Variable stopwrite threshold using kurtosis
AssigneeInternational Business Machines Corporation
InventorsRandy C. Inch, Kevin B. Judd
Life of this patent
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Abstract
A method according to one embodiment includes measuring a current position error signal, and calculating a statistical derivative using the current position error signal sample. A kurtosis value is calculated using a current position error signal sample or derivative thereof. A threshold value is adjusted using the kurtosis value. The statistical derivative is compared to the threshold value, and writing is enabled when the statistical derivative does not exceed the threshold value. A determination is made whether to enable or disable writing based on a stopwrite threshold when the statistical derivative exceeds the threshold value.
Claims20
A data storage system, comprising:
- a head;
- a drive mechanism for passing a medium over the head;
- a controller electrically coupled to the head;
- logic encoded in or available to the controller for measuring a current position error signal;
- logic encoded in or available to the controller for calculating a statistical derivative using the current position error signal;
- logic encoded in or available to the controller for calculating a kurtosis value using a current position error signal sample or derivative thereof;
- logic encoded in or available to the controller for adjusting a threshold value using the kurtosis value;
- logic encoded in or available to the controller for comparing the statistical derivative to the threshold value;
- logic encoded in or available to the controller for enabling writing when the statistical derivative does not exceed the threshold value;
- and
- logic encoded in or available to the controller for determining whether to enable or disable writing based on a stopwrite threshold when the statistical derivative exceeds the threshold value.
A method, comprising:
- measuring a current position error signal;
- calculating a statistical derivative using the current position error signal;
- calculating a kurtosis value using a current position error signal sample or derivative thereof;
- adjusting a threshold value using the kurtosis value;
- comparing the statistical derivative to the threshold value;
- enabling writing when the statistical derivative does not exceed the threshold value;
- and
- determining whether to enable or disable writing based on a stopwrite threshold when the statistical derivative exceeds the threshold value.
A computer program product, the computer program product comprising a non-transitory computer readable storage medium having computer readable program code embodied therewith, the computer readable program code readable/executable by a controller to:
- measure, by the controller, a current position error signal;
- calculate, by the controller, a statistical derivative using the current position error signal;
- calculate, by the controller, a kurtosis value, using a current position error signal sample or derivative thereof;
- adjust, by the controller, a threshold value using the kurtosis value;
- compare, by the controller, the statistical derivative to the threshold value;
- enable, by the controller, writing when the statistical derivative does not exceed the threshold value;
- and
- determine, by the controller, whether to enable or disable writing based on a stopwrite threshold when the statistical derivative exceeds the threshold value.
Dependencies are inferred from the claim text.