Title :
High-bandwidth HDD tracking servo by a moving-slider micro-actuator
Author :
Hirano, Toshiki ; Fan, Long-Sheng ; Semba, Tetsuo ; Lee, Wen Y. ; Hong, Jonggi ; Pattanaik, S. ; Webb, Patrick ; Juan, Wen-Han ; Chan, Susanna
Author_Institution :
Res. Div., IBM Corp., San Jose, CA, USA
fDate :
9/1/1999 12:00:00 AM
Abstract :
This paper describes a micro-actuator for high-bandwidth tracking servo, where a micro-actuator is attached between slider and suspension, and moves the slider relative to the suspension. The micro-actuator frequency response measurement proved that this micro-actuator can be modeled as an ideal spring-mass-damper system up to 80 kHz, so that very high bandwidth servo system can be easily designed. The maximum servo bandwidth of 6.4 kHz was achieved in a drive level experiment, which is the highest bandwidth ever demonstrated as a drive level. A rapid step response time of 0.2 mS for 0.6 μm step was also achieved. The experimental bandwidth was not limited by the micro-actuator´s resonance mode, but the saturation of the micro-actuator driver
Keywords :
disc drives; frequency response; hard discs; microactuators; servomechanisms; step response; transfer functions; 6.4 kHz; HDD tracking servo; driver saturation; frequency response; high-bandwidth; ideal spring-mass-damper system; moving-slider microactuator; open loop transfer function; rapid step response time; Actuators; Bandwidth; Delay; Frequency measurement; Frequency response; Magnetic heads; Microactuators; Resonance; Servomechanisms; Silicon;
Journal_Title :
Magnetics, IEEE Transactions on