Download or read book A Novel Magnetorheological Fluid elastomer Vibration Isolator written by David J. York and published by . This book was released on 2007 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Novel Semi active Magnetorheological Mount for Vibration Isolation written by The Minh Nguyen and published by . This book was released on 2009 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years, the higher price of fossil fuels and green house effects has been the motivating factors for the automotive industry to introduce more efficient vehicles. Today evolution in automobiles is mostly to reduce fuel consumption and emissions. Variable cylinder management has been employed in V6 & V8 engines to allow the vehicles to operate with only 3 or 4 active cylinders. Hybrid technologies including hybrid electric and emerging hydraulic hybrid equip the vehicles with additional power sources which work at higher efficiency than that of internal combustion engines. The proven advantages of the hybrid vehicles or variable cylinder management also come with challenging problem of noise, vibration and harshness (NVH). This issue has to be properly addressed in order for the technologies to find consumer acceptance. The NVH in modern vehicles is mainly due to the involvement of multiple power sources working in different modes and the switching among them. This feature can lead to shock and vibration over a wide range of frequencies. It has been proven that passive vibration isolators, e.g. elastomeric and hydraulic, are not sufficient to deal with this problem. Active mounts are effective, but they are expensive and can lead to stability problems. Research has shown that semi-active vibration isolators are as effective as active mounts while being significantly less expensive. In this study, a novel shock and vibration isolator in the form of a magnetorheological (MR) mount is introduced. MR fluids are smart fluids which respond to magnetic fields. Using these fluids it is possible to transform a passive hydraulic vibration isolator to a semi-active device one. The semi-active MR mount presented in this dissertation is unique because it utilizes the MR fluid in two configurations flow (or valve) and squeeze modes to mitigate shock and vibration over a wide range of frequencies. The new mount was designed following a thorough literature review of the semi-active and MR vibration isolation. A mathematical model of the mount was developed to represent the vibration isolation behavior of the system. The analytical model was numerically solved and simulated in MATLAB®. Simulation results were used to predict the performance of the mount and to evaluate the effect of design parameters on the mount behavior. A prototype MR mount was built based on the analytical model. The mount was experimentally evaluated. The experimental data was used to verify the model in predicting the mount characteristics. This study provided a fundamental understanding on the behavior of MR fluid in vibration isolation devices. The mount demonstrates effectiveness of the flow and squeeze modes when they are activated individually and in combination. The results of this research can lead to developing effective isolation devices for many different applications including hybrid and alternative fuel vehicles.
Download or read book Design and Control of a Vibration Isolator Using a Biased Magnetorheological Elastomer written by Saul Opie and published by . This book was released on 2008 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electrorheological Fluids And Magnetorheological Suspensions Proceedings Of The 10th International Conference On Ermr 2006 written by Faramarz Gordaninejad and published by World Scientific. This book was released on 2007-10-17 with total page 843 pages. Available in PDF, EPUB and Kindle. Book excerpt: ERMR 2006 included invited speakers, technical presentations, poster presentations, and a student paper competition. At the conference banquet, Dr. David Carlson of Lord Corporation addressed the conference attendees and gave a stirring speech on the history of ER and MR fluids, as well as current and future applications. A unique feature of the ERMR Conferences is that they comprehensively cover issues ranging from physics to chemistry to engineering applications of ER and MR materials held in a general session to enhance the interaction between the scientists and engineers. The sessions in ERMR 2006 were organized based into two Symposia: a) Materials and b) Applications. Topics covered in the Materials Symposium included: mechanisms, preparation, and characterization of ER and MR materials. Topics covered in the Applications Symposium included: ER and MR devices, control systems, system integration, and applications. This structure was implemented in order to enable interaction between attending scientists and engineers in both the Materials Symposium and the Applications Symposium, and to enhance the free flow of ideas, and the potential collaborative research opportunities.
