• Title/Summary/Keyword: A cantilevered beam

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Vibration Response Characteristics of the ERP-Cantilevered Beam Under Electrode Gap Change (전극 간극 변화에 따른 ERF-외팔보의 진동응답 특성)

  • 윤신일;최윤대;한상보
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2002.04a
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    • pp.457-462
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    • 2002
  • This paper describe the vibration characteristics of cantilevered beam filled with ERF subjected to variousr electrode charge. The Proposed ER fluids used in the present study consists of starch particles and silicon oil. The ER fluids undergo a phase-change when subjected to an external electric filed. This Paper Presents performance analyses of three types of the cantilevered beam with different electrode gaps and applied electric fields.

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Strain Rate Self-Sensing for a Cantilevered Piezoelectric Beam

  • Nam, Yoonsu;Sasaki, Minoru
    • Journal of Mechanical Science and Technology
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    • v.16 no.3
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    • pp.310-319
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    • 2002
  • This paper deals with the analytical modeling, and the experimental verification of the strain rate self-sensing method using a hybrid adaptive filter for a cantilevered piezoelectric beam. The piezoelectric beam consists of two laminated lead zirconium titanates (PZT) on a metal shim. A mathematical model of the beam dynamics is derived by Hamilton's principle and the accuracy of the modeling is verified through the comparison with experimental results. For the strain rate estimation of the cantilevered piezoelectric beam, a self-sensing mechanism using a hybrid adaptive filter is considered. The discrete parts of this mechanism are realized by the DS1103 DSP board manufactured by dSPACE$\^$TM/. The efficacy of this method is investigated through the comparison of experimental results with the predictions from the derived analytical model.

Plastic collapse of tapered, tip-loaded cantilevered beams

  • Wilson, James F.;El-Esnawy, Nayer A.
    • Structural Engineering and Mechanics
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    • v.9 no.6
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    • pp.569-588
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    • 2000
  • The plastic collapse loads and their locations are predicted for a class of tapered, initially curved, and transversely corrugated cantilevered beams subjected to static tip loading. Results of both closed form and finite element solutions for several rigid perfectly plastic and elastic perfectly plastic beam models are evaluated. The governing equations are cast in nondimensional form for efficient studies of collapse load as it varies with beam geometry and the angle of the tip load. Static experiments for laboratory-scale configurations whose taper flared toward the tip, complemented the theory in that collapse occurred at points about 40% of the beams length from the fixed end. Experiments for low speed impact loading of these configurations showed that collapse occurred further from the fixed end, between the 61% and 71% points. The results may be applied to the design of safer highway guardrail terminal systems that collapse by design under vehicle impact.

Computational Study on Aeroacoustics of an Elastic Cantilevered Trailing-Edge (탄성 날개 끝단의 공력 소음에 관한 전산해석 연구)

  • Hwang Bon Chang;Moon Young June
    • 한국전산유체공학회:학술대회논문집
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    • 2005.04a
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    • pp.159-168
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    • 2005
  • Noise generated by the blunt trailing edge of lifting surfaces is investigated in this study using fluid structure interaction theory. First, through the eddy modeling, noise generation doe to the flow instability on the rigid trailing edge is surveyed. Then the behavior of elastic cantileverd beam is investigated. Parametric study based on various material properties is employed to analyze the motion of the beam. Moreover, each eigenmode approach of cantilevered beam is used to find when flow induced vibration is resonant. To analyze elastic behavior of cantilever beam efficiently, moving grid generation technique based on non-conservative form of Navier-Stokes equation is used. Equation of the motion associated with the cantilever beam is discretized by the Galerkin procedure with forced vibration. As a consequence, behavior of the elastic cantilevered beam is stable when the first mode natural frequency of the material is relatively higher than that of flow induced pressure fluctuation.

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Experimental Verification on Dynamic Responses of a Cantilevered Beam under a Moving Mass with Accelerations (가속을 갖는 이동질량에 의한 외팔보의 동적응답에 관한 실험적 검증)

  • Kim, H.J.;Ryu, B.J.;Kim, H.J.;Yoon, C.S.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2004.11a
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    • pp.307-310
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    • 2004
  • The paper presents the numerical and experimental results for the dynamic response vibration of a cantilevered beam subjected to a moving mass with variable speeds. Governing equations of motion under a moving mass were derived by Galerkin's mode summation method taking into account the effects of all forces due to moving mass, and the numerical results were calculated by Runge-Kutta integration method. The effects of the speed, acceleration and the magnitude of the moving mass on the response of the beam are fully investigated. In order to verify numerical results, some experiments were conducted, and the numerical results have a little difference with the experimental ones.

