Modal analysis and tilt drop-test of 1 inch seagate hard disk drive using laser doppler vibrometer

• Main Author: Tan, Berwyn Guanyong.
• Other Authors: Shu Dong Wei
• Format: Final Year Project
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Manufacturing; DRNTU::Engineering::Mechanical engineering::Mechanics and dynamics
• Online Access: http://hdl.handle.net/10356/16111
• Institution: Nanyang Technological University

Hard disk drives are no longer confined to the desktop PC, they are utilized in many portable devices such as hand held gaming devices and laptops. Such disk drives are becoming increasingly smaller in size and are prone to being dropped and mishandled, shortening product lifespan and leading to product failure. One way to improve the resilience of hard disk drives is to study their modal properties and response to shock. The 1 inch Seagate hard disk drive is analyzed in this report. Modal analysis of the key components of the disk drive, namely the disk platter and its actuator arm, is conducted. The hard disk drive is subjected to base excitation by an electromagnetic shaker. Laser doppler vibrometer is used to measure the vibrations of the components. Next, tilt drop test will be conducted. The hard disk drive will be dropped from three different angles to observe how the actuator arm responses to the drop as well as the magnitude of head slap. The laser doppler vibrometer will also be used to read the displacement and velocity of the read/write head. Background information of modal analysis and tilt drop test is covered. Literature review of other methods used to study hard disk drives is also included. The full procedure for conducting the experiments, from set-up, methodology to experimental procedure is listed in detail. Conclusions from the results are derived empirically. The mode shapes and the dominant mode of the disk drive is found. The shock response of the disk drive when subjected to tilt drop is also analyzed. Future work on the drives is also suggested, such as methods to improve the accuracy of readings and methods to overcome the limitations in the experiments.