Download or read book Mechanics Performance of a Novel Magneto Rheological Fluid Damper written by C. X. Liu and published by . This book was released on 2014 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The magneto-rheological (MR) fluid damper is a type of controllable fluid damper that has been employed to control the vibrations in building structures, vehicle suspensions, etc. In this paper we present an analysis of three types of working modes for MR fluid dampers, flow mode, shear mode, and extrusion mode. Further, a calculation model of the damping force in the shear flow mode is established. The design of a novel MR fluid damper, including the sealing structures, is presented, and a set of test systems was built to investigate the mechanical performance. The results provide a theoretical and experimental basis for the application of an MR fluid damper.

Download or read book A Novel Magneto rheological Fluid Damper written by Gregory Henry Hitchcock and published by . This book was released on 2002 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A New Generation of Magneto Rheological Fluid Dampers written by and published by . This book was released on 2004 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: The overall goal of this 3-year project was to study the performance of novel, fail-safe, magneto-rheological fluid (MRF) dampers by using innovative magneto-rheological (MR) materials for off-highway, high-payload vehicles such as the U.S. Army's High Mobility Multi-Purpose Wheeled Vehicle (HMMWV). In the past 3 years, significant advances were achieved in the following areas: (1) MR materials development; (2) theoretical modeling and experimental study of a new compact fail-safe MR damper, including the design and development of a full-scale prototype; (3) a full-scale experimental set up for quarter-HMMWV-models; and (4) control system development for the nonlinear MR damper system. A systematic approach was followed to unify all efforts for this integrated research. Several new MR materials were developed and characterized that could be utilized in two new MR dampers with the same overall geometric dimensions as a regular HMMWV damper. A unique full-scale experimental set up was developed and tested. Extensive investigation was conducted on an accurate control system taking into account variation of the MR fluid's base viscosity and temperature. A list of 31 publications and conference papers is included. (4 tables, 37 figures, 31 refs.).

Download or read book Insight into Magnetorheological Shock Absorbers written by Janusz Gołdasz and published by Springer. This book was released on 2014-12-27 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book deals with magnetorheological fluid theory, modeling and applications of automotive magnetorheological dampers. On the theoretical side a review of MR fluid compositions and key factors affecting the characteristics of these fluids is followed by a description of existing applications in the area of vibration isolation and flow-mode shock absorbers in particular. As a majority of existing magnetorheological devices operates in a so-called flow mode a critical review is carried out in that regard. Specifically, the authors highlight common configurations of flow-mode magnetorheological shock absorbers, or so-called MR dampers that have been considered by the automotive industry for controlled chassis applications. The authors focus on single-tube dampers utilizing a piston assembly with one coil or multiple coils and at least one annular flow channel in the piston.

Download or read book Proceedings of the 2nd International Conference on Mechanical System Dynamics written by Xiaoting Rui and published by Springer Nature. This book was released on with total page 4383 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Novel Magneto Rheological Shock Absorber for Vibration Control written by and published by . This book was released on 2001 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: This project focused on the fundamental understanding of behavior and development of novel magneto-rheological fluid (MRF) shock absorbers for mechanical systems. The aim of the study was on the feasibility of integrating controllable, semi-active, MRF shock absorbers in the suspension systems of the U.S. Army's High Mobility, Multi-purpose Wheeled Vehicle (HMMWV). New MRF damper designs were developed, fabricated and tested to meet and exceed the performance criteria set forth by the original equipment manufacture (OEM) test results. A nonlinear theoretical model was developed which can predict the performance of the MRF dampers. A unique capacity for bypass valving is included in the proposed design. A critical element of vehicle shock absorbers, bypass valving allows the shock absorber to accommodate high-force impulse loading (without failure) typical to off-highway environments. Moreover, a nonlinear fluid-mechanics based theoretical model was developed by employing Bingham plastic and Herschel-Bulkey non-Newtonian fluid models. Three dimensional electromagnetic finite element analysis was also performed for establishing a base for the MRF damper design. Extensive experiments were conducted to understand the nonlinear behavior of the new MRF dampers.

Download or read book Design and Development of a Compressible Magneto rheological Damper written by Pramod Raja and published by . This book was released on 2009 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this study is to assess the feasibility of a small-scale compressible magneto-rheological (CMR) damper for a tracked vehicle suspension system. The feature of the CMR damper combines the functions of a liquid spring and a controllable fluid damper together, which increases the mobility of these heavy vehicles while improving the stability and safety as well. The proposed CMR damper consists of a cylinder, piston-rod arrangement with an annular MR valve. The internal pressure in the chambers on either side of the piston develops the spring force. The damping force is developed when the fluid flows through the MR valve. A fluid-mechanics based model is considered to predict the behavior of the device under sinusoidal input. In addition, the non-dimensional analysis of the proposed model is presented which can be used as a tool for design analysis and scalability of the CMR dampers. The performance of the CMR damper filled with pure silicone oil and a MR fluid are studied under oscillatory vibrations for various frequencies and applied magnetic fields. Experimental results show good agreement with the theoretical predictions. The CMR damper generates a considerable spring rate and controllable damping force based on the required tracked vehicle specifications.

