Check this out…in a whitepaper to be released, Seagate goes into detail to explain what AcuTrac technology really means for desktop storage.
In the upcoming whitepaper, Seagate explains that in addition to areal density (how much data can be written to the disk surface), a second factor influencing storage capacities is track density, commonly measured by tracks per inch (TPI). Hard drives store data in concentric circles (tracks) on the hard drive’s platters; the more tightly these tracks are packed together, the more TPI and disk capacity grow. Increases in TPI have proven to be a key opportunity for the next generation of capacity improvements. AcuTrac is a feature found in the new Barracuda line of desktop hard drives and enables significant increases in TPI. The result: a reliable combination of enterprise-level capacity, speed and performance for the everyday consumer.
The TPI for the new Barracuda line of drives is 340,000 versus 250,000 for the previous generation, a 36% increase. At 340,000 tracks per inch on a 3.5-inch hard drive, that means that each track is only 75 nanometers wide. To put that into perspective, the period (.) at the end of this sentence is 1,000,000 nanometers wide.
When dealing in measures of nanometers, increased pressure is placed on the hard drive heads to accurately read and write data to the disk. Seagate engineers were faced with designing a mechanism to accommodate a drive spinning at 7200 RPM. At such speeds, the read-write head itself is traveling over the disk at speeds of around 80 miles per hour – effectively hurricane force winds. What Seagate engineers designed with AcuTrac technology is a read-write head arm assembly with a 2nd actuator closer to the read-write head enabling TPI improvement by directing the head more accurately to individual tracks, even at the nanometer scale.
Visually, Jason Won, senior director of servo production and corporate servo platform lead at Seagate Technology, paints a pretty cool picture: “In 7200-RPM drives that don’t utilize AcuTrac technology, positioning the head is like trying to ring a doorbell with a ten-foot stick in 80mph winds; with AcuTrac technology, the control mechanism is 80% closer to the head, so the ten-foot stick becomes a two-foot stick. The stick also becomes much more rigid and more easily controlled for better tracking accuracy.”
This new whitepaper will be available on the Barracuda page on Seagate’s website in the coming weeks. I highly suggest you check it out. It’s a great read.