• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 춘계학술대회 논문집
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• pp.520-525
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• 2011

As worldwide concern stands on global warming and greenhouse gases from internal combustion engine, the interests in technologies for a highly efficient powertrain has been increased. Concurrently the investigation to improve the deteriorated NVH, a by-product of energy efficient powertrain, is conducted seriously. The NVH performance of a new type of active engine mount that offers increased advantages over a passive hydraulic mount is examined using a newly developed 6-DOF simulator. The simulator is in the shape of Hexapod Stewart Platform adopting LEMA, a new type of actuator which is patented and commercialized by ACT Inc,, the world wide leader in the design, development, and manufacture of high performance linear electro-magnetic actuators for active vibration control. The target vibration signals of an aimed vehicle at four engine mounts are measured and simulated by 6-DOF simulator at the laboratory. The resulting NVH performances of the new active mounting system at a vehicle and on a simulator are examined and compared. Even though the active mount performance of lab test demonstrates less effective than the result of a real vehicle test, vibration reduction is identified through the simulator.

• 한국소음진동공학회논문집
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• 제17권12호
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• pp.1254-1261
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• 2007

The structure has several types of noise and booming noise of a vehicle is usually caused by the vibration of the vehicle's body transmitted from the engine through the mounting system. Vector synthesis analysis is performed to predict the booming noise when the characteristic of the engine mounting system is changed., i.e., when magnitudes and phases of vibratory forces after the mounts are altered. To use this method effectively, the concept of Multi-dimensional-analysis and Experimental Design are introduced to identify the contributions of each vibration sources and transmission paths to interior noise. It was used 3inputs/1output system and found the magnitudes and phases of the forces for minimizing the noise. Finally, the synthesized interior booming noise level is predicted by the vector synthesis diagram. It is shown that the vector synthesis method can be used to obtain the optimum design characteristic of the mounting system to control the interior booming noise of a vehicle.

• 소음진동
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• 제1권1호
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• pp.39-43
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• 1991

In this study, the design concept of engine for 4WD vehicle is established by the experimental modal analysis. First, the relationships between frame and power transmission system are considered. Second, the effect of additional system (Front propeller shaft and Exhaust system) on the power transmission system is evaluated. As a result, it is desirable that of frame and power transmission system is shifted by the additional system. This is cause by the moment of inertia of the additional system, because the center of gravity location of the additional system is far from that of the power transmission system.

• 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.

• International Journal of Automotive Technology
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• 제8권6호
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• pp.731-744
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• 2007

A method for dynamic analysis and design calculation of a Powertrain Mounting System(PMS) including Hydraulic Engine Mounts(HEM) is developed with the aim of controlling powertrain motion and reducing low-frequency vibration in pitch and bounce modes. Here the pitch mode of the powertrain is defined as the mode rotating around the crankshaft of an engine for a transversely mounted powertrain. The powertrain is modeled as a rigid body connected to rigid ground by rubber mounts and/or HEMs. A mount is simplified as a three-dimensional spring with damping elements in its Local Coordinate System(LCS). The relation between force and displacement of each mount in its LCS is usually nonlinear and is simplified as piecewise linear in five ranges in this paper. An equation for estimating displacements of the powertrain center of gravity(C.G.) under static or quasi-static load is developed using Newton's second law, and an iterative algorithm is presented to calculate the displacements. Also an equation for analyzing the dynamic response of the powertrain under ground and engine shake excitations is derived using Newton's second law. Formulae for calculating reaction forces and displacements at each mount are presented. A generic PMS with four rubber mounts or two rubber mounts and two HEMs are used to validate the dynamic analysis and design calculation methods. Calculated displacements of the powertrain C.G. under static or quasi-static loads show that a powertrain motion can meet the displacement limits by properly selecting the stiffness and coordinates of the tuning points of each mount in its LCS using the calculation methods developed in this paper. Simulation results of the dynamic responses of a powertrain C.G. and the reaction forces at mounts demonstrate that resonance peaks can be reduced effectively with HEMs designed on the basis of the proposed methods.