Download or read book Synthesis Characterization and Applications of Magneto Responsive Functional Materials written by Yancheng Li and published by Frontiers Media SA. This book was released on 2021-08-10 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book CIGOS 2019 Innovation for Sustainable Infrastructure written by Cuong Ha-Minh and published by Springer Nature. This book was released on 2019-10-10 with total page 1264 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents selected articles from the 5th International Conference on Geotechnics, Civil Engineering Works and Structures, held in Ha Noi, focusing on the theme “Innovation for Sustainable Infrastructure”, aiming to not only raise awareness of the vital importance of sustainability in infrastructure development but to also highlight the essential roles of innovation and technology in planning and building sustainable infrastructure. It provides an international platform for researchers, practitioners, policymakers and entrepreneurs to present their recent advances and to exchange knowledge and experience on various topics related to the theme of “Innovation for Sustainable Infrastructure”.

Download or read book Investigation Into the Flow Blocking Ability of a Novel Magneto Rheological Damper Unit written by R. F. Meeser and published by . This book was released on 2016 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper investigates the flow-blocking ability of a novel valve-mode magneto-rheological (MR) device to determine whether it can be used to replace the existing electro-mechanical solenoid valves that are used to control the semi-active spring characteristics in a four-state, semi-active vehicle suspension system (called the 4S4 system). MR fluids exhibit a reversible behavior that is controlled by changing the intensity of an externally applied magnetic field, allowing a change in the effective viscosity of the fluid. A mathematical model of the proposed flow-blocking valve has been developed using a combination of the quasi-Newtonian fluid model and the Bingham plastic model. This model has been modified with suitable parameters and is used to predict the blocking characteristics of the MR valve. An experimental setup has been developed with a prototype triple-pass valve mode MR fluid channel. The experimental results demonstrate that the MR valve designed and developed in this study is capable of generating a significantly high-pressure drop at very low flow rates, effectively blocking flow for practical use in the 4S4 system.

Download or read book Smart Actuation and Sensing Systems written by Giovanni Berselli and published by BoD – Books on Demand. This book was released on 2012-10-17 with total page 732 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of the present book, which tries to summarize in an edited format and in a fairly comprehensive manner, many of the recent technical research accomplishments in the area of Smart Actuators and Smart Sensors, is to combine researchers and scientists from different fields into a single virtual room. The book hence reflects the multicultural nature of the field and will allow the reader to taste and appreciate different points of view, different engineering methods and different tools that must be jointly considered when designing and realizing smart actuation and sensing systems.

Download or read book Dynamic Characterization of a Magneto rheological Fluid Damper and Synthesis of a Semi active Suspension Seat written by Xiaoqing Ma and published by . This book was released on 2006 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the point of view of suspension damper, semi-active dampers with only minimal power requirement could be applied to achieve variable damping to enhance suspension performance under complex vibration and shock environments. Magneto-rheological (MR) fluid based dampers offer significant potential for realizing semi-actively controlled variable damping with only minimal power. The MR-fluid dampers invariably exhibit considerable hysteresis, while the damping force varies with the intensity of applied electro-magnetic field and the nature of vibration in a highly nonlinear manner. A simulation model based on symmetric and asymmetric sigmoid functions is developed to fully characterize the properties of a MR-damper as function of excitation and control current. A comprehensive laboratory test program is undertaken to characterize the damping properties of a MR damper under wide ranges of excitations and control current. The essential fundamental features are identified for the modeling task, while the model parameters are identified using multi-parameter error minimization techniques. The validity of the proposed generic model is thoroughly examined by comparing the model response with the measured data under a wide range of excitations, particularly the force saturation and the hysteresis behaviour. An independent current function is further derived that could be integrated to reported regression-based hysteresis models to enhance their prediction abilities. From the results of the study, it is concluded that the refined Bouc-Wen and the proposed generalized sigmoid function model can fully characterized the nonlinear MR damping behaviour as function of applied current and excitation. A nonlinear analytical model of a pneumatic suspension seat including the motion limiting stops is developed for synthesis and analyses of the MR-damping control algorithms. The validity of the passive suspension seat model is thoroughly examined under various deterministic and random vibration excitations of varying intensities. The results suggest that attenuation of shock as well as vibration imposes difficulties design compromise of the passive damper. Owing to the strongly nonlinear properties of the suspension-seat and the MR-damper, such as hysteresis, saturation and end-stop impacts, a 'hi-lo' semi-active control algorithm is synthesized to realized modulation of the control current and thus the damping force following the skyhook control law. A continuous modulation function is further synthesized and integrated to ensure smooth transition between the 'hi' and 'lo' states. A relative position control is further introduced to limit the frequency and severity of shock motions caused by end-stop impacts. A set of performance measures is proposed to assess the characteristics of the semi-active and the resulting integrated controller under a wide range of excitations, including deterministic excitations of continuous and transient nature and random excitations of different vehicles. The potential performance benefits of the controller design are further investigated through a hardware-in-the-loop test and simulation program. The results are used to demonstrate the validity of the MR-damper and suspension seat models, and effectiveness of the control algorithm.

