자기 유변 유체를 이용한 반능동 감쇠기의 개발

정병보,권순우,김상화,박영진 한국유변학회 1999 Korea-Australia rheology journal Vol.11 No.2

감쇠기는 기계 시스템에서 에너지를 소모하는데 사용되는 요소이다. 이러한 감쇠기에는 수동 감쇠기, 능동 감쇠기, 반능동 감쇠기 등의 종류가 있다. 반능동 감쇠기는 수동 감쇠기에 비해서 더 좋은 성능을 내면서 능동 감쇠기보다는 더 작은 동력원을 필요로 하는 장치로 상황에 따라서 그 감쇠력 특성을 변화 시킬 수 있다. 본 논문은, 자기 유변 유체를 이용한 반능동 감쇠기의 개발에 관한 것이다. 자기 유변 유체는 가제어성 유체의 일종으로 인가 자기장에 대해서 그 유동학적 성질이 변하며 높은 항복응력, 낮은 점성계수, 불순물에 대한 안정성과 넓은 사용 온도 범위 등의 장점을 가진 재료이다. 이를 이용할 경우 간단한 구조로 반능동 감쇠기를 설계할 수 있을 뿐만 아니라 빠른 응답성 등의 효과도 기대할 수 있다. 본 연구에서는 자기 유변 유체를 이용하여 설계·제작된 몇 가지 종류의 감쇠기들을 통하여 그 응용 방법과 범위 그리고 응용 시 수반되는 문제점 등을 제시하였다. Dampers have been used to dissipate energy in mechanical systems. There are several types of dampers such as passive, active, and semi-active damper. Semi-active dampers have higher performance than passive ones and require less power to operate than active ones. Their damping characteristics can be changed properly for varying conditions. In this paper, we investigated the semi-active damper using Magneto-Rheological fluid. Magneto-Rheological fluid, which is one of controllable fluids, changes its damping and rheological characteristics from Newtonian fluid to Bingham fluid as the magnetic field is applied. It has several advantages such as high yield strength, low viscosity, robustness to impurities and wide temperature range of stability. If we designe a semi-active damper by using this material, we can not only design a simply structured damper but also expect rapid response. In this study, we propose several types of semi-active dampers which are designed and manufactured using Magneto-Rheological fluid and some problems encountered during their applications.

MR 댐퍼의 제어 효과 향상을 위한 Cutout 피스톤 적용에 관한 연구

김종혁(Kim, Jong-Hyuk),배재성(Bae, Jae-Sung),황재혁(Hwang, Jai-Hyuk),홍예선(Hong, Yeh-Sun) 한국소음진동공학회 2011 한국소음진동공학회 논문집 Vol.21 No.6

This paper is concerned with a study on the control effect of the MR damper using the cutout piston. The MR damper has passive damping force by the oil pressure and controllable damping force by the magnetic effect. As the velocity of the MR damper's piston increases the passive damping force increases and the ratio of the controllable damping force to the total damping force is decreased. Consequently, the control performance of the MR damper is reduced according to the increase of the velocity. In this paper, the cutout piston concept is applied to the MR damper to improve MR damper's control performance by reducing the passive damping effect. The MR damper with the cutout piston has been designed and manufactured and its hydraulic and electromagnetic analysis has been performed to predict its performance. The control performances of the MR damper with the cutout piston are verified through the comparison of experiment results and simulation results.

소형 MR 댐퍼의 모델링 및 진동제어

이종우(Lee, Jong-Woo),성민상(Seong, Min-Sang),우제관(Woo, Je-Kwan),최승복(Choi, Seung-Bok) 한국소음진동공학회 2012 한국소음진동공학회 논문집 Vol.22 No.11

This paper presents a new small-sized damper featuring magneto-rheological(MR) fluid which can be applied to vibration control system. The proposed MR damper consists of cylinder, piston, a couple of bearings, oil-seals and magnetic circuit which has two coils. In this damper, approximately 5cc of MR fluid is used. The damping force of the MR damper is designed to be followed by linear shear-mode Bingham-plastic model. In order to verify the performance of the MR damper, an experimental apparatus is established. In the experimental test, the damping force of the MR damper is measured with respect to time, displacement and velocity. In addition, the time response of MR damper is measured when 1A of step current is applied. Finally, the proposed small MR damper is applied to vibration control. In this process, a simple 1-DOF system is modeled and controlled using PID controller.

소형 MR 댐퍼의 모델링 및 진동제어

이종우(Jong-Woo Lee),성민상(Min-Sang Seong),우제관(Je-Kwan Woo),최승복(Seung-Bok Choi) 한국소음진동공학회 2012 한국소음진동공학회 학술대회논문집 Vol.2012 No.10

This paper presents a new small-sized damper featuring magneto-rheological (MR) fluid which can be applied to vibration control system. The proposed MR damper consists of cylinder, piston, a couple of bearings, oil-seals and magnetic circuit which has two coils. In this damper, approximately 5cc of MR fluid is used. The damping force of the MR damper is designed to be followed by linear shear-mode Bingham-plastic model. In order to verify the performance of the MR damper, an experimental apparatus is established. In the experimental test, the damping force of the MR damper is measured with respect to time, displacement and velocity. In addition, the time response of MR damper is measured when 1A of step current is applied. Finally, The proposed small MR damper is applied to vibration control. In this process, a simple 1-DOF system is modeled and controlled using PID controller.

