Experimental Verification of Controllability of a Mixed Mode MR Fluid Mount

2011 ◽  
Author(s):  
Shuo Wang ◽  
Mohammad Elahinia ◽  
The Nguyen
Keyword(s):  
Mixed Mode ◽  
Alternative Energy ◽  
Vibration Isolation ◽  
Dynamic Stiffness ◽  
Hybrid Vehicles ◽  
Flow Mode ◽  
Shear Mode ◽  
Mr Fluid ◽  
Set Up ◽  
Different Levels

With the advent of alternative energy and hybrid vehicles come new vibration problems and challenges that require nontraditional solutions. Semi-active vibration isolation devices are preferred to address the problem due to their effectiveness and affordability. A magnetorheological (MR) fluid mount can provide effective vibration isolation for applications such as hybrid vehicles. The MR fluid can produce different levels of damping when exposed to different levels of magnetic field. The fluid can be working in three modes which are the flow mode, shear mode and squeeze mode. A mixed mode MR fluid mount was designed to operate in a combination of the flow mode and the squeeze mode. Each of the working modes and the combined working mode has been studied. The mount’s performance has been verified in simulation and experiments. Based on the simulation and experimental results, it can be seen that the mount can provide a large range of dynamic stiffness. Given this range of dynamic stiffness, a controller has been designed to achieve certain dynamic stiffness at certain frequencies. The experiments are set up to realize the hardware-in-the-loop tests. Results from the experiments show that the mixed mode MR fluid mount is able to achieve desired dynamic stiffness which is directly related to vibration transmissibility.

scholarly journals Displacement and Force Control of a Quarter Car Using a Mixed Mode MR Mount

2013 ◽  
Vol 20 (1) ◽  
pp. 1-17 ◽  
Author(s):  
Shuo Wang ◽  
Mohammad Elahinia ◽  
The Nguyen
Keyword(s):  
Mixed Mode ◽  
Fuzzy Logic Controller ◽  
Dynamic Stiffness ◽  
Motor Units ◽  
Flow Mode ◽  
Control Force ◽  
Mr Fluid ◽  
Hydraulic Hybrid ◽  
Quarter Car ◽  
Set Up

In hydraulic hybrid vehicles (HHV), vibration in dual-mode pump/motor units should be isolated from the chassis. A mixed mode magnetorheological (MR) fluid mount was adopted to isolate this vibration and was evaluated in a quarter car model. The MR fluid mount was designed to be able to operate in flow mode and squeeze mode independently and simultaneously. For HHVs, it is desirable to control force and displacement transmissibility. These simulation results presented a basis for designing an effective algorithm to control both the displacement transmissibility and force transmissibility. Moreover, a hierarchical controller for minimizing the two requirements for transmissibility was also constructed. At last, a fuzzy logic controller was devised to closely reproduce the effect of the hierarchical controller. The experiments were set up to facilitate the hardware-in-the-loop evaluation of the mount. Results from the experiments showed that the mixed mode MR fluid mount was able to achieve desired dynamic stiffness profile to minimize the dual-transmissibility criterion.

Performance of an Adaptive Magnetorheological Fluid Mount

2007 ◽  
Author(s):  
Constantin Ciocanel ◽  
The Nguyen ◽  
Christopher Schroeder ◽  
Mohammad H. Elahinia
Keyword(s):  
Vibration Isolation ◽  
Dynamic Stiffness ◽  
Magnetorheological Fluid ◽  
Flow Mode ◽  
Frequency Range ◽  
Governing Equations ◽  
Mr Fluid ◽  
System Parameters ◽  
Force Transmissibility ◽  
Working Frequency

The paper investigates the response of a magnetorheological (MR) fluid based mount that combines the squeeze and flow modes in operation. The mount governing equations are introduced and the effect of system parameters on its performance is analyzed. The proposed design yields a high static and a low dynamic stiffness in the working frequency range of the mount. The overall vibration isolation characteristic of the mount is enhanced if compared to that of existing hydraulic mounts. Displacement and/or force transmissibility can be isolated or significantly reduced, in real time, by controlling the MR fluid yield stress. An embedded electromagnet is used to activate the MR fluid that can work in either squeeze or flow modes, or in both simultaneously. The results indicate that the flow mode is less effective in reducing transmissibility than the squeeze mode. However, when the flow and squeeze modes are both activated, the effect of the flow mode becomes more obvious.