Download or read book Syntheses and Analyses of Semi active Control Algorithms for a Magneto rheological Damper for Vehicle Suspensions written by En Rong Wang and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design Optimization of Magneto rheological Damper with Improved Dispersion Stability written by Md Meftahul Ferdaus and published by . This book was released on 2015 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetorheological (MR) damper is one of the most advanced applications of semi active damper in controlling vibration. Due to its continuous controllability in both on and off state its practice is increasing day by day in the vehicle suspension system. MR damper's damping force can be controlled by changing the viscosity of its internal magnetorheological fluids (MRF). Still there are some problems with this damper such as MR fluid's sedimentation, optimal design configuration considering all components of the damper, power consumption and temperature rising etc. In this paper both 2-D Axisymmetric and 3-D models of MR Damper are built and finite element analysis is done widely for design optimization. Different configurations of MR damper piston, MR fluid gap, air gap and dampers housing are simulated for comparing the dampers performance variation. From the analytical results it is observed that among different configurations single coil MR damper with linear plastic air gap, top and bottom chamfered piston end and medium MR fluid gap shows better performance than other configurations by maintaining the same input current and piston velocity. Further a prototype MR fluid is developed experimentally where the carbonyl iron particles are coated with xanthan gum to reduce sedimentation and the experimental results are noticeably verifying the improved sedimentation stability. The performance of dampers' containing this new prototype MR fluid are observed by simulation models. Here the outcomes are obviously declaring damper improvement as they are delivering larger damping force compare to the MR damper with conventional fluid. In addition a power saving MR damper model has developed by finite element analysis using ANSYS software, this energy saving MR damper model is obviously showing the solution of damper's temperature rising problem. At last an experimental analysis is performed by using RD-8041-1 MR Damper. These results are compared with the optimized MR Damper's simulation results, which clearly validate the simulated results.

Download or read book Syntheses and Analyses of Semi active Control Algorithms for a Magneto rheological Damper for Vehicle Suspensions written by Enrong Wang and published by . This book was released on 2005 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vehicle suspensions impose conflicting design requirements to satisfy the performance goals related to ride, handling and road holding. Semi-active damping suspensions, with their low cost and low power requirement, have been extensively investigated to achieve better compromises among different performance measures. The magneto-rheological (MR) fluid dampers offer superior potential to achieve rapid variations in the damping force and thus the wide bandwidth. The MR dampers, however, exhibit strong nonlinearities associated with force saturation and hysteresis, which affect the force-tracking performance of the controller in an adverse manner. This dissertation research focuses on characterization and modeling of the hysteretic force-velocity (F-v) characteristics of a MR-fluid damper, and analyses of different semi-active controller syntheses to achieve improved multi-objective vehicle suspension performance. The force-limiting and hysteresis properties of a prototype MR-damper are characterized in the laboratory as functions of applied magnetic field, and response and excitation variables. An asymmetric force generation algorithm is formulated and integrated into the command current circuit to achieve asymmetric force in compression and rebound from the symmetric damper hardware. The measured data are used to identify the low-speed pre-yield, post-yield, force-limiting and hysteretic force-velocity characteristics in both symmetric as well as asymmetric damping modes. A generalized analytical model of the MR-damper is developed using symmetric and asymmetric sigmoid functions. The validity of the proposed model is demonstrated under wide ranges of control current and excitations. A number of control syntheses are formulated to achieve semi-active modulation in drive current of the MR-damper, including four different on-off and "skyhook"--Based hi-lo, and "inverse-model"-based hi-lo and sliding-mode controllers. Continuous modulation (CM) and asymmetric damping force generation (ADFG) algorithms are proposed and integrated within the control policies to minimize switching transients in the symmetric and asymmetric modes.

Download or read book Dynamic Characterization of a Magneto rheological Fluid Damper and Synthesis of a Semi active Suspension Seat written by Qing Ma Xiao and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis and testing of modified hydraulic semi active damper by magneto rheological approach written by Khedkar Yashpal Marutirao and published by Book Rivers. This book was released on 2024-02-24 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: