• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.792-796
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• 2013

A practical process to optimize engine mounts on construction equipment is presented in this research. Transmitted force from the engine is estimated by using stiffness of the mount rubber which varies with frequency, amplitude and pre-load, and by the engine excitation force that comes from piston mass and gas pressure and so on. The transmitted force is measured through TPA(Transfer Path Analysis) and is then compared with the estimated force. The optimum mount position and stiffness are solved using MATLAB. The result shows the improvement on engine mount vibration.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.283-286
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• 2004

This work presents a 3-axis active mount featuring the piezoelectric stack actuators. The inertia configuration for the piezoelectric actuators is adopted to achieve appropriate force and moment in each axis. In addition, the rubber mount is integrated to provide stiffness for system loading. In order to analyze the active mount, the governing equation for the force and moment is derived and its validity is demonstrated by comparing generated force and moment of each actuator between analysis and experiment. In addition, the natural frequency of each actuator is identified though both simulation and experiment.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1996.10a
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• pp.330-337
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• 1996

The purpose of engine mount system is to reduce the noise and vibration caused by engine vibration, and to decouple the roll and bounce mode at idle. To reduce the noise and vibration level in a vehicle, it is important to make the design optimization of engine mount system that considered the moment of inertia and inclination of mount rubber. As a result, according to the definition of Torque Rool Axis (TRA), the vibration axis at idle must be on the TRA or very close to it. In this paper, we studied the effect of the design optimization of engine mount system. And we have a good NVH performance.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.10
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• pp.1056-1061
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• 2012

FEM analysis is essential to shorten the development time and reduce the cost for developing high-performance machine tools. Mount joint parts play important role to ensure static and dynamic stability of machine tools. This paper suggests a computational modeling of mount joint part of machine tools. MATRIX27 element of ANSYS is adopted to model mount joint parts. MATRIX27 allows the definition of stiffness and damping matrices in matrix form. The matrix is assumed to relate two nodes, each with six degrees of freedom per node. Stiffness and damping values of commercial mount products are measured to build a database for FEM analysis. Jack mounts with rubber pad are exemplified in this paper. The database extracted from the experiments is also used to estimate of stiffness and damping of untested mounts. FEM analysis of machine tools system with the suggested mount computational model is performed. Static and dynamic results prove the feasibility of the suggested mount model.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.87-91
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• 2013

Rubber Components have been playing important role for the isolation of noise and vibration of vehicle. This paper is presented the new method of dynamic modeling of rubber component for simulating the dynamic characteristics of it under the varing loading condition. Rubber dynamic model consists of the hyperelastic, viscoelastic and elasto-plastic characteristics of rubber. Dynamic proporties of rubber are calculated at each preload and frequency conditions, compared to test data, and evaluated the validity of rubber dynamic model. This technique is expected to understand and improve the characteristics of noise and vibration with relation to rubber components.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.244-249
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• 2002

Rubber seat is extensively used to reduce the vibration of machine or structure. Over the years an enormous effort has been put into developing procedures to provide properties of rubber material for design function. However, there are still a lot of difficulties to analyze static characteristics of rubber components with hyper elasticity and nonlinear large deformation. In this paper material property is obtained by strain-stress curve using a tension test. Mooney-Rivlin Coefficients are gotten by fitting strain-stress curve. The visco-elastic characteristics of refrigerator rubber mount is determined by using ANSYS. And to minimize the rubber stiffness, the rubber seat shape optimization is performed.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.710-715
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• 2001

Rubber is used extensively in many industries because of its large reversible elastic deformation, excellent damping and energy absorption characteristics, and wide availability. It becomes very important to predict the fatigue life of rubber components. But a great deal of time and cost are necessary for the fatigue test of rubber components. In this study the fatigue life of rubber components is evaluated by performing the fatigue test of a specimen and FE analysis. The fatigue life of Jang-gu type specimen which is considered as a simple rubber component is predicted and compared with experimental results. Its material is natural rubber of which hardness is 60 and used for the engine mount of commercial vehicles.

• Journal of KSNVE
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• v.9 no.6
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• pp.1247-1258
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• 1999

This paper presents vibration control of a CD-ROM(compact disc-read only memory) drive feeding system consisting of a new type of CD-ROM mount using an electro-rheologocal(ER) fluid. Chemically treated starch particles and silicon oil are used for EF fluid, and its field-dependent yield stresses are experimentally distilled under both the shear and the flow modes. On the basis of the yield stress, an appropriate size of ER CD-ROM mount adapted to conventional feeding system is designed and manufactured. Vibration isolation performance of the proposed mount is evaluated in the frequency domain and compared with that of conventional rubber mount. The ER CD-ROM mount is then installed to the drive feeding system and the system equation of motion is derived. The skyhook controller is then incorporated with the fuzzy technique to improve the performance of ER CD-ROM mount. A set of fuzzy parameters and control rules are obtained from a relation between vertical displacement and pitching motion of the feedng system. Followingthe formulation of the fuzzy-skyhook controller, computer simulation is undertaken in order to evaluate vibration suppression of the CD-ROM drive feeding system subjected to various excitations.

• Journal of the Society of Naval Architects of Korea
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• v.45 no.3
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• pp.288-295
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• 2008

Passive-type control devices such as resilient mounts and wire rope isolators are generally used for protecting the shipboard equipment from shock loading and for suppressing the mechanical vibration of the equipment in naval ships. To improve the performance of the control device, a new hybrid mount is under development in this study. This mount consists of a passive-type rubber element and an active-type piezo-stack element. It can be expected that the mount has enhanced performance of about 20 dB or more with respect to transmissibility through a series of performance tests of prototype mount.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.11
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• pp.1150-1156
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• 2008

This paper presents vibration control of an active hybrid engine mount featuring a magneto-rheological(MR) fluid and a piezostack actuator. The MR fluid is adopted to improve isolation performance at resonant frequencies, while the piezostack actuator is adopted for performance improvement at non-resonant frequencies, especially at high frequencies. Based on some particular practical requirements of engine mounts, the proposed mount is designed and manufactured. The characteristics of rubber element, piezostack actuator and MR fluid are verified for system analysis and controller synthesis. The dynamic model of the proposed mount with a supported mass (engine) is established. In this work, a sliding mode controller is synthesized for the mount system to reduce vibrations transmitted from the engine in a wide frequency range. Computer simulations are performed to evaluate control performances of the proposed active engine mount in time and frequency domains.