• 한국자동차공학회논문집
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• 제10권3호
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• pp.209-217
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• 2002

This gaper discusses a multidisciplinary design optimization of the engine mounting system to improve the ride quality of a vehicle and to remove the possibility of the resonance between the powertrain system and vehicle systems. The driveline model attempts to support engine mount development by providing sufficient detail for design modification assessment in a modeling environment. Design variables used in this study are the locations, the angles and the stiffness of an engine mount system. The goal of the optimization is both decoupling the roll mode ova powertrain and minimizing the vibration transmitted to the vehicle including the powertrain, simultaneously. By applying forced vibration analysis for vehicle systems and mode decouple analysis for the engine mount system, it is shown that improved optimization result is obtained.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 추계학술대회 논문집
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• pp.351-356
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• 2009

This paper presents vibration control performance of active engine mount system installed with the magneto-rheological (MR) mount and the piezostack mount. The performance is evaluated via hardware-in-the-loop-simulation(HILS) method. As a first step, six degrees-of freedom dynamic model of an in-line four-cylinder engine which has three points mounting system is derived by considering the dynamic behaviors of MR mount and piezostack mount. As a second step, sliding mode controller(SMC) is synthesized to actively control the imposed vibration In order to demonstrate the effectiveness of the proposed active engine mount, vibration control performances are evaluated under various engine operating speeds (wide frequency range) using HILS method and presented in time and frequency domain.

• 한국소음진동공학회논문집
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• 제20권2호
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• pp.122-128
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• 2010

This paper presents vibration control performance of active engine mount system installed with the magneto-rheological(MR) mount and the piezostack mount. The performance is evaluated via hardware-in-the-loop-simulation(HILS) method. As a first step, six degrees-of freedom dynamic model of an in-line four-cylinder engine which has three point mounting system is derived by considering the dynamic behaviors of MR mount and piezostack mount. As a second step, sliding mode controller(SMC) is synthesized to actively control the imposed vibration. In order to demonstrate the effectiveness of the proposed active engine mount, vibration control performances are evaluated under various engine operating speeds(wide frequency range) using HILS method and presented in time and frequency domain.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.274-279
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• 2000

Driving of the engine makes unbalance forces which induces vibration to the engine mount system. Active vibration control must be performed to reduce the vibration and the propagation of structure-born sound. In this study, the engine system is modeled as 3-dim. vibration system including flexible structures and an effective active noise control method is proposed. Also, appropriate actuator and sensor locations and types are selected. The miniature of the engine vibration system with multi-input multi-output is built and an active vibration control with multiple filtered-X LMS algorithm is applied to it. The applied control method was effective to reduce the transmitted vibration power through the rubber mount It showed the feasibility of the control of the engine vibration systems with flexible structures.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 춘계학술대회 논문집
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• pp.444-449
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• 2009

An engine is one of the most dominant noise and vibration sources in vehicle systems. Therefore, in order to resolve noise and vibration problems due to engine, various types of engine mounts have been proposed. This work presents a new type of active engine mount system featuring a magneto-rheological (MR) fluid and a piezostack actuator. As a first step, six degrees-of freedom dynamic model of an in-line four-cylinder engine which has three points mounting system is derived by considering the dynamic behaviors of MR mount and piezostack mount. In the configuration of engine mount system, two MR mounts are installed for vibration control of roll mode motion whose energy is very high in low frequency range, while one piezostack mount is installed for vibration control of bounce and pitch mode motion whose energy is relatively high in high frequency range. As a second step, linear quadratic regulator (LQR) controller is synthesized to actively control the imposed vibration. In order to demonstrate the effectiveness of the proposed active engine mount, vibration control performances are evaluated under various engine operating speeds (wide frequency range) and presented in time domain.