• International Journal of Fuzzy Logic and Intelligent Systems
• /
• 제6권1호
• /
• pp.64-69
• /
• 2006

Due to the inherent nonlinear nature of Electro-rheological (ER) fluid dampers, one of the challenging aspects for utilizing these devices to achieve high system performance is the development of accurate models and control algorithms that can take advantage of their unique characteristics. In this paper, the nonlinear damping force model is made to identify the properties of the ER damper using higher order spectrum. The higher order spectral analysis is used to investigate the nonlinear frequency coupling phenomena with the damping force signal according to the sinusoidal excitation of the damper. Also, this paper presents an inverse model of the ER damper, i.e., the model can predict the required voltage so that the ER damper can produce the desired force for the requirement of vibration control of vehicle suspension systems. The inverse model is constructed by using a multi-layer perceptron neural network. A quarter-car suspension model is considered in this paper for analysis and simulation. Simulation results show that the proposed inverse model of ER damper can obtain control voltage of ER damper for required damping force.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• 제6권3호
• /
• pp.190-196
• /
• 2006

In this paper, the nonlinear damping force model is made to identify the properties of the ER damper using higher order spectrum. The higher order spectral analysis is used to investigate the nonlinear frequency coupling phenomena with the damping force signal according to the sinusoidal excitation of the damper. Also, this paper presents an inverse model of the ER damper, i.e., the model can predict the required voltage so that the ER damper can produce the desired force for the requirement of vibration control of vehicle suspension systems. The inverse model has been constructed by using piecewise linear damping force model. In this paper, the fuzzy logic control based on heuristic knowledge is combined with the skyhook control. And it is simulated for a quarter car model. The acceleration of the sprung mass is included in the premise part of the fuzzy rules to reduce the vertical acceleration RMS value of the sprung mass. Then scaling factors and membership functions are tuned using genetic algorithm to obtain optimal performance.

• 한국생산제조학회지
• /
• 제9권5호
• /
• pp.127-134
• /
• 2000

This paper presents the development of a semi-active seat damper using MR fluids and the performance analysis of seat suspension system with a MR seat damper. An annular orifice type MR seat damper is proposed for a seat suspension of a commercial vehicle. After formulating the governing equation of motion, then an appropriate size of the seat damper is designed and manufactured. Following the evaluation of field-dependant damping force characteristics, the controllability of the damping force is experimentally demonstrated in time domain by adopting PID controller. A semi-active seat suspension with the proposed MR damper is constructed and its dynamic model is established. Subsequently, vibration control capability of the semi-active suspension system is investigated by employing the sky-hook controller.

• 한국자동차공학회논문집
• /
• 제6권6호
• /
• pp.98-106
• /
• 1998

In this study a control law and performance potential of semi-active suspensions for a tractor/semi-trailer have been investigated. The control law for airbag semi-active suspensions modeled in this study is developed using feedback linearization and Linear Quadratic (LQ) optimal control method. Inherent nonlinearity of the airbag suspensions has been considered in the control law development. It has been shown that the proposed semi-active control law provides better performance than that of well known sky-hook damping control strategy.

• 한국기계가공학회지
• /
• 제5권3호
• /
• pp.5-10
• /
• 2006

The objective of this paper is to investigate the Intelligence control characteristics of a digital damper. This paper deals with a two-degree-of-freedom suspension using the damper with ER fluid for a quarter vehicle system. The control law for semi-active suspensions modeled in this study is developed using passive and ANFIS control method. Computer simulation results show that the semi-active suspension with ER damper has good performances of ride quality.

• 한국소음진동공학회논문집
• /
• 제27권1호
• /
• pp.65-71
• /
• 2017

This work presents a comparative work on the ride comfort of a quarter car suspension system between two different magneto-rheological (MR) dampers; one is conventional type without bypass hole and the other is featured by several bypass holes in the piston. As a first step, two different MR dampers are designed on the basis of the governing equation and manufactured with same geometric dimensions except the bypass holes. After investigating the field-dependent damping properties, two dampers are installed to the quarter car suspension system. The suspension model is then derived and a sky-hook controller is implemented to identify vibration control performance under random road. It is shown that the suspension system with MR damper featured by the bypass holes can provide much better ride quality than the case without the bypass holes. This is validated via experimental implementation.

• 한국항공우주학회지
• /
• 제37권4호
• /
• pp.344-349
• /
• 2009

본 논문은 헬기용 주륜 착륙장치의 성능을 향상시킬 목적으로 반능동형 착륙장치를 도입하였다. 상용 유한요소 코드를 이용하여 자기장해석을 한 MR 댐퍼를 완충기에 적용 하였다. 착륙 거동 시 내력으로 발생되는 공기력과 감쇠력의 합을 일정하게 유지시키는 개념의 하중제어기법을 적용하여 반능동형 착륙장치의 제어기를 구성하였다. 다른 형태의 수동형 및 스카이 훅 제어 반 능동형 착륙장치와 함께 ADAMS를 이용한 낙하 시뮬레이션을 수행하였고 착륙특성에 대한 성능평가를 위해 그 결과들을 비교하였다.

• 한국소음진동공학회논문집
• /
• 제26권2호
• /
• pp.210-216
• /
• 2016

In this work, performance analysis to improve ride comfort of an ER (electrorheological) fluid damper for a mid-sized passenger vehicle in terms of tire pressure is presented. An ER damper by considering specification for a mid-sized commercial passenger vehicle is proposed and mechanically designed. After manufacturing and assembling the proposed ER damper with design parameters, their performance such as field-dependent damping forces are experimentally measured. A quarter-vehicle ER ECS (Electronic Control Suspension) system consisting of the ER damper, sprung mass, spring, sky-hook controller and tire is constructed to analysis the ride comfort performances. Vertical tire stiffness with different tire pressure is experimentally measured and investigated. In addition, ride comfort analysis such as vertical acceleration root mean square (RMS) of sprung mass is investigated under bump road using quarter-vehicle test equipment.

• 한국지능시스템학회논문지
• /
• 제17권7호
• /
• pp.875-880
• /
• 2007

자기변성유체(magnetorheological fluid)에 관한 연구는 MR 장치의 개발, MR 장치의 수학적 모델링 및 시뮬레이션, 그리고 MR 장치를 채용한 시스템의 제어 알고리즘 개발에 관한 연구로 구분된다. 시뮬레이션을 통한 제어 알고리즘 개발을 위해서는 MR 장치의 비선형 응답을 예상하기 위한 신뢰성 높은 수학적 모델이 요구된다. 또한 MR 장치 시스템을 제어하기 위해서는 제어기에서 요구하는 댐핑력을 출력하기 위한 MR 장치의 전류(또는 전압) 입력 값이 필요하며, 이 입력값을 얻기 위해서는 역댐퍼 모델이 필요하다. 이러한 이유로 MR 장치의 모델링 및 역댐퍼 모델링은 MR 장치개발의 중요한 역할을 담당하며 이에 관한 많은 연구가 요구되고 있다. 본 연구에서는 전단모드 회전형 MR 댐퍼의 모델링을 위해 개발된 MR 댐퍼를 이용하여 동특성 시험기를 제작하였으며, 전단모드 회전형 MR 댐퍼의 특성을 연구하기 위한 실험을 수행하였다. 시험기 시험결과를 통해 모델링에 필요한 시험 데이터들을 획득하였으며 다층신경망을 이용하여 전단모드 회전형 MR 댐퍼의 모델 및 역모델을 구하였다.