As storage data density in hard-disk drives (HDDs) increases, precision positioning of HDD heads becomes a more relevant issue to ensure enormous amounts of data to be properly written and read. Since the traditional single-stage voice coil motor cannot satisfy the positioning requirement of high-density tracks per inch HDDs, dual-stage servo systems have been proposed to overcome this matter, by using voice coil motors to coarsely move the HDD head while piezoelectric actuators provide fine and fast positioning. Thus, the aim of this work is to apply topology optimization to design HDD arms, by finding optimal placement of base-plate and piezoelectric material for high precision positioning HDD heads. Topology optimization is a structural optimization technique that combines the finite element method with optimization algorithms, and it uses a rational approximation of material properties to vary the material properties between "void" and "filled" portions. The design problem consists in generating optimized structures that provide maximized displacements, appropriate structural stiffness, and resonance phenomena avoidance. The requirements are achieved by applying formulations to maximize displacement, first resonance frequency, and structural stiffness. The implementation of the algorithm and results that confirm the feasibility of the approach in obtaining improved conceptual designs are presented.
Bibliographical noteFunding Information:
The authors thank Krister Svanberg for providing the GCMMA code to CYK. CYK thanks FAPESP (State of São Paulo Research Foundation, Brazil) for his postdoctoral research scholarship (grant number 2009/18210-6 ). LAMM also thanks FAPESP for his postdoctoral research scholarship (grant number 2009/18210-6 ). PHN and ECNS would like to acknowledge FAPESP for the doctoral fellowship (grant number 06/50640-2 ) and research project (grant number 2011/02387-4 ), respectively, provided to developing this study. ECNS also acknowledges the financial support of the National Council for Scientific and Technological Development (grant number: 304121/2013-4 ).
All Science Journal Classification (ASJC) codes
- Computer Graphics and Computer-Aided Design
- Applied Mathematics