Dynamic characteristics of squeeze-type mount using magnetorheological fluid

2005 ◽  
Vol 219 (1) ◽  
pp. 27-34 ◽  
Author(s):  
Y K Ahn ◽  
J-Y Ha ◽  
Y-H Kim ◽  
B-S Yang ◽  
M Ahmadian ◽  
...  
Keyword(s):  
Dynamic Characteristics ◽  
Experimental Analysis ◽  
Vibration Isolation ◽  
Dynamic Behaviour ◽  
Electrical Current ◽  
Magnetorheological Fluid ◽  
Test Set ◽  
Mr Fluid ◽  
Set Up ◽  
Stiffness And Damping

This paper presents an analytical and experimental analysis of the characteristics of a squeeze-type magnetorheological (MR) mount which can be used for various vibration isolation areas. The concept of the squeeze-type mount and details of the design of a squeeze-type MR mount are discussed. These are followed by a detailed description of the test set-up for evaluating the dynamic behaviour of the mount. A series of tests was conducted on the prototype mount built for this study, in order to characterize the changes occurring as a result of changing electrical current to the mount. The results of this study show that increasing electrical current to the mount, which increases the yield stress of the MR fluid, will result in an increase in both stiffness and damping of the mount. The results also show that the mount hysteresis increases with increase in current to the MR fluid, causing changes in stiffness and damping at different input frequencies.

Effect of Internal Pressure on Flow Properties of Magnetorheological Fluids

2011 ◽  
Author(s):  
Andrea Spaggiari ◽  
Eugenio Dragoni
Keyword(s):  
Internal Pressure ◽  
System Design ◽  
Flow Mode ◽  
Shear Mode ◽  
Mr Fluid ◽  
Mr Fluids ◽  
Experimental Apparatus ◽  
Gear Pumps ◽  
Strengthen Effect ◽  
Hydraulic System Design

Magnetorheological (MR) fluids have a lot of applications in the industrial world, but sometimes their properties are not performing enough to meet system requirements. It has been found that in shear mode MR fluids exhibits a pressure dependency called squeeze strengthen effect. Since a lot of MR fluid based devices work in flow mode (i.e. dampers) this paper investigates the behaviour in flow mode under pressure. The system design is articulated in three steps: hydraulic system design, magnetic circuit design and design of experiment. The experimental apparatus is a cylinder in which a translating piston displaces the fluid without the use of standard gear pumps, incompatible with MR fluids. The experimental apparatus measures the MR fluid yield stress as a function of pressure and magnetic field allowing the yield shear stress to be calculated. A statistical analysis of the results shows that the squeeze strengthen effect is present in flow mode as well and the presence of internal pressure is able to enhance the performance of MR fluid by nearly ten times.

Effect of Pressure on the Flow Properties of Magnetorheological Fluids

2012 ◽  
Vol 134 (9) ◽  
Author(s):  
A. Spaggiari ◽  
E. Dragoni
Keyword(s):  
Flow Mode ◽  
Shear Mode ◽  
Mr Fluid ◽  
Mr Fluids ◽  
Pressure Dependency ◽  
Experimental Apparatus ◽  
Experiment Method ◽  
Gear Pumps ◽  
Strengthen Effect ◽  
System Requirements

Magnetorheological (MR) fluids are widely used in the industrial world; however, sometimes their properties fail to meet system requirements. In shear mode, MR fluids have been found to exhibit a pressure dependency called squeeze strengthen effect. Since a lot of MR fluid based devices work in flow mode (i.e., dampers), this paper investigates the behavior in flow mode under pressure. The system design consists of three steps: the hydraulic system, the magnetic circuit, and the design of experiment method. The experimental apparatus is a cylinder in which a piston displaces the fluid without the use of standard gear pumps, which are incompatible with MR fluids. The experimental apparatus measures the yield stress of the MR fluid as a function of the pressure and magnetic field, thus, enabling the yield shear stress to be calculated. A statistical analysis of the results shows that the squeeze strengthen effect is also present in flow mode, and that the internal pressure enhances the performance of MR fluids by nearly five times.

