• Title/Summary/Keyword: compliant

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Development of Compliant and Dissipative Joints in Coupled Thin Plates for Vibrational Energy Flow Analysis (평판 구조물의 진동 파워흐름해석을 위한 비보존 조인트 개발)

  • Song, Jee-Hun;Hong, Suk-Yoon
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.18 no.10
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    • pp.1082-1090
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    • 2008
  • In this paper, a general solution for the vibrational energy and intensity distribution through a compliant and dissipative joint between plate structures is derived on the basis of energy flow analysis (EFA). The joints are modeled by four sets of springs and dashpots to show their compliancy and dissipation in all four degrees of freedom. First, for the EFA, the power transmission and reflection coefficients for the joint on coupled plate structures connected at arbitrary angles were derived by the wave transmission approach. In numerical applications, EFA is performed using the derived coefficients for coupled plate structures under various joint properties, excitation frequencies, coupling angles, and internal loss factors. Numerical results of the vibrational energy distribution showed that the developed compliant and dissipative joint model successfully predicted the joint characteristics of practical structures vibrating in the medium-to-high frequency ranges. Moreover, the intensity distribution of a compliant and dissipative joint is described.

Correlation Between the Composition of Compliant Coating Material and Drag Reduction Efficiency (유연벽면 점탄성 소재 배합비와 저항저감 효과의 상관관계)

  • Lee, In-Won;An, Nam-Hyun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.33 no.6
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    • pp.389-395
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    • 2009
  • A specially designed flat plate was mounted vertically over the axial line in the wind tunnel of the Pusan National University. Strain balances were mounted in the trailing part of the plate to measure the skin friction drag over removable insertions of $0.55{\times}0.25m^2$ size. A set of the insertions was designed and manufactured: 3 mm thick polished metal surface and three compliant surfaces. The compliant surfaces were manufactured of a silicone rubber Silastic$^{(R)}$ S2 (Dow Corning company). To modify the viscoelastic properties of the rubber, its composition was varied: 90% rubber + 10% catalyst (standard), 92.5% + 7.5% (weak), 85% + 15% (strong). Modulus of elasticity and the loss factor were measured accurately for these materials in the frequency range from 40 Hz to 3 kHz. The aging of the materials (variation of their properties) for the period of one year was documented as well. Along with the drag measurement using the strain balance, velocity and pressure were measured for different coating. The strong compliant coating achieved 5% drag reduction within a velocity range $20{\sim}40$ m/s while standard and weak coatings increased drag reduction.

A Piezo-driven Ultra-precision Stage for Alignment Process of a Contact-type Lithography (접촉식 리소그라피의 정렬공정을 위한 압전구동 초정밀 스테이지)

  • Choi, Kee-Bong;Lee, Jae-Jong;Kim, Gee-Hong;Lim, Hyung-Jun
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.20 no.6
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    • pp.756-760
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    • 2011
  • This paper proposed an alignment stage driven by piezo actuators for alignment process of a contact-type lithography. Among contact-type lithography processes, an UV-curable nanoimprint process is an unique process to be able to align patterns on upper and lower layers. An alignment stage of the UV-curable nanoimprint process requires nano-level resolution as well as high stiffness to overcome friction force due to contact moving. In this paper, the alignment stage consists of a compliant mechanism using flexure hinges, piezo actuators for high force generation, and capacitive sensors for high-resolution measurement. The compliant mechanism is implemented by four prismatic-prismatic compliant chains for two degree-of-freedom translations. The compliant mechanism is composed of flexure hinges with high stiffness, and it is directly actuated by the piezo actuators which increases the stiffness of the mechanism, also. The performance of the ultra-precision stage is demonstrated by experiments.

A SHAPE OPTIMIZATION METHOD USING COMPLIANT FORMULATION ASSOCIATED WITH THE 2D STOKES CHANNEL FLOWS

  • Kim, Hongchul
    • Korean Journal of Mathematics
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    • v.16 no.1
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    • pp.25-40
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    • 2008
  • We are concerned with a free boundary problem for the 2D Stokes channel flows, which determines the profile of the wing for the channel, so that the given traction force is to be distributed along the wing of the channel. Using the domain embedding technique, the free boundary problem is transferred into the shape optimization problem through the compliant formulation by releasing the traction condition along the variable boundary. The justification of the formulation will be discussed.

