摘要 |
A head positioning system includes a feedforward operation controller which calculates a basic head position control signal to output to a head displacement providing device based upon the target track the head is to be moved to and the present head position at the time when a head positioning operation begins. Subsequently, a feedback corrected control signal for head positioning is calculated by a feedback operation controller using a detected signal indicating actual head position relative to the record disk. Until the results from the feedback operation controller are available, the basic head position control signal is utilized for the head positioning operation. This basic head position control signal is also used for controlling head positioning whenever an output from the feedback operation controller is not being provided. When outputs from the feedback operation controller are provided, they are added with the basic head position control signal to form a combined position control signal to control head movement.
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