scholarly journals An Evaluation of Magneto Rheological Dampers for Controlling Gun Recoil Dynamics

2001 ◽  
Vol 8 (3-4) ◽  
pp. 147-155 ◽  
Author(s):  
Mehdi Ahmadian ◽  
James C. Poynor
Keyword(s):  
Closed Loop ◽  
Mr Damper ◽  
Single Shot ◽  
Test Results ◽  
Closed Loop System ◽  
Damping Force ◽  
Mr Dampers ◽  
Recoil Force ◽  
Magneto Rheological ◽  
Potential Use

The application of magneto rheological dampers for controlling recoil dynamics is examined, using a recoil demonstrator that includes a single-shot 50 caliber BMG rifle action and a MR damper. The demonstrator is selected such that it can adequately represent the velocities that commonly occur in weapons with a recoil system, and can be used for collecting data for analyzing the effects of MR dampers on recoil dynamics. The MR damper is designed so that it can work effectively at the large velocities commonly occurring in gun recoil, and also be easily adjusted to reasonably optimize the damper performance for the recoil demonstrator. The test results show that it is indeed possible to design and use MR dampers for recoil applications, which subject the damper to relative velocities far larger than the applications that such dampers have commonly been used for (i.e., vehicle applications). Further, the results indicate that the recoil force increases and the recoil stroke decreases nonlinearly with an increase in the damping force. Also of significance is the fact that the adjustability of MR dampers can be used in a closed-loop system such that the large recoil forces that commonly occur upon firing the gun are avoided and, simultaneously, the recoil stroke is reduced. This study points to the need for several areas of research including establishing the performance capabilities for MR dampers for gun recoil applications in an exact manner, and the potential use of such dampers for a fire out of battery recoil system.

Application of Magneto Rheological Dampers for Controlling Shock Loading

1999 ◽  
Author(s):  
Mehdi Ahmadian ◽  
James C. Poynor ◽  
Jason M. Gooch
Keyword(s):  
Dynamic System ◽  
Shock Loading ◽  
Closed Loop ◽  
Shock Absorber ◽  
Mr Damper ◽  
Test Results ◽  
Closed Loop System ◽  
Mr Dampers ◽  
Shock Dynamics ◽  
Magneto Rheological

Abstract This study will examine the effectiveness of magneto-rheological (MR) dampers for controlling shock dynamics. Using a system that includes a 50-caliber rifle and a magneto-rheological damper, it is experimentally shown that MR dampers can be quite effective in controlling the compromise that commonly exists between shock forces and strokes across the shock absorber mechanism. A series of tests are conducted to demonstrate that different damping forces by the MR damper can result in different shock-force/stroke profiles. The test results further show that MR dampers can be used in a closed-loop system to adjust the shock loading characteristics in a manner that fits the dynamic system constraints and requirements.

Design and Development of Magneto Rheological Dampers for Bicycle Suspensions

1999 ◽  
Author(s):  
Mehdi Ahmadian
Keyword(s):  
Dynamic Performance ◽  
Mr Damper ◽  
Test Results ◽  
Design And Development ◽  
Damping Force ◽  
Mr Fluid ◽  
Performance Improvements ◽  
Mr Dampers ◽  
Force Velocity ◽  
Magneto Rheological

Abstract The design and fabrication of a magneto rheological (MR) damper for bicycle suspension applications is addressed. Two 1998 Judy® Dampers are retrofitted with MR valves, to achieve the damping force adjustability that the MR fluid offers. One design attempts to use as many of the Judy® Damper components as possible. The second design significantly modifies the Judy® Damper, to better accommodate the MR valve and ease of fabrication and assembly, although fitting into the same envelope as the Judy® damper for a direct retrofit. The two MR dampers are fabricated and assembled for force-velocity characterization testing. The test results show that properly-designed MR dampers can provide significant dynamic performance improvements, as compared to conventional passive bicycle dampers.

Passenger Comfort Analysis in an Automotive Considering a Magneto-Rheological Damper based Suspension

2017 ◽  
Vol 8 (4) ◽  
Author(s):  
R.B. Soujanya ◽  
D.D. Jebaseelan ◽  
S. Kannan
Keyword(s):  
Ride Comfort ◽  
Mr Damper ◽  
Nonlinear Behaviour ◽  
Passive Damping ◽  
Damping Force ◽  
The Road ◽  
Mr Dampers ◽  
Moving Vehicles ◽  
Magneto Rheological ◽  
Multi Body

Passenger’s comfort in moving vehicles depends on the quality of the ride. The major cause of discomfort is the vibration transmitted to passengers due to the road irregularities. For a comfortable ride on a vehicle, vibration must stay within prescribed standards. In the present work, an attempt was made to show that, the vibrations can be limited with the use of Magneto-rheological (MR) dampers for varying road profiles than the passive damping methods. MR dampers are semi-active control devices that use MR fluids to produce controllable damping force as they are known to exhibit nonlinear behaviour. Multi body dynamic studies were done to study the response of the system using a quarter car model. In this paper, passive damping (viscous damping) was considered at natural frequency of 1.012Hz, the response of damping was observed after 10s and the acceleration was found to be 6m/s2. When MR damper is employed as the magnetic force increases, the response of the damping was better than the passive damping, at 1.2A it comes down to 0.55m/s2, and the vibration gets dampened after 1.75s. Hence, from this study it is concluded that the MR damper can be employed in automobile for better ride comfort.

