Publication

Precise Velocity Control of a Hard Disk Drive

2007
Student Projects

Abstract

The ramp technology was integrated in the Hard Disk Drive a couple of years ago, this technology allows a safer parking position for the heads, but also allow the heads to fly closer from the media, increasing the data density. The Load and Unload operations need a precise velocity control of the Voice Coil Motor (VCM) to avoid permanent damage of the heads and the media. This velocity control has, of course, to be achieved without sensors.

Official source

Graph Chat

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.

2007
Student Projects

Abstract

Official source

Related concepts (32)

Hard disk drive

A hard disk drive (HDD), hard disk, hard drive, or fixed disk, is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnetic material. The platters are paired with magnetic heads, usually arranged on a moving actuator arm, which read and write data to the platter surfaces. Data is accessed in a random-access manner, meaning that individual blocks of data can be stored and retrieved in any order.

Hard disk drive performance characteristics

Higher performance in hard disk drives comes from devices which have better performance characteristics. These performance characteristics can be grouped into two categories: access time and data transfer time (or rate). The access time or response time of a rotating drive is a measure of the time it takes before the drive can actually transfer data. The factors that control this time on a rotating drive are mostly related to the mechanical nature of the rotating disks and moving heads.

Hybrid drive

In computing, a hybrid drive (solid state hybrid drive – SSHD) is a logical or physical storage device that combines a faster storage medium such as solid-state drive (SSD) with a higher-capacity hard disk drive (HDD). The intent is adding some of the speed of SSDs to the cost-effective storage capacity of traditional HDDs. The purpose of the SSD in a hybrid drive is to act as a cache for the data stored on the HDD, improving the overall performance by keeping copies of the most frequently used data on the faster SSD drive.

Related publications (5)

Precise Velocity Control of a Hard Disk Drive

Chat with Graph Search

Inside the Solid State Transformers

Casting States of Matter: the construction of thermodynamic 3D-models at the end of the 19th century

Approximate Probabilistic Tree Indexing for Partitionable Data