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Investigation of HDD Ramp Unloading Processes with an Efficient Scheme

Published online by Cambridge University Press:  03 June 2015

Yan Liu  and
Hejun Du
Yan Liu
Affiliation:
School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
Hejun Du*
Affiliation:
School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
*
*Corresponding author. URL: http://www.ntu.edu.sg/home/mhdu/Email: mhdu@ntu.edu.sg
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Abstract

Ramp load/unload (L/UL) mechanisms are widely used to rest sliders in hard disk drives (HDDs). Loading/unloading a slider swiftly and smoothly is crucial in a HDD design. A novel, efficient simulation scheme is proposed to investigate the behaviors of a head disk interface (HDI) in ramp unloading processes. A dual scale model is enabled by decoupling the nano-meter scale change of an air bearing and the micro- or milli-meter scale deformation of a suspension. A modified Reynolds equation governing the air bearing was solved numerically. The slider design was characterized with performance functions. Three stages in an unloading process were analyzed with a lumped parameter suspension model. Key parameters for the model were estimated with a comprehensive finite element suspension model. Finally, simulation results are presented for a commercial HDI design.

Keywords

65P40Hard disk driverampunloadinghead-disk interfacesuspensionReynolds equationperformance surfaces
Type
Research Article
Information
Advances in Applied Mathematics and Mechanics , Volume 3 , Issue 6 , December 2011 , pp. 716 - 728
Copyright
Copyright © Global-Science Press 2011

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