KKU Engineering Journal (Sep 2014)
Equipment to detect bad isolator in hard disk drive testing process
Abstract
With increasing data capacity of hard disk drive (HDD) today, the testing time of a hard disk drive becames longer. It takes approximately 25 - 30 hours. Vibrations during HDD testing process significantly contribute to testing errors. Isolator and pocket slot were used to reduce the vibration. The physical property of isolators was charged, that led to the results of HDD testing. Because of the error, the testing process needs to be redone. As a result, the testing time is extended. This research developed a system to detect isolator function using “Ariduino Due” microcontroller along with “Micro-electromechanical System – MEMS” accelerator sensor. For the precise analysis, the statistical method called t test was used to group isolators by their functioning conditions. It was found that, the measured vibration amplitude in any direction canbe used as the criteria for identifying the isolator conditions. This detective system can determine the bad isolator at early stage before the exceeding vibration will affect the testing process.