MR 댐퍼의 전자기적 설계

남윤주(Yun-Joo Nam),박명관(Myeong-Kwan Park) 대한기계학회 2007 대한기계학회 춘추학술대회 Vol.2007 No.10

This paper is concerned with an electromagnetic design methodology for the magneto-rheological (MR) damper. In order to improve the performance of the MR damper, the magnetic field should be effectively supplied to the MR fluid. Therefore, it is important that magnetic circuit consisting of the MR fluid, the ferromagnetic material for magnetic flux path, and the electromagnetic coil is well designed. For this purpose, two effective approaches are proposed: one is to shorten the magnetic flux path by removing the unnecessary bulk of the yoke in order to improve the static characteristic of the MR damper, and the other is to increase the magnetic reluctance of the ferromagnetic material by minimizing its cross-sectional area through which the magnetic flux passes in order to improve the dynamic and hysteretic characteristics. The effectiveness of the proposed design methodology is verified through magnetic analysis and a series of basic experiments.

Force-Sensorless Damping Control for Damping Systems using MR Dampers

Dinh Quang Truong,Kyoung Kwan Ahn 제어로봇시스템학회 2011 제어로봇시스템학회 국제학술대회 논문집 Vol.2011 No.10

Recently, magneto-rheological (MR) fluid dampers are semi-active control devices that have begun to receive more attention. This paper presents a novel force-sensorless control method for a damping system using a MR damper. The control method is constructed by two models designed based on fuzzy-neural technique, a nonlinear black-box model (BBM) and an inverse black-box model (IBBM). By employing a fuzzy mapping system optimized by neural network technique including back-propagation and gradient descent method, the BBM model can estimate directly the damper characteristics. The inverse model, IBBM with self-learning ability, was then derived based on the BBM with the optimized parameters and neural network technique. Consequently, the designed BBM and IBBM models can be used as a ‘virtual’ force sensor and an adaptive force controller, respectively, to perform a closed-loop feedback control for any damping system which uses the corresponding MR fluid damper. Effectiveness of the proposed models for modeling as well as the force-sensorless damping control technique has been clearly verified through simulations and real-time experiments on two vibrating systems employing the same MR fluid damper series.

Modeling of a magneto-rheological (MR) fluid damper using a self tuning fuzzy mechanism

안경관,DINH QUANG TRUONG,Muhammad Aminul Islam 대한기계학회 2009 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.23 No.5

A magneto-rheological (MR) fluid damper is a semi-active control device that has recently begun to receive more attention in the vibration control community. However, the inherent nonlinear nature of the MR fluid damper makes it challenging to use this device to achieve high damping control system performance. The development of an accurate modeling method for a MR fluid damper is necessary because of its unique characteristics. Our goal was to develop an alternative method for modeling an MR fluid damper by using a self tuning fuzzy (STF) method based on neural technique. The behavior of the researched damper is directly estimated through a fuzzy mapping system. To improve the accuracy of the STF model, a back propagation and a gradient descent method are used to train online the fuzzy parameters to minimize the model error function. A series of simulations were done to validate the effectiveness of the suggested modeling method when compared with the data measured from experiments on a test rig with a researched MR fluid damper. Finally, modeling results show that the proposed STF interference system trained online by using neural technique could describe well the behavior of the MR fluid damper without need of calculation time for generating the model parameters.

Design of a Current Controller for MR CDC Dampers

이동훈(Dong Hun Lee),조봉근(Bong Geun Cho),이동락(Dong Rak Lee),부광석(Kwang Suck Boo) 한국자동차공학회 2007 한국자동차공학회 지부 학술대회 논문집 Vol.- No.-

Semi-adaptive suspension systems require that the damper should control a damping coefficient. The MR damper is suitable for the damping coefficient. In this paper, a new current control algorithm has been proposed in order to control the current provided into a coil which produces a magnetic field in the MR(Magneto-Rheological) damper. The MR(Magneto-Rheological) damper is able to control a damping coefficient of the fluid through an orifice by using the MR fluid which has a characteristic of viscosity variation according to inducted current. In general, The MR CDC(Continuous Damping Control) damper has faster reponse time than other ones. However, the MR damper has disadvantage of time delay according to input command due to very large inductance of internal coil. A new robust lead compensation control algorithm is also able to provide more robust current control

Design and modeling of energy generated magneto rheological damper

R. Ahamed,Muhammad Mahbubur Rashid,Md Meftahul Ferdaus,Hazlina Md. Yusof 한국유변학회 2016 Korea-Australia rheology journal Vol.28 No.1

In this paper an energy generated mono tube MR damper model has been developed for vehicle suspension systems. A 3D model of energy generated MR damper is developed in Solid Works electromagnetic simulator (EMS) where it is analyzed extensively by finite element method. This dynamic simulation clearly illustrates the power generation ability of the damper. Two magnetic fields are induced inside this damper. One is in the outer coil of the power generator and another is in the piston head coils. The complete magnetic isolation between these two fields is accomplished here, which can be seen in the finite element analysis. The induced magnetic flux densities, magnetic field intensities of this damper are analyzed for characterizing the damper’s power generation ability. Finally, the proposed MR damper’s energy generation ability was studied experimentally.

유체 유동 모델링에 기초한 MR댐퍼의 동적 감쇠력 예측

이종석(Jongseok Lee),백운경(Woonkyung Baek) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

This paper presents a physical model of a MR(magnetorheological) damper to predict its dynamic damping force. To predict dynamic damping force of a MR damper, it is necessary to describe the differential equation of pressure for chambers due to MR fluids compressibility. A empirical data is used to determine the valve characteristics of an annular orifice undergoing MR effect. This model can be effectively applied to the MR damper design.