Abstract: A data storage device is disclosed comprising a head actuated over a disk comprising a plurality of data tracks, including consecutive data tracks N?1 and N. A first write to data track N is performed using a first position error signal (PES) representing a position of the head relative to the data tracks. A track squeeze metric is generated for data track N?1 based on at least the first PES of the first write. The track squeeze metric for data track N?1 is accumulated during the first write, and the first write is aborted when the accumulated track squeeze metric for data track N?1 exceeds a first threshold.

Abstract: A method of driving a vibration wave motor enables proper frequency control of an AC voltage applied to the motor according to the rotational speed difference between the actual and target rotational speeds of the motor, even if frequency-rotational speed characteristics are not stored in advance. A target rotational speed of a moving member is set. A ratio of an amount of increase or decrease in a rotational speed of the moving member to an amount of update of a frequency of the AC voltage and a rotational speed difference between the target rotational speed and an actual rotational speed of the moving member are calculated. The amount of update of the frequency is calculated by dividing the calculated rotational speed difference by the calculated ratio. The frequency of the AC voltage is updated by using the calculated amount of update of the frequency.

Abstract: A method of driving a vibration wave motor, which enables proper frequency control of an AC voltage applied to the motor according to the rotational speed difference between the actual and target rotational speeds of the motor, even if frequency-rotational speed characteristics are not stored in advance. A target rotational speed of a moving member is set. A ratio of an amount of increase or decrease in a rotational speed of the moving member to an amount of update of a frequency of the AC voltage and a rotational speed difference between the target rotational speed and an actual rotational speed of the moving member are calculated. The amount of update of the frequency is calculated by dividing the calculated rotational speed difference by the calculated ratio. The frequency of the AC voltage is updated by using the calculated amount of update of the frequency.