Download or read book Fabrication Characterization and Control of a Novel Magnetorheological Elastomer based Adaptive Tuned Vibration Absorber written by Armin Rasooli and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semi-active tunable vibration absorbers (SATVAs) have recently received growing interest due to their energy efficiency, simple structure and optimal performance under a wide frequency-bandwidth. SATVAs generally consist of elements with variable stiffness to allow for optimal performance under a wide frequency range compared with their passive analogues which are typically tuned at a particular frequency. Magnetorheological elastomers (MREs) are unique smart materials which can serve as the variable-stiffness elements in SATVAs. MREs are basically the solid state of the well-known magnetorheological (MR) fluids, which in contrast to MR fluids, their stiffness (storage modulus) can be continuously changed rapidly through the application of an external magnetic field. The present research study is concerned with the modeling, fabrication and control of a novel SATVA based on MRE-filled sandwich structures. To this end, a novel five-layered beam-shape sandwich structure was designed using MREs as core layers, reinforced with thin elastic plates on top, middle and bottom. To provide for a suitable and controllable magnetic field a set of U-shaped electromagnets were also designed. A specific two-node adaptive sandwich beam element has been developed to derive the governing dynamic equations of the MRE-based sandwich beam in the finite element (FE) form. The developed finite element model of the MRE-based sandwich beam together with the developed magnetic finite element of the electromagnets have then been effectively utilized to identify the suitable design parameters for the proposed SATVA to meet the geometrical and mechanical requirements. Experimental tests have been designed to acquire the magnetic permeability and the storage modulus of the fabricated MREs required for the modeling. Next the proposed SATVA was fabricated and subsequently tested using an electrodynamic shaker to evaluate its vibration performance and also to validate the developed FE models. The results indicate that the fabricated SATVA, provides an approximately 9% shift in the natural frequency. The validated FE models were subsequently utilized to conduct systematic sensitivity analysis to investigate the effect of different design parameters including the thickness of elastic layers and the position of electromagnets. The experimental results were also used to developed an equivalent lumped mass model for the proposed SATVA. Finally, a phased-based control strategy using the full-state adaptive Kalman filter (AKF) observer has been developed to adaptively tune the natural frequency of the absorber to the varying excitation conditions. It is expected that the present research dissertation provides an essential guidance for the future development of light-weight adaptive vibration absorbers.
Download or read book Magnetorheology written by Norman Wereley and published by Royal Society of Chemistry. This book was released on 2014 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt: Leading experts provide a timely overview of the key developments in the physics, chemistry and uses of magnetorheological fluids.
Download or read book Magnetorheological Fluid Foam Vibration Isolation System for Nanosats written by Israel López Martínez and published by . This book was released on 2004 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the 10th International Conference on Electrorheological Fluids and Magnetorheological Suspensions written by Faramarz Gordaninejad and published by World Scientific. This book was released on 2007 with total page 843 pages. Available in PDF, EPUB and Kindle. Book excerpt: ERMR 2006 included invited speakers, technical presentations, poster presentations, and a student paper competition. At the conference banquet, Dr. David Carlson of Lord Corporation addressed the conference attendees and gave a stirring speech on the history of ER and MR fluids, as well as current and future applications. A unique feature of the ERMR Conferences is that they comprehensively cover issues ranging from physics to chemistry to engineering applications of ER and MR materials held in a general session to enhance the interaction between the scientists and engineers. The sessions in ERMR 2006 were organized based into two Symposia: a) Materials and b) Applications. Topics covered in the Materials Symposium included: mechanisms, preparation, and characterization of ER and MR materials. Topics covered in the Applications Symposium included: ER and MR devices, control systems, system integration, and applications. This structure was implemented in order to enable interaction between attending scientists and engineers in both the Materials Symposium and the Applications Symposium, and to enhance the free flow of ideas, and the potential collaborative research opportunities.
Download or read book Comprehensive Investigation on Active Passive Hybrid Isolation and Tunable Dynamic Vibration Absorption written by Fei Wang and published by Springer. This book was released on 2018-12-17 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses efforts to control the low-frequency vibration transmission of typical power equipment and pipeline systems of ships, exploring the use of active and passive hybrid vibration isolation and adjustable dynamic vibration absorption technologies. It also proposes an adaptive feed-forward control strategy and studies a distributed feed-forward control hardware system. In addition, the book presents a three-way dynamic vibration absorption theory used to design a pipeline-system adjustable dynamic vibration absorber, which offers a number of advantages, such as compact structure, easy assembly and disassembly, low power consumption, excellent vibration control effect and wide frequency band adjustable ability, etc. This book is a valuable resource for researchers and engineers in the fields of noise and vibration control, active control systems, active vibration isolation and adaptive dynamic vibration absorption.
Download or read book Precision Controlled Actuation and Vibration Isolation Utilizing Magnetorheological MR Fluid Technology written by and published by . This book was released on 2001 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: PRECISION CONTROLLED VIBRATIONAL ISOLATION UTILIZING MAGNETORHEOLOGICAL FLUID TECHNOLOGY FOR POTENTIAL SPACE APPLICATIONS, SUCH AS SURVEIILLANCE AND DIRECTED ENERY, IS ADDRESSED.
