• 정보저장시스템학회논문집
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• 제3권4호
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• pp.191-195
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• 2007

The optical disc drive has used a high NA objective lens and a shorter wavelength laser diode for high recording density. But high NA and shorter wavelength cause several margins to become short. Focusing and tracking servo has to be more accurate and active tilt compensation mechanism is also needed for coma aberration compensation. In this paper, we proposed 3-axis moving magnet type actuator. For 3-DOF motion, moving coil actuator has to be equipped with 6 wires for supplying 3 independent signals. However, moving magnet type actuator doesn't need to change the configuration of wires because coils are in stator. So, we added a tilt mechanism to the 2-axis moving magnet actuator which is designed in previous research. Addition of the tilt mechanism cuts down the focus sensitivity. So, maximization the tilting sensitivity and securing the focusing sensitivity are objectivities of this research. DOE (design of experiments) procedures of electromagnetic circuit are performed for parameter study and the optimization is also performed to maximize the tilt sensitivity. And then the final design is suggested and its performance is verified by FE simulation.

• 정보저장시스템학회논문집
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• 제4권1호
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• pp.23-28
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• 2008

In this paper we suggested the moving magnet type actuator for optical disc drive which has high frequency of flexible mode. Generally, moving magnet type actuator has the advantage for increase the frequency of flexible mode. But it has low driving sensitivity due to the weight of its moving part. To overcome this shortcoming, we designed the model with the closed electromagnetic circuit for tracking direction. In addition, we improved the driving sensitivity and frequency of flexible mode by using of DOE (design of experiment) procedure for EM circuit. Consequently, it is verified that final designed model satisfied with the desired specifications.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.813-819
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• 2006

The state of the art for the design of swing ann actuators for optical disc drives is to obtain the high efficient dynamic characteristics, especially for the small size for the mobile information devices, It is affected by the need of consumers who wants the portable digital storage devices maintaining highly functional and removable characteristics of the optical disk drive (ODD). As a necessary consequence, the need of the small form factor (SFF) storage device has been considered as an important part in the information storage technology. In this paper. we suggest a new conceptual miniaturized swing arm type actuator that has high efficient dynamic characteristics as well as satisfies the sensitivity and the heat emission requirements for the SFF-ODD. It also uses a tracking electromagnetic (EM) circuit for a focusing motion. Due to the size constraint, the thermal problem of optical head arises; therefore, we design an efficiently heat emitted structure for the actuator.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.684-687
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• 2002

In optical disk drive(ODD), pickup actuator, which comprises a key part of an optical disk drive equipment. must be thin. compact, and high sensitive. Low tilt is also an important requirement for the actuator, since optical disks are to high density. This tilt occurs from around the axis parallel to the tangential and radial direction of the disk. The main reason of the moment is the coupling effect between focus driving system and tracking driving system. This paper analyzed tut quantity due to focusing and tracking force through coupled fields analysts with electromagnetic analysis and structural analysis.

• 한국소음진동공학회논문집
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• 제22권11호
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• pp.1128-1136
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• 2012

This paper analyzes the vibration characteristics of an optical pickup actuator, which has six wire-suspensions and is used in optical disc drives(ODDs). The vibration characteristics of the actuator is mathematically described by analyzing its beam configuration and motion condition confined to lateral and longitudinal directions of the beams. The accuracy of the vibration characteristics is proved by comparing mode frequencies with a finite element analysis. Finally, it is shown that mode frequencies and shapes can be modified by changing design parameters in mathematical expressions.

• 정보저장시스템학회논문집
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• 제2권3호
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• pp.208-213
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• 2006

The present state of the design of swing arm actuators for optical disc drives is to obtain the high efficient dynamic characteristics within a very compact volume. As a necessary consequence, the need of the small form factor (SFF) storage device has been arisen as major interests in the information storage technology. In this paper, we suggest the miniaturized swing arm type actuator that has high efficient dynamic characteristics for SFF optical disk drive (ODD). For the operating mechanism, it uses a tracking electromagnetic (EM) circuit for a focusing motion together. Moreover, due to the size constraint, the thermal stability of optical head is important. Therefore, the actuator is designed to emit the heat, which is generated by optical pick-up, along the actuator body easily. Initial model is designed based on the topology optimization method considering the thermal conductivity. Then, the structural parts of the actuator are modified to maintain the high sensitivity and to have wide control bandwidth by the design of experiments method (DOE) and new concept of decreasing mass and inertia. Finally, a swing arm type actuator for SFF ODD is suggested and its dynamic characteristics are verified.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제52권10호
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• pp.487-491
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• 2003

The low-cost, simple structured micropump which is actuated by piezoelectric-discs, is fabricated with polydimethylsiloxane (PDMS) and the performances of the micropump, such as pump rate and backpressure, are characterized. The PDMS micropump with diffusers instead of passive check valves as a flow-rectifying element was fabricated. The deflection of glass diaphragm measured by atomic force microscope (AFM) is about 0.4$\mu\textrm{m}$ when applying a 150V square wave voltage at 300Hz across a 300${\mu}\ell$ thick piezoelectric disc. While the square wave driving voltage is applied to the piezoelectric disc of the actuator, the flow rate is measured by fluid displacement variation of the outlet tube. The flow rate of micropump increases with enhancing the applied voltage due to the increase of diaphragm deflection. The flow rate and the backpressure of the micropump with diffusers are about 32.9${\mu}\ell$/min and 173Pa respectively for the above mentioned deflection conditions.

• Journal of Electrical Engineering and Technology
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• 제12권3호
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• pp.1073-1081
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• 2017

Inductive dynamic drives (IDD) are ultra rapid actuators where the moving part (disc) is subjected to impulse force. This paper presents the second model of inductive dynamic drive - a mechanical model where analytic- numerical approach was applied. The magnetic pressure, which was determined on the basis of the results obtained in the electrodynamic model, becomes the input data for mechanical model. Research with application of the mechanical model is necessary in order to determine the proper disc oscillation frequency and to obtain the stress state control for drive elements to be designed. Also, the selection of drive parameters to keep the disc deformation insignificant (while oscillating) is a condition under which these models do not need to be coupled together.

• 소음진동
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• 제9권5호
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• pp.984-990
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• 1999

This paper presents the geometrical methodology to decouple the vibration modes of an elastically supported single rigid body in three-dimensional space. It is shown that the vibration modes can be decoupled by placing the center of elasticity at suitable locations and thereby yielding the plane(s) of symmetry for the given stiffness matrix. The developed methodology has been applied to the actuator supported by the 4-wire suspensions in optical discs, which has one plane of symmetry. For this numerical example, the axes of vibrations have been computed and illustrated with the natural frequencies. The forced response at the objective lens is represented and its geometrical interpretation has been explained as the mutual moment between the axis of vibration and the applied wrench times the line coordinates of the axis of vibration.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 추계학술대회 논문집
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• pp.792-798
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• 2012

This study shows the vibration characteristics of an actuator with six wire-suspensions, used in optical pickups of optical disc drives (ODDs). In this paper, the vibration characteristics of this beam structure is induced mathematically. To obtain vibration modes of focusing direction, the vibration analysis is achieved in lateral and longitudinal directions of the structure. The accuracy of induced vibration characteristics is proved by comparing mode frequencies with a finite element analysis. Finally, it is shown that mode shapes can be modified by changing design parameters in mathematical expressions.