Inventors:
Duong Hong Nguyen - Broomfield CO, US
Tan Chin Kiong - Singapore, SG
Richard LeSage - Longmont CO, US
Lee Teng Boon - Singapore, SG
Assignee:
Seagate Technology LLC - Scotts Valley CA
International Classification:
G11B 27/36, G11B 21/02
Abstract:
Detection of head disk interference is provided by monitoring a hard disk drive characteristic related to disk rotation rate. A number of characteristics can indicate HDI. These include the magnitude of decreases in rotation rate, changes in the time-derivative (time-rates of change) of rotation rate or other changes in time-profiles of rotation rate, changes in spin motor current, differences between maximum and minimum values of spin motor current, changes in the time-derivative (time-rates of change) of spin motor current or other changes in time-profiles of spin motor current or combinations or indicators thereof. These approaches to detecting HDI provide several potential advantages. Detection of HDI can be achieved relatively early in a test or other procedure, can be performed relatively rapidly, can distinguish HDI from at least some other anomalies and can indicate the location and/or magnitude of HDI occurrences.