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Dynamic Stability of a Cantilevered Timoshenko Beam on Partial Elastic Foundations Subjected to a Follower Force

  • Ryu, Bong-Jo;Shin, Kwang-Bok;Yim, Kyung-Bin;Yoon, Young-Sik
    • Journal of Mechanical Science and Technology
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    • v.20 no.9
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    • pp.1355-1360
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    • 2006
  • This paper presents the dynamic stability of a cantilevered Timoshenko beam with a concentrated mass, partially attached to elastic foundations, and subjected to a follower force. Governing equations are derived from the extended Hamilton's principle, and FEM is applied to solve the discretized equation. The influence of some parameters such as the elastic foundation parameter, the positions of partial elastic foundations, shear deformations, the rotary inertia of the beam, and the mass and the rotary inertia of the concentrated mass on the critical flutter load is investigated. Finally, the optimal attachment ratio of partial elastic foundation that maximizes the critical flutter load is presented.

Dynamic Analysis of Cantilevered Curved Beam using Model Analysis Method (모우드 해석법을 이용한 캔틸레버 곡선보의 동적해석)

  • Kim, Young-Moon;You, Ki-Pyo
    • Journal of Korean Association for Spatial Structures
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    • v.7 no.1 s.23
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    • pp.55-62
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    • 2007
  • The Paper presents three methods for calculating the natural frequencies of cantilevered curved Beams. A summary is given of the development of two techniques: theoretic value and the result of the experiment. Theoretic value of curved beam vibration analysis are derived from complementary variational principles assuming as unknown stress-displacement result fields. In order to perform free vibration analysis of curved beam, Aluminum-made cantilevered curved beam is used in experiment. Experimental input and output signals are derived from the impact hammer and the one accelemeter are amplificated by an amplifier. The validity of the modal analysis method

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Active vibration suppression of a 1D piezoelectric bimorph structure using model predictive sliding mode control

  • Kim, Byeongil;Washington, Gregory N.;Yoon, Hwan-Sik
    • Smart Structures and Systems
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    • v.11 no.6
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    • pp.623-635
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    • 2013
  • This paper investigates application of a control algorithm called model predictive sliding mode control (MPSMC) to active vibration suppression of a cantilevered aluminum beam. MPSMC is a relatively new control algorithm where model predictive control is employed to enhance sliding mode control by enforcing the system to reach the sliding surface in an optimal manner. In previous studies, it was shown that MPSMC can be applied to reduce hysteretic effects of piezoelectric actuators in dynamic displacement tracking applications. In the current study, a cantilevered beam with unknown mass distribution is selected as an experimental test bed in order to verify the robustness of MPSMC in active vibration control applications. Experimental results show that MPSMC can reduce vibration of an aluminum cantilevered beam at least by 29% regardless of modified mass distribution.

Dynamic Response of Cantilevered Beams Subjected to a Travelling Mass with a Constant Acceleration (일정 가속 주행질량에 의한 외팔보의 동적응답)

  • 류봉조;윤충섭;김희중;이규섭
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2004.05a
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    • pp.320-325
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    • 2004
  • The paper deals with the dynamic response of a cantilevered beam under a travelling mass with constant acceleration. Governing equations of motion taking into account all inertia effects of the travelling mass are derived by Galerkin's mode summation method, and Runge-Kutta integration method is applied to solve the differential equations. The effects of the speed, acceleration and the magnitude of the travelling mass on the response of the beam are fully investigated. A variety of numerical results allows us to draw important conclusions for structural design purposes.

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Dynamic Response Analysis of a Cantilever Beam due to Elastic Impact (탄성충돌에 의한 외팔보의 동적 응답해석)

  • Han, Hyun-Hee;Ryu, Bong-Jo;Lee, Kang-Soo;Shin, Kwang-Bok;Ahn, Ji-Youn;Lee, Gyu-Seop
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.05a
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    • pp.1065-1070
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    • 2006
  • The beam structure models with an impactor or contact parts under impact forces have teen applied to the design of mechanical and electronic accessories. Switches, hard-disk pick-ups and sensors are typical structural examples of the structure to be designed to colliding with other parts of structures. In this paper, in order to examine the relationships between the changes of the stiffness and damping of the impactor and vibrations of the dynamic characteristics of the impact model of a cantilevered beam with an impactor, impact force of the impactor and response characteristics of the cantilevered beam were analyzed by both numerical simulation and experiment. Since the stiffness and damping of the impactor have high nonlinear characteristics, the contact model using revised Herz-model was established by experiments. Also, the results of numerical analyses for dynamic response and impact force of a cantilevered beam with an impactor have a good agreement with experimental results.

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