Download or read book Magnetorheological Materials and Their Applications written by Seung-Bok Choi and published by Materials, Circuits and Device. This book was released on 2019-07 with total page 443 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces magnetorheological fluids and elastomers, and explores their material properties, related modelling techniques and applications in turn. The book offers insights into the relationships between the properties and characterisation of MR materials and their current and future applications.
Download or read book Novel Smart Magnetorheological Elastomer Vibration Controller written by Wei Wang and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advanced Elastomers written by Anna Boczkowska and published by BoD – Books on Demand. This book was released on 2012-09-12 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an extensive overview of current trends in the area of elastomers and their composites from the chapters contributed by internationally recognized specialists. The book deals with novel synthesis, modelling and experimental methods in elastomers. Contents include: new approach to crosslinking, liquid crystal elastomers, nanocomposites, smart elastomers, elastomers in microelectronics and microfluidics, elastomers in cement concrete and mortar, experimental testing and modelling. Each section demonstrates how enhancements in materials, processes and characterization techniques can improve performance in the field of engineering. The book provides a unique opportunity to discover the latest research on elastomer advances from laboratories around the world. This book addresses to industrial and academic researchers in the fields of physical, chemical, biological sciences and engineering.
Download or read book Vibration Isolation written by John C. Snowdon and published by . This book was released on 1979 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Combined Shock and Vibration Isolation Through the Self powered Semi active Control of a Magnetorheological Damper in Parallel with an Air Spring written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Combining shock and vibration isolation into a single isolation system package is explored through the use of an air spring in parallel with a controlled magnetorheological fluid damper. The benefits of combining shock and vibration isolation into a single package is discussed. Modeling and control issues are investigated and test and simulation results are discussed. It is shown that this hybrid isolation system provides significantly increased performance over current state-of-the-art passive systems. Also explored is the feasibility of scavenging and storing ambient shipboard vibration energy for use in powering the isolation system. To date the literature has not adequately explored the direct design of a combined shock and vibration isolation system. As shock and vibration isolation are typically conflicting goals, the traditional approach has been to design separate shock and vibration isolation systems and operate them in parallel. This approach invariably leads to compromises in terms of the performance of both systems. Additionally, while considerable research has been performed on magnetorheological fluids and devices based on these fluids, there has been little research performed on the use of these fluids in devices that are subjected to high velocities such as the velocity seen by a ship exposed to underwater near-miss explosive events. Also missing from the literature is any research involving the scavenging and storage of ambient shipboard vibration energy. While the focus of this work is on the use of this scavenged energy to power the subject isolation system, many other uses for this energy can be envisioned. Experimental and analytical results from this research clearly show the advantages of this hybrid isolation system. Drop tests show that inputs as great as 167 g's were reduced to 3.42 g's above mount at 1.11 inches of deflection using a Velocity Feedback controller suggested by the author. When contrasted with typical test results with similar inputs, the subject isolation system achieved reductions in above mount accelerations of 300% and reductions in mount deflections of 200% over current state-of-the-art passive shipboard isolation systems.
Download or read book Advances in Elastomers I written by P. M. Visakh and published by Springer Science & Business Media. This book was released on 2013-03-29 with total page 497 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first volume of a two-volume work which summarizes in an edited format and in a fairly comprehensive manner many of the recent technical research accomplishments in the area of Elastomers. “Advances in Elastomers” discusses the various attempts reported on solving these problems from the point of view of the chemistry and the structure of elastomers, highlighting the drawbacks and advantages of each method. It summarize the importance of elastomers and their multiphase systems in human life and industry, and covers all the topics related to recent advances in elastomers, their blends, IPNs, composites and nanocomposites. This first volume focuses on advances on the blends and interpenetrating networks (IPNs) of elastomers.
Download or read book Design and Dynamic Practice of a Novel Fluid Vibration Isolator for Packaging Protection of Electronic Equipment written by Yang Ping and published by . This book was released on 2007 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this paper is to study a novel fluid-coupling vibration isolator to improve the dynamics in a harsh vibration-impact environment for packaging reinforcement systems of electronic equipment. The fluid-coupling isolator is designed through coupling the air, oil, rubber, and spring. The dynamic characteristics of the actual fluid-coupling isolator are developed. The test results of the prototype in dynamic tests show complex nonlinear dynamic characteristics. Based on this, a nonlinear dynamic model for the fluid-coupling isolator is presented. Comparisons with experimental data confirm the validity of the model. It builds a basis for future work in engineering design and evaluation of packaging protection system for electronic equipment.
