|2009||WD Caviar Black 2 TB|
|Two stage actuation enables higher track pitch|
Why it's important
A two stage actuator separates the track to track motion into a coarse postioner and a fine positioner thereby lowering the mass of the fine positioniong mechanism which allows higher track pitch and thereby higher areal density.
In 1983 Drivetec shipped a flexible media disk drive using a dual stage stepper/stepper design that read conventional and high tpi FDs (it used a coarse stepper driving a cantilevered beam carrying the second fine stepper positioning the head over the track.).First commercialization in HDDs announced as WD Caviar Black 2 TB ((model WD2001FASS) and WD RE4 2 TB (model WD2003FYYS)HGST announced a similar structure in 2013
"WD® LAUNCHES HIGH-PERFORMANCE, 7200 RPM 2 TB HARD DRIVES FOR DESKTOP AND ENTERPRISE SYSTEMS," Western Digital Press Release,Sept. 1, 2009WD Dual Stage Actuator, annimation at UTube"Dual-Stage Actuator White Paper," HGST, October 2013