Patent ID: 6751043
Filing Date: 2004-06-15
Classification: G11B

Abstract:
A method for controlling the data track seeking and following of a head in a data recording disk file of the type having a disk with servo information thereon defining data track centerlines, a head for reading samples of the servo information during rotation of the disk, an actuator connected to the head and responsive to an input signal for positioning the head to the centerline of a target track during track seeking and maintaining the head over the centerline of the target track during following, the method comprising the steps of:sensing from the servo information a sampled head position error signal (PES) representative of the position of the head relative to the centerline of the nearest track; estimating for each PES sample an absolute head position relative to a fixed reference; estimating for each PES sample a head velocity; estimating for each PES sample an actuator current; estimating for each PES sample a bias force indicative of the equivalent actuator input signal required to compensate bias forces acting on the actuator; and calculating for at least each PES sample an actuator voltage control signal as a function of said PES signal, said estimated absolute head position, said estimated head velocity, said estimated actuator current and said estimated bias force.