Semi-Active Control of a Vehicle Suspension Based on Magneto-Rheological Damper

2011 ◽  
Vol 311-313 ◽  
pp. 2286-2290
Author(s):  
Jie Lai Chen ◽  
Xue Zheng Jiang ◽  
Ning Xu
Keyword(s):  
Ride Comfort ◽  
Mr Damper ◽  
Vehicle Suspension ◽  
Damping Force ◽  
Mr Dampers ◽  
Quarter Car ◽  
Set Up ◽  
Magneto Rheological ◽  
Two Degree Of Freedom ◽  
The Magnetic Field

The focus of this study is to experimentally investigate a semi-active magneto-rheological (MR) damper for a passenger vehicle, by using a quarter car models. After verifying that the damping force of the MR damper can be continuously tuned by the intensity of the magnetic field, a full-scale two-degree of freedom quarter car experimental set up is constructed to study the vehicle suspension. On-off skyhook controller is employed to achieve the desired damping force. The experimental results show that the semi-active vehicle suspension vibration control system based on MR dampers is feasible and can effectively improve ride comfort of vehicle.

Design and Analysis of Magneto-Rheological Dampers under Impact Loads

2013 ◽  
Vol 295-298 ◽  
pp. 2045-2048
Author(s):  
Xiao Ming Han ◽  
Yu Cheng Bo ◽  
Qiang Li ◽  
Ji Huang
Keyword(s):  
Control Strategy ◽  
Test Bench ◽  
Mr Damper ◽  
Second Law ◽  
Impact Loads ◽  
Structure Parameter ◽  
Mr Dampers ◽  
Recoil Force ◽  
Magneto Rheological ◽  
And Control

In order to improve recoil mechanism’s buffering function of automatic weapon, using Newton’s second law, its recoil movement is analyzed and design model of magneto-rheological (MR) damper under impact loads is built. Structure parameter and control strategy are defined. Dampers’ characteristic curves at different magnetizing currents and different recoil speeds are tested on a damper indicator test bench. Some weapon’s recoil forces are artificially computed. The research results indicate that MR dampers have a perfect damping plateau effect. Recoil force of automatic weapon will be reduced by a big margin using the property that MR fluid can change at applied magnetic to control damping rules.

Effective Test Procedures for Evaluating Force Characteristics of Magneto-Rheological Dampers

2003 ◽  
Author(s):  
Mehdi Ahmadian ◽  
James C. Poynor
Keyword(s):  
Relative Velocity ◽  
Test Procedure ◽  
Mr Damper ◽  
Electrical Current ◽  
Test Results ◽  
Test Procedures ◽  
Vehicle Suspensions ◽  
Mr Dampers ◽  
Magneto Rheological ◽  
Force Characteristics

This paper will provide a new test procedure for determining the force characteristics of magneto rheological (MR) dampers that are commonly used for vehicle suspensions. Force characteristics of a damper, in this case, refers to establishing the amount of force that the damper can provide at different relative velocities across the two ends of the damper, Force characteristics of a damper, which are commonly presented as a plot of force versus relative velocity—commonly known as force-velocity curve—are established in a shock (or damper) dynamometer in which one end of the damper is kept fixed and the other end is moved in a cyclical manner at a prescribed displacement and frequency. The peak damper force at each velocity is measured and plotted as discrete data points versus relative velocity across the damper. This is a well-understood and commonly used procedure for passive shock absorbers or dampers. For magneto rheological dampers, however, our study shows that such procedures do not necessarily provide an accurate assessment of the force characteristics of MR dampers in all damping conditions. The damping condition of MR dampers can be changed by a small amount of electrical current that can be provided to the damper. The inaccuracies are mainly due to the changing dynamics of the MR fluid inside the damper at different damping conditions. This paper will provide the test results for a MR damper, using the new and the conventional test procedures. The test results indicate that the use of the new test procedure will procedure will allow for an accurate representation of the MR damper force at all velocities, within the range of the currents that the damper is designed for.

