Abstract:
Hard disk is a major device of computer for archiving data. In general, it consists of main components such as disk platters, read/write heads and control circuit for reading and writing data. While the hard disk is operating, the disk platter spins with high speed and also the reader located on the Actuator arm floats on the disk platter in order to read and write the data. In the meantime, the very quick spinning causes a vibration of the disk which such vibration also causes a vibration of the Actuator arm installed in several levels that depends on hard disks series. The LDV (Laser Doppler Vibrometer) is used to measure such vibration with laser starting from shooting Laser into the Actuator arm located next to the hard disk without the disk platter. At the same time, the Actuator arm is also actuated by Voice Coil. To measure the vibration in vertical line is most preferred at the moment; however, to measure the vibration in horizontal line is also interesting to do due to there is an effect with the vibration of the Actuator arm as same as the vibration in vertical line. And it is quite difficult to measure the vibration in vertical line with an inner arm because of the overlie figure of the Actuator arm, but the vibration measurement in horizontal line is able to fix such problem. Furthermore, the result of measurement such as the nature frequency or mode shape can be used for analysis in the industry of hard disk production in order to avoid some modes that will badly influence with operations. Moreover, the result can be used for developing the design of Actuator arm.