Date of Award
5-2006
Culminating Project Type
Thesis
Department
Mechanical and Manufacturing Engineering
College
College of Science and Engineering
First Advisor
Andrew Bekkala
Second Advisor
Jeongmin Byun
Third Advisor
Roozbeh Vakil
Keywords and Subject Headings
Hard disk, suspension assembly, vibration, storage
Abstract
The vast majority of computers contain hard disk drives (HOD). HDDs are storage devices that contain electromechanical parts and are subjected to environmental and operational vibrations that can hinder performance. The influence of such vibrations can be· minimized either by raising natural frequencies or by application of dampers to minimize the response. A passive damping approach is adopted in this research since it is effective, inexpensive to fabricate and very easy to incorporate.
Through modal analysis of the drive's suspension arm, the natural frequencies and mode shapes were found. The sway mode has been identified as the most detrimental and may be a roadblock to increased future hard drive performance. Experimental and finite element analyses were used to examine the sway mode. The purposes of this thesis are to developed 3-D optimized model and improve the sway performance by using optimized damping layer.
A viscoelastic material is a unique material that has both the elastic and viscous property. A viscoelastic material was used as a damper to reduce sway vibration in the model. Constrained treatments are in some ways more efficient than free layer treatments. A viscoelastic damping layer was applied between the suspension assembly and Mylar. Ross, Kerwin and Ungar's (RKU) equation explains best the three layer beam. Various parameters of the viscoelastic material were chosen that effect the response. To find effect of the damping layer on the amplitude response, several models were run with damping layers at different locations. It was found that a damping layer located at the hinge had highest damping effect in the first sway mode. A 20.95 (dB) reduction of amplitude was obtained when the viscoelastic material was located at the hinge area. The hinge part was chosen for further analysis, where Young's modulus, loss factor and height of the viscoelastic material were varied. It was found that the best damping effect was obtained with a Young's modulus of 2.5xl05 (kPa).
Recommended Citation
Baral, Madan, "Improved Design Method for Hard Disk Suspension Assembly" (2006). Culminating Projects in Mechanical and Manufacturing Engineering. 79.
https://repository.stcloudstate.edu/mme_etds/79