A Squeeze-Flow Mode Magnetorheological Mount: Design, Modeling, and Experimental Evaluation

2012 ◽  
Vol 134 (2) ◽  
Author(s):  
T. M. Nguyen ◽  
C. Ciocanel ◽  
M. H. Elahinia
Keyword(s):  
Vibration Isolation ◽  
Magnetic Circuit ◽  
Dynamic Stiffness ◽  
Experimental Results ◽  
Squeeze Flow ◽  
Design Parameters ◽  
Flow Mode ◽  
Wide Range ◽  
Isolation Device ◽  
Stiffness And Damping

This paper presents a dual-mode magnetorheological (MR) fluid mount. Combining the fluid’s flow and squeeze modes of operation gives this MR mount a unique possibility for varying dynamic stiffness and damping. Details on the design of the internal structure of the mount and the magnetic circuit are provided. Simulation and experimental results are presented to show the effectiveness of the magnetic circuit. A mathematical model that combines the behavior of the fluid and the elastomeric parts and takes into account the magnetic activation of the fluid is used to gauge the effect of design parameters on the isolation characteristics of the mount. Experimental results show that in the proposed design, the dynamic stiffness of the mount may be varied over a wide range of frequencies making the mount a unique and versatile vibration isolation device for cases where input excitation occurs over a wide range of frequencies.

Skyhook Control of a Mixed Mode Magnetorheological Fluid Mount

2010 ◽  
Author(s):  
Shuo Wang ◽  
The Nguyen ◽  
Walter Anderson ◽  
Constantin Ciocanel ◽  
Mohammad Elahinia
Keyword(s):  
Mixed Mode ◽  
Magnetorheological Fluid ◽  
Resonance Peak ◽  
Control Algorithms ◽  
Flow Mode ◽  
Frequency Range ◽  
Mr Fluid ◽  
Working Frequency ◽  
Fluid Dampers ◽  
Mr Effect

Magnetorheological (MR) fluid mounts have their own advantages over the hydraulic mounts because they can provide extra damping and stiffness due to the MR effect. Many papers contribute to the control of MR fluid dampers, while very few papers focus on the control of MR mounts. This paper investigated skyhook control for a mixed mode MR fluid mount. The MR fluid mount can operate in two working modes: flow mode and squeeze mode. The skyhook control algorithms were developed and studied for the flow mode and squeeze mode separately and simultaneously. Simulation results show that the skyhook control can significantly reduce the resonance peak and achieve the lowest transmissibility in the whole working frequency range of the mount. When flow mode and squeeze mode are activated and controlled at the same time, the effect of squeeze mode is more obvious than that of the flow mode.

scholarly journals Dynamic characterization of controlled multi-channel semi-active magnetorheological fluid mount

2021 ◽  
Vol 12 (2) ◽  
pp. 751-764
Author(s):  
Zhihong Lin ◽  
Mingzhong Wu
Keyword(s):  
High Frequency ◽  
Optimization Design ◽  
Vibration Isolation ◽  
Dynamic Stiffness ◽  
Low Frequency ◽  
Vehicle Model ◽  
Mr Fluid ◽  
Unbalanced Force ◽  
Low Frequency Vibration ◽  
Engine Mount

