Operating a hard disk drive is as complex as keeping a superfast car on the road. Read/write heads within the hard disk must process a huge amount of data at high speed. Controlling the motion of the slider housing these heads is crucial: if the slider crashes, it could destroy the hard disk.
The triangular mesh used to model the properties of a hard disk read/write head. The colors represent the pressure profile of the head; red indicates areas of high pressure.
© 2013 A*STAR Data Storage Institute
Researchers at the A*STAR Data Storage Institute (DSI) in Singapore have now developed a computational algorithm for studying the properties of the slider in a hard drive that is faster than existing algorithms1. Instead of taking days to finish, dynamic simulations using the new algorithm take only an hour, notes Wei Hua from the research team. “It greatly improves our simulation and research abilities,” he adds.
A read head typically moves across the disk surface of a hard drive at more than 7,000 revolutions per minute. The flying height of this fast-moving head is as low as 2 nanometers from the surface of the disk, some 50,000 times less than the width of a human hair. Controlling this motion is not easy, notes Hua. “The slider housing the read/write head flies on the fast-rotating hard drive disk, owing to a very thin layer of air. This air bearing pushes the slider upward, while a suspension bearing pushes the slider down toward the disk.”
Thermal effects control the distance of the head to the surface when it is being pushed down. To understand these effects, and other factors that control disk and head movements at high speed, fine-grained computer simulations are necessary.
Hua and co-workers expanded the DSI’s ABSolution air bearing simulation software for faster and more precise modeling. Instead of dividing the hard drive slider into a structured rectangular mesh typically used to aid calculations, the researchers used an unstructured triangular mesh that accurately captures the geometry of the read/write head (see image). Moreover, the algorithm better implements the dynamic effects that occur in drive heads, meaning that overall the code works faster and more efficiently.
This modeling software should prove useful in the future development of drive heads, Hua notes. Modeling the interaction between the slider and the rest of the drive is also important. “Influences such as those from the air suspension and disk effects are now being considered,” he explains. Hua and co-workers will use the improved algorithm to model slider properties that were almost impossible to simulate using the previous versions.
The A*STAR-affiliated researchers contributing to this research are from the Data Storage Institute
Hua, W., Yu, S., Zhou, W. & Myo, K. S. A fast implicit algorithm for time-dependent dynamic simulations of air bearing sliders. Journal of Tribology 134, 031901 (2012).
NASA CubeSat to test miniaturized weather satellite technology
10.11.2017 | NASA/Goddard Space Flight Center
New approach uses light instead of robots to assemble electronic components
08.11.2017 | The Optical Society
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
17.11.2017 | Physics and Astronomy
17.11.2017 | Health and Medicine
17.11.2017 | Studies and Analyses