• a spindle motor that rotates said disk;
• a head coupled to said disk;
• a notch filter coupled to said head;
• an actuator arm coupled to said head;
• a voice coil motor coupled to said actuator arm;
• and,
• a controller coupled to said head and said notch filter;
• a memory that contains a program which causes in an idle mode said controller to induce a seek operation of said head, processes a position error signal generated during a settling time, determines a first resonant frequency of said position error signal and redefines said notch filter with said resonant frequency.

A hard disk drive, comprising:

• a disk;
• a spindle motor that rotates said disk;
• a head coupled to said disk;
• a notch filter coupled to said head;
• an actuator arm coupled to said head;
• a voice coil motor coupled to said actuator arm;
• and,
• controller means for in an idle mode inducing a seek operation of said head, processing a position error signal generated during a settling time, determining a resonant frequency of said position error signal and redefining said notch filter with said resonant frequency.

A method for redefining a notch filter of a hard disk drive, comprising:

• inducing a seek operation of a head in an idle mode;
• processing a position error signal during a settling time;
• determining a resonant frequency of the position error signal;
• and,
• redefining a notch filter with the resonant frequency.