Abstract. In this paper, a novel structure of a controlled multi-channel semi-active magnetorheological (MR) fluid mount is proposed, including four controlled channels and one rate-dip channel. Firstly, the magnetic circuit analysis, rate-dip channel optimization design, and MR fluid mount damping analysis are given. Secondly, the mathematical model of the controlled multi-channel semi-active MR fluid mount is constructed. We analyze the effect of controlled multi-channel closing on the dynamic characteristics of the mounts and the effect of the presence or absence of the rate-dip channel on the low-frequency isolation of the mount. Finally, the controlled multi-channel semi-active MR fluid mount was applied to the 1/4 vehicle model (a model consisting of an engine, a single engine mount, a single suspension and a vehicle frame), with the transmissibility of the engine relative to the vehicle frame at low frequency and the transmissibility of the engine reciprocating unbalanced force to the vehicle frame magnitude at high frequency as the evaluation index. Numerical simulation shows the following points. (1) The controllable multi-channel semi-active MR fluid mount can achieve adjustable dynamic stiffness and damping with applied 2 A current to different channels. (2) With known external excitation source, applied currents to different controllable channels can achieve the minimum transmissibility and meet the mount wide-frequency vibration isolation requirement, while adding a rate-dip channel can improve the low-frequency vibration isolation performance of the MR fluid mount. (3) Switching and closing different controllable channels in the 1/4 vehicle model can achieve the minimum transmissibility of low-frequency engine vibrations relative to the vehicle frame and high-frequency engine vibrations reciprocating an unbalanced force to the vehicle frame. Therefore, the design of the controllable multi-channel semi-active MR fluid mount can meet the wide-frequency isolation.

A Preliminary Parametric Study of Electrorheological Dampers

1994 ◽  
Vol 116 (3) ◽  
pp. 570-576 ◽  
Author(s):  
Z. Lou ◽  
R. D. Ervin ◽  
F. E. Filisko
Keyword(s):  
Cross Section ◽  
Mixed Mode ◽  
Flow Mode ◽  
Shear Mode ◽  
Zero Field ◽  
Damping Force ◽  
Bingham Plastic ◽  
Control Effectiveness ◽  
Er Damper ◽  
Er Fluid

In approaching the design of an electrorheology-based, semi-active suspension, the electrorheological component (ER damper) can be built as either a flow-mode, shear-mode, or mixed-mode type of damper. The source of damping force in the flow-mode is exclusively from flow-induced pressure drop across a valve, while that in the shear-mode is purely from the shear stress on a sliding surface. The dynamics of the fluid flow are included in the derivation of the zero-field damping forces. The control effectiveness is found to be strongly related to the dynamic constant (which is proportional to the square root of the vibration frequency) and, for shear-and flow-mode dampers, the ratio of the piston area to the cross-section of the ER control gap. To achieve the same performance, a flow-mode ER damper is not as compact and efficient as a shear-mode ER damper. With the same ER damping force, a mixed-mode damper is more compact than a shear-mode damper. However, the mixed-mode damper does not have as a low zero-field damping force as the shear-mode damper. The analysis is based on the assumption that the ER fluid is Bingham plastic.

NONDIMENSIONAL QUASISTEADY ANALYSIS OF A MAGNETORHEOLOGICAL DASHPOT DAMPER

2005 ◽  
Vol 19 (07n09) ◽  
pp. 1584-1590 ◽  
Author(s):  
YOUNG-TAI CHOI ◽  
NORMAN M. WERELEY
Keyword(s):  
Mixed Mode ◽  
Performance Metrics ◽  
Fluid Velocity ◽  
Hydraulic Cylinder ◽  
Flow Mode ◽  
Damping Capacity ◽  
Shear Mode ◽  
Stress Profile ◽  
Cylinder Wall ◽  
Bingham Plastic

This paper addresses nondimensional analysis of a magnetorheological (MR) dashpot damper. An MR dashpot damper consists of a loosely fitting piston within a hydraulic cylinder or reservoir of MR fluids. The fluid flow within such a damper presents both Poiseuille (flow mode or pressurized flow through the duct) and Couette (shear mode or shear flow due to relative motion between piston and hydraulic cylinder wall) simultaneously. Thus, an MR dashpot damper, which mixes both shear and flow modes of behavior, is called a mixed mode damper. In this study, a quasi-steady analysis of MR dashpot dampers was revisited based on the utilization of the Bingham-plastic constitutive model to assess performance metrics such as damping capacity. For the mixed mode MR damper, key physical quantities are derived: fluid velocity profile, shear stress profile, and damping coefficient. In addition, the plug thickness equation to characterize the relationship between the Bingham number and the plug thickness is constructed. Through computer simulation, damping characteristics of the mixed mode MR dashpot damper are evaluated and compared to the flow mode case.

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