Damping characteristics of a magneto-rheological damper with dual independent controllable ducts

2021 ◽  
pp. 1045389X2110188
Author(s):  
Jianqiang Yu ◽  
Xiaomin Dong ◽  
Tao Wang ◽  
Zhengmu Zhou ◽  
Yaqin Zhou
Keyword(s):  
Dynamic Range ◽  
Fluid Flows ◽  
Mr Damper ◽  
Viscous Damping ◽  
The Novel ◽  
The Finite Element Method ◽  
Damping Force ◽  
Damping Characteristics ◽  
Magneto Rheological ◽  
The Mathematical Model

This paper presents the damping characteristics of a linear magneto-rheological (MR) damper with dual controllable ducts based on numerical and experimental analysis. The novel MR damper consisting of a dual-rod cylinder system and a MR valve is used to reduce the influences of viscous damping force and improve dynamic range. Driven by the dual-rod cylinder system, MR fluid flows in the MR valve. The pressure drop of the MR valve with dual independent controllable ducts can be controlled by tuning the current of two independent coils. Based on the mathematical model and the finite element method, the damping characteristics of the MR damper is simulated. A prototype is designed and tested on MTS machine to evaluate its damping characteristics. The results show that the working states and damping force of the MR damper can be controlled by the two independent coils.

A Reliability Assessment Model for MR Damper Components within a Smart Structural Control Scheme

2008 ◽  
Vol 56 ◽  
pp. 218-224
Author(s):  
Maguid H.M. Hassan
Keyword(s):  
Structural Control ◽  
Inverse Dynamics ◽  
Mr Damper ◽  
Assessment Model ◽  
Resistance Force ◽  
Mr Dampers ◽  
Control Scheme ◽  
Smart Control ◽  
Control Devices ◽  
Magneto Rheological

Smart control devices have gained a wide interest in the seismic research community in recent years. Such interest is triggered by the fact that these devices are capable of adjusting their characteristics and/or properties in order to counter act adverse effects. Magneto-Rheological (MR) dampers have emerged as one of a range of promising smart control devices, being considered for seismic applications. However, the reliability of such devices, as a component within a smart structural control scheme, still pause a viable question. In this paper, the reliability of MR dampers, employed as devices within a smart structural control system, is investigated. An integrated smart control setup is proposed for that purpose. The system comprises a smart controller, which employs a single MR damper to improve the seismic response of a single-degree-of-freedom system. The smart controller, in addition to, a model of the MR damper, is utilized in estimating the damper resistance force available to the system. On the other hand, an inverse dynamics model is utilized in evaluating the required damper resistance force necessary to maintain a predefined displacement pattern. The required and supplied forces are, then, utilized in evaluating the reliability of the MR damper. This is the first in a series of studies that aim to explore the effect of other smart control techniques such as, neural networks and neuro fuzzy controllers, on the reliability of MR dampers.

Nonlinear Control of Semi-Active MacPherson Suspension System

2012 ◽  
Author(s):  
Olugbenga M. Anubi ◽  
Carl D. Crane
Keyword(s):  
Closed Loop ◽  
Control Design ◽  
Mr Damper ◽  
Suspension System ◽  
Time Domain Simulation ◽  
Closed Loop System ◽  
Output Feedback Controller ◽  
Space Frequency ◽  
Simulation Results ◽  
Active Damper

This paper presents the control design and analysis of a non-linear model of a MacPherson suspension system equipped with a magnetorheological (MR) damper. The model suspension considered incorporates the kinematics of the suspension linkages. An output feedback controller is developed using an ℒ2-gain analysis based on the concept of energy dissipation. The controller is effectively a smooth saturated PID. The performance of the closed-loop system is compared with a purely passive MacPherson suspension system and a semi-active damper, whose damping coefficient is tunned by a Skyhook-Acceleration Driven Damping (SH-ADD) method. Simulation results show that the developed controller outperforms the passive case at both the rattle space, tire hop frequencies and the SH-ADD at tire hop frequency while showing a close performance to the SH-ADD at the rattle space frequency. Time domain simulation results confirmed that the control strategy satisfies the dissipative constraint.

A Non Parametric Model for Magneto Rheological Dampers

1999 ◽  
Author(s):  
Mehdi Ahmadian ◽  
Xubin Song
Keyword(s):  
Test Data ◽  
Mr Damper ◽  
Parametric Model ◽  
Parametric Models ◽  
Magnetic Saturation ◽  
Mr Dampers ◽  
Electro Magnetic ◽  
Magneto Rheological ◽  
Force Characteristics ◽  
Non Parametric

Abstract A non-parametric model for magneto-rheological (MR) dampers is presented. After discussing the merits of parametric and non-parametric models for MR dampers, the test data for a MR damper is used to develop a non-parametric model. The results of the model are compared with the test data to illustrate the accuracy of the model. The comparison shows that the non-parametric model is able to accurately predict the damper force characteristics, including the damper non-linearity and electro-magnetic saturation. It is further shown that the parametric model can be numerically solved more efficiently than the parametric models.

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