Patent ID: 7564641
Filing Date: 2009-07-21
Classification: G11B

Abstract:
1. A controller-characteristic changing apparatus that changes a controller characteristic of a controller that controls positioning of a head that performs at least one of data writing and data reading with respect to a storage medium, the controller-characteristic changing apparatus comprising: an vibration detector that detects whether the head is subjected to external vibration due to an external factor; a first changing unit that, when the vibration detector detects the external vibration while the controller is controlling the positioning of the head according to a positioning-oriented controller characteristic that takes an accuracy of positioning the head into account, changes the positioning-oriented controller characteristic to a vibration-reducing controller characteristic that improves a reduction effect of vibration of a first frequency band; and a second changing unit that, when the vibration detector detects absence of the external vibration while the controller is controlling the positioning of the head according to the vibration-reducing controller characteristic, changes the vibration-reducing controller characteristic to the positioning-oriented controller characteristic, wherein a reduction rate of the vibration of the head for the vibration-reducing controller characteristic is higher than a reduction rate of the vibration of the head for the positioning-oriented controller characteristic in the first frequency band, and the reduction rate of the vibration of the head for vibration-reducing controller characteristic is lower than the reduction rate of the vibration of the head for positioning-oriented controller characteristic in a second frequency band that is higher than the first frequency band.