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Force Reflecting and Compliant Control for Heavy-Duty Power Manipulators (고하증 원격조작기의 힘반영 유연성 제어)

  • Ahn, Sung-Ho;Yoon, Ji-Sup;Lee, Sang-Jeong
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.2907-2909
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    • 2000
  • This paper proposes a force reflecting and compliant control scheme for the heavy-duty power manipulators with high ratio gear reducers at its joints. From the experimental results. it can be seen that the proposed scheme has an excellent compliant force control performance.

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Low frequency noise reduction by coupling with membrane (박막과의 연성에 의한 저주파 소음 저감)

  • 박수경;김양한
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1996.10a
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    • pp.148-152
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    • 1996
  • A method of deminishing low frequency noise by acoustic acoupling with compliant wall is described. The coupled governing equations and boundary conditions are derived and solved. The coupled system shows very interesting behavior in the low frequency region; in the low frequency, acoustic wave doesn't propagate, but decay to satisfy the boundary condition with the compliant wall. Henceforth using this mechanism, we propose a method of reducing low frequency noise, which is infact related with the physical properties of compliant wall. The method has been experimentally verified.

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Planning of Compliant Motions for Fixture Loading

  • Yu, Kyeonah
    • Transactions on Control, Automation and Systems Engineering
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    • v.2 no.1
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    • pp.62-68
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    • 2000
  • Fixtures are used in almost all phases of machining and assembly to position and hold a part accurately. The class of fixture which consists of 3 locators and 1 clamp(3L/1C) is known as the minimal set that can provide form closure which is a kinematic constraint condition for preventing all planar motions. This type of fixtures has advantages in terms of the number of fixture elements required, the time for clamping, and so on. However it is not widely used in industry because reliable loading scheme has not been reported. In this paper, we propose a method to load the class of 3L/1C fixtures using compliant motions. The planner is developed for synthesizing compliant motions to achieve precise final fixture configuration in the presence of sensing and control uncertainties. A novel approach to eliminate uncertainty in part orientation by adding one extra fixture element called an aligning pin is proposed.

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A Shared Compliant Control Scheme based on Internal Model Control

  • Ahn, Sung-Ho;Jin, Jae-Hyun;Park, Byung-Suk;Yoon, Ji-Sup
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.1571-1574
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    • 2003
  • A shared compliant control scheme based on IMC is proposed for the position-force force reflecting control system. The controller of the slave manipulator is designed by IMC method for the open loop unstable plant. The compliant control is implemented by first order low pass filter. In the proposed scheme, the slave manipulator well tracks the position of the master manipulator in free space and the compliance of the slave manipulator is autonomously controlled in contact condition. The simulation results show that the excellence of the proposed controller.

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Implementation of VSIA 2.2 compliant Soft-IP about 2-4-8 DCT/IDCT core used for DVCR (DVCR용 2-4-8 DCT/IDCT core의 VSIA 2.2 compliant Soft-IP가공)

  • 민경욱;박보윤;이영호;정정화
    • Proceedings of the IEEK Conference
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    • 2000.06b
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    • pp.157-160
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    • 2000
  • 본 논문에서는 DVCR용 2-4-8 DCT core의 VSIA(Virtual Socket Interface Allience) 2.2 compliant IP의 구현에 대하여 기술한다. 본 논문에서 기술한 2-4-8 DCT/IDCT core는 Soft IP이며, VSIA의 deliverable document ver. 2.2에서 정의한 Soft-IP에 대한 72가지의 필수 항목, 조건부 필수 항목, 권고 항목 등의 전달물을 각 DWG(Development Working Group)의 사양에서 정의하고 있는 규격에 맞추어 가공하였다. 또한 본 논문에서는 Soft-IP에 대한 VSIA 권고안 및 VSIA deliverable list에 대하여 기술하고, VSIA compliant IP화를 위한 방법에 대하여 설명하였다.

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Compliant Mechanism Design with Geometrical Advantage (입 . 출력변위비를 고려한 컴플라이언트 메커니즘 설계)

  • Kim, Young-Gi;Min, Seung-Jae
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.27 no.5
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    • pp.764-771
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    • 2003
  • To control the motion generated by a compliant mechanism the design method using specified geometrical advantage is proposed. The optimization problem is formulated to minimize the difference between the specified and the current geometrical advantage of a mechanism and topology optimization is applied to determine the layout of a mechanism. The results of several test problems including a displacement converter design and a gripper design are compared with a multi-criteria model and show that the design of an accurate compliant mechanism with specified geometrical advantage can be obtained.