• 한국자동차공학회논문집
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• 제6권1호
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• pp.163-181
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• 1998

In this study, the objective is determine the optimal design variable of engine mount system using the rubber mount of bush-type which is usually utilized in passive control to minimize vibrations of vehicle body or transmission from engine into body. The engine model adopted in this study is 4-cylinder, 4-stroke gasoline engine support- ed by 4-points. The system is modelled in 10 d.o.f.-rigid body motion of the engine & transmission in 6 d.o.f., elastic motion of vehicle body in 4 d.o.f.(1st torsional, 1st vertical and 1st & 2nd lateral bending vibration mode). To consider the elastic motion of vehicle body, find the eigenvalues and mode shapes of vehicle body by nodal testing and then determine the modal masses and stiffnesses of the body. The design variables of the engine mount system are locations, stiffness and damping coefficients of the rubber mounts(28 design variables). In case of considering the torque-roll axis for the engine, the design variables of the mount system are reduced to 22 design variables. The objective functions in optimal design process are considered by three cases, that is, 1) transmitted forces through engine mounts, 2) acceleration components of generalized coordinates for the vibration of vehicle body, 3) acceleration of specified location(where gear box) of body. three case are analyzed and compared with each other.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.700-704
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• 2002

To design engine mount system efficiently, lots of analysis works are conducted for the prediction of the dynamic behavior of a vehicle as varying design parameters of the engine mount system. Thus it is very important to choose an appropriate analysis software. Because one usually carries out different types of analysis based on relatively simple models, so using a specialized in-house software is more effective than using several commercial softwares. In this paper a case study is introduced to develop an analysis software to design engine mount system.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1996년도 추계학술대회논문집; 한국과학기술회관, 8 Nov. 1996
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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.

• 한국소음진동공학회논문집
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• 제18권11호
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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.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.399-404
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• 2002

Analyzing acoustic-structural systems such as automobiles and aircraft the FRF-based substructuring method is one of the most powerful tools. In this paper, an optimization procedure far the engine mount system of passenger car has been presented using the design sensitivity analysis based on the multi-domain FRF-based substructuring formulation. The proposed method is applied to an optimization problem of the engine mount system, of which objective is to minimize the interior sound over the concerned rpm range. The design variables selected are the stiffnesses of the engine mounts and bushes. Plugging the gradient information calculated by the proposed method into nonlinear optimization software, we can obtain the optimal stiffnesses of the engine mounts and bushings through design iterations. The optimized interior noise in the passenger car shows that the proposed method is very useful in the realistic situation.

• 오토저널
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• 제10권2호
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• pp.39-45
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• 1988

The analytical model of an engine mount system with six degrees of freedom is identified using the modal parameters obtained from the experimental modal analysis. The structural parameters, mass moment of inertia of the engine block and stiffness of the rubber mounts, of the engine mount system are determined by using the condition that the estimated model parameters should satisfy the corresponding eigenvalue problem. The simulated modal parameters of the identified analytical model are in good agreement with the measured modal parameters.

• 대한기계학회논문집
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• 제10권5호
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• pp.689-697
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• 1986

본 연구에서는 3자유도(3방향의 병진운동만 고려) 고무마운트모형의 타당성을 검증하기 위하여, 먼저 고무자체의 물성치인 강성계수와 감쇠계수를 진동수와 초기변 형률에 따라 실험을 통해 구하였다. 질량행렬의 모든요소를 쉽게 구할 수 있는 간단 한 시험구조물을 제작하고 여기에 고무아운트를 부착하여 6자유도를 갖는 모의 엔진- 마운트계를 구성한 후 가진실험을 통해 얻은 오무드 매개변수들과 고무의 물성치를 이 용한 컴퓨터 시뮬레이션의 결과를 비교함으로써 고무아운트 모형의 타당성을 검증하였 다. 특히 본 연구에는 유압가진 실험으로부터 얻은 실험결과를 바탕으로 고무의 강 성계수를 주파수의 1차함수로 고려한 경우와 전진동수 영역에서 균일하다고 가정하는 경우를 비교하였다.

• Journal of Biosystems Engineering
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• 제29권5호
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• pp.385-394
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• 2004

The objectives of this study were to investigate the effectiveness of rubber as an engine mount of walking-type cultivators and to determine its optimal spring constant and damping coefficient using a dynamic simulation of the engine mount system. Four different types of rubber mounts were tested to determine their spring constants and damping coefficients, and the best type was selected for the isolation of the engine vibrations transmitted to the handle. The total vibration levels transmitted to the handle when the rubber mounts weren't installed were 17.52 $m/s^2$. The total vibration levels transmitted to the handle when the rubber mounts were installed were 10.69 $m/s^2$ for Stripe 1, 11.33$m/s^2$ for Stripe 2, 10.92$m/s^2$ for Stripe 3 and 14.19$m/s^2$ for Hive, respectively, resulting in an average of $30\%$ reduction when compared with that without the engine mount. A dynamic model of the cultivator's engine-mount system and its simulation program were developed and verified. A method was proposed to determine the optimal spring constant and damping coefficient of the engine-mount system. It was found from the simulation that a spring constant of 4,100 kN/m and the largest damping coefficient were the most effective for the vibration isolation.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 추계학술대회논문집
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• pp.284-285
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• 2008

For development of low fuel consumption vehicle, design of engine can he changed and it brings collateral effect. Abnormal vibration is one of bad effect of high efficiency engine and it can be got over by active engine mount system. For development of active engine mount system, an adequate experimental equipment is required which contain characteristic of real engine movement. To make adequate experimental equipment, regulated force vibrating system including characteristics of vehicle chassis is required.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 추계학술대회논문집
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• pp.282-283
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• 2008

According to the development of vehicle technique, the improved NVH performance is required in the vehicle which have the high effectiveness and the high output of the powertrain. This vehicle has to be adapted to active engine mounting system to reduce the vibration in accordance with various vehicle information. The pneumatic active engine mounting system is consist with engine mount, solenoid valve, air tank and control unit totally. The important technique of this system is to reduce the vibration by the air pressure. This paper contains the development process of the pneumatic active engine mounting system and confirm the performance of this system test and vehicle test.