Patent ID: 8958169
Filing Date: 2015-02-17
Classification: G11B

Abstract:
1. A data storage device comprising: a disk comprising a plurality of tracks defined by servo sectors; a head; and a servo controller configured to servo the head over the disk based on an estimated state generated by a state estimator, wherein the servo controller is configured to execute a seek operation to seek the head over the disk and recover from a servo fault during the seek operation by at least: generating an initial state estimate of the head at the beginning of the servo fault; decelerating the head open-loop using a model-based deceleration control in response to the initial state estimate; while decelerating the head, re-qualifying the state estimator before the head reaches zero velocity; and after re-qualifying the state estimator and before the head reaches zero velocity, seeking the head to a target track closed-loop using the state estimator.