High density servo signal detection for accurate head positioning

High-density magnetic hard disks are key components in information storage. In high-density hard disk drives (HDD), both super fast track seeking and extremely accurate positioning of the read/write head are required. A new multiDOF piezoelectric micro-actuator with nano-transverse and micro-lateral control of the head positioning system for highdensity hard disk drives is proposed. For the track following control of a head positioning system in the HDD, proper modeling of the system including the voice coil motor (VCM), suspension, slider, and gimbal system is very important. Before further comprehensive analysis of the whole assembly, the design concept and the evaluation of the micro-actuator are focused on in this paper. First, design of the new piezoelectric micro-actuator is illustrated. The design of the new micro-actuator is based on the axial deformation of piezoelectric elements for lateral motion control and the bimorph actuation of piezoelectric elements for transverse nm motion control. Next, mathematical models of the micro-actuator system are defined. Lastly, the micro-actuator system is modeled using the commercial finite element package ANSYS. The results from analytical analysis and FE analysis are compared. Static response of the micro-actuator system is evaluated first, followed by analysis of dynamic response analysis. Static actuations of the new actuator system satisfy both lateral (±0.1μm) and transverse (15nm) specifications. Dynamic analysis of the ultra-precision system suggests that the new piezoelectric micro-actuator improves performance of highdensity hard disk drives by increasing servo bandwidth and decreasing flying height.

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304 Head Positioning Control System for High-Density Recording of Next Generation Optical Disk Drives

The Proceedings of the Symposium on the Motion and Vibration Control ◽

10.1299/jsmemovic.2001.7.353 ◽

2001 ◽

Vol 2001.7 (0) ◽

pp. 353-355

Author(s):

Motoaki SHIMIZU ◽

Masashi KUBOTA ◽

Naotoshi IWAZAWA

Keyword(s):

Control System ◽

Optical Disk ◽

High Density ◽

Disk Drives ◽

Next Generation ◽

Positioning Control ◽

Head Positioning ◽

High Density Recording

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Holographic Servo-signal Detection Stabilized to the Wavelength Fluctuation and the Mechanical Misalignment in the Optical Heads.

10.1117/12.952751 ◽

1989 ◽

Cited By ~ 3

Author(s):

Makoto Kato ◽

Tetsuo Saimi ◽

Shin-ichi Kadowaki ◽

Yoshiaki Komma

Keyword(s):

Signal Detection ◽

Servo Signal

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A novel, sensitive detection system for high-density microarrays using dendrimer technology

Physiological Genomics ◽

10.1152/physiolgenomics.2000.3.2.93 ◽

2000 ◽

Vol 3 (2) ◽

pp. 93-99 ◽

Cited By ~ 139

Author(s):

ROBIN L. STEARS ◽

ROBERT C. GETTS ◽

STEVEN R. GULLANS

Keyword(s):

Signal Detection ◽

Detection System ◽

High Density ◽

Sensitive Detection ◽

High Signal ◽

Single Chip ◽

Reverse Transcription Reaction ◽

Multichannel Detection ◽

Genomics Research ◽

Amplification System

Stears, Robin L., Robert C. Getts, and Steven R. Gullans. A novel, sensitive detection system for high-density microarrays using dendrimer technology. Physiol Genomics 3: 93–99, 2000.—To improve signal detection on cDNA microarrays, we adapted a fluorescent oligonucleotide dendrimeric signal amplification system to microarray technology. This signal detection method requires 16-fold less RNA for probe synthesis, does not depend on the incorporation of fluorescent dNTPs into a reverse transcription reaction, generates a high signal-to-background ratio, and can be used to allow for multichannel detection on a single chip. Furthermore, since the dendrimers can be detected individually, it may be possible, by employing dendrimer-binding standards, to calculate the numbers of bound cDNAs can be estimated. These features make the dendrimer signal detection reagent ideal for high-throughput functional genomics research.

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