Seek control and settling control taming actuator resonance of HDD

A short-distance seek control and a settling control for HDD have been developed. The short-distance seek control is composed of a feedforward control and a feedback control. The trajectory is designed through an FIR notch filter whose output has little power at resonance frequencies of the actuator. We have applied the new trajectory design to the settling control that is used to connect a long-distance seek with a following control. The servo controller generates feedforward trajectories based on the initial position and initial velocity of the actuator at the beginning of settling control and estimates bias offset.