A phase-stabilized servo controller for dual-stage actuators in hard disk drives

A design of a phase-stabilized servo controller based on a Nyquist plot for a moving-suspension-type dual-stage actuator is proposed. The phase-stabilized servo controller utilizes suspension resonances of a PZT actuator to compensate track misregistration (TMR) due to windage disturbances excited by suspension vibration. Experimental results on a prototype 3.5-inch hard disk drive show that the cross-over frequency is 2.0 kHz and the windage disturbances are reduced by 23% compared to a conventional notch-based dual-stage controller.

[1]  Lennart Ljung,et al.  System Identification: Theory for the User , 1987 .

[2]  Hiromu Hirai,et al.  Multi-sensing servo with carriage-acceleration feedback for magnetic disk drives , 1998, Proceedings of the 1998 American Control Conference. ACC (IEEE Cat. No.98CH36207).

[3]  William C. Messner,et al.  Design and analysis of a high bandwidth disk drive servo system using an instrumented suspension , 1999 .

[4]  R. Horowitz.  Track seek control for hard disk dual-stage servo systems , 2000, 2000 Asia-Pacific Magnetic Recording Conference. Digests of APMRC2000 on Mechanical and Manufacturing Aspects of HDD (Cat. No.00EX395).

[5]  Toshihiko Shimizu,et al.  Development of a /spl Phi/-shaped actuated suspension for 100-kTPI hard disk drives , 2001 .

[6]  Takenori Atsumi,et al.  High-bandwidth servo control designs for magnetic disk drives , 2001, 2001 IEEE/ASME International Conference on Advanced Intelligent Mechatronics. Proceedings (Cat. No.01TH8556).

[7]  R. Horowitz,et al.  Active vibration control of a PZT actuated suspension in hard disk drives , 2002, Proceedings of the 2002 American Control Conference (IEEE Cat. No.CH37301).