The invention operates two control paths. The micro-actuator control stimulates
the micro-actuator. The voice coil motor control path includes the voice coil motor
control generating a voice coil control signal, notch filtered to remove at least
one significant excitation resonance for a notch filtered voice coil control signal.
Amplifying the notch filtered voice coil control signal by a tuning gain stimulates
the voice coil motor.
A decoupling feedback filter uses the micro-actuator control signal to create
a
decoupling feedback signal used to decouple the two control paths. A track following
command, with PES removed, directs the micro-actuator control. The voice coil motor
control is directed by the track following command, with both PES and decoupling
feedback signal removed.
Preferably, the servo-controller digitally supports the elements of the
invention. Implementing the method may preferably include the servo-controller
program system residing in an accessibly coupled memory.
The invention includes optimizing an implementation within the hard disk drive.
The optimization may be part of the manufacturing process for the hard disk drive.
The invention includes the hard disk drive as the product of that manufacturing process.