Abstract: To achieve fast positioning of a head by determining an initial value dynamically from state variables of a system at a switching time of control modes. In a recording device having a head, a recording media including a plurality of tracks accessed by the head, and a motor for moving the head, in order to position the head to a target track by switching control modes and outputting a control signal value u(n) to drive the motor in response to an input signal value y(n) representing a difference between a current position of the head and the target track, the gain of a control system having the input and control signal values as state variables is changed only at a mode switching time.

Abstract: To achieve fast positioning of a head by determining an initial value dynamically from state variables of a system at a switching time of control modes. In a recording device having a head, a recording media including a plurality of tracks accessed by the head, and a motor for moving the head, in order to position the head to a target track by switching control modes and outputting a control signal value u(n) to drive the motor in response to an input signal value y(n) representing a difference between a current position of the head and the target track, the gain of a control system having the input and control signal values as state variables is changed only at a mode switching time.