Magnetorheological Materials and their Applications

Description

The rheological properties of magnetorheological (MR) materials, such as their viscosity and dynamic modulus, can be tuned or controlled by changing the intensity of the magnetic field using appropriate control schemes. Thanks to their robustness, performance and smart properties, numerous studies have been undertaken on the development of new MR materials, and microscopic and macroscopic modelling approaches. Novel applications include engine mounts and clutch systems in the automotive industry, shock absorbing safety devices for cockpit seats in aerospace, and shock absorption from movement in semi-active human prosthetic legs. 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, making it useful reading for researchers, engineers and graduate students who work in the field of smart materials and structures. Cover Contents Preface 1 Redispersibility and its relevance in the formulation of magnetorheological fluids 1.1 Introduction 1.1.1 Methodology of the redispersibility test 1.2 Results and discussion 1.2.1 Effect of sedimentation time 1.2.2 Effect of additives in MRF formulation 1.2.3 Effect of centrifuging the MRF 1.2.4 Long-time settling (1-year) redispersibility 1.2.5 Redispersibility of MRF with 48 vol.% 1.3 Conclusions Acknowledgments References 2 DEM and FEM simulations in magnetorheology: aggregation kinetics and yield stress 2.1 Background 2.1.1 Discrete element method 2.1.2 Finite element method 2.1.3 More complex approaches 2.2 Methodology: numerical methods 2.2.1 Discrete element method 2.2.2 Finite element method 2.3 Results and discussion 2.3.1 Discrete element method 2.3.2 Finite element method 2.4 Conclusions Acknowledgments References 3 A new novel of composite adaptive optimal control for MR damper system subjected to mixed disturbances 3.1 Introduction 3.2 New novel of optimal control for nonlinear system 3.2.1 Proposed control law 3.2.2 Simulation of the proposed optimal control and discussion 3.3 Design of a new composite controller 3.3.1 Fuzzy model 3.3.2 Adaptive optimal control 3.4 Application to vibration control 3.4.1 Vehicle seat suspension system 3.4.2 Simulation results and discussions 3.5 Conclusion Acknowledgment Appendix A References 4 Developments in modeling of magnetorheological actuators 4.1 Introduction 4.2 Modeling 4.2.1 Electromagnetic domain 4.2.1.1 Steady-state lumped parameter modeling 4.2.1.2 Magnetostatic field modeling 4.2.1.3 Transient lumped parameter modeling 4.2.1.4 Transient magnetic field modeling 4.2.2 Flow domain 4.2.2.1 Steady-state flow modeling: lumped parameter approach 4.2.2.2 Steady-state CFDs 4.2.2.3 Unsteady fluid dynamics 4.3 Summary References 5 Use of magnetorheological shock absorber for impact loading mitigation with individually controllable coils 5.1 Introduction 5.2 Gun-recoil system 5.3 Design of multi-coil MR absorber 5.4 Time response of MR buffer system under impact loading 5.4.1 Impact test platform system 5.4.2 Current controller 5.4.3 Time delay compensation 5.4.3.1 Response analysis of electromagnetic drive circuit 5.4.3.2 Response analysis of MR impact system 5.4.3.3 Time delay compensation methods 5.4.3.4 DSP PID controller 5.5 Dynamic characteristics of MR buffer system 5.5.1 Conventional unified control mode 5.5.2 Separate control mode 5.5.3 Timing control mode 5.6 MR shock buffer device control strategy and experimental verification 5.6.1 Methods of MR damper control 5.6.2 MR shock buffer control system 5.6.3 Fuzzy logic control strategy 5.6.3.1 One-dimensional fuzzy control strategy 5.6.3.2 Two-dimensional delay fuzzy control strategy 5.6.4 Fuzzy control experiment 5.6.5 Experimental results and analysis of fuzzy control 5.7 Summary Acknowledgments References 6 Influence of magnetorheological stabilizer bar on vehicle roll stability 6.1 Introduction 6.2 MR semi-active stabilizer bar system 6.2.1 Vehicle roll dynamic model 6.2.2 MR stabilizer bar 6.2.2.1 Mathematical model 6.2.2.2 Force analysis of the MR stabilizer bar 6.2.3 The MR damper 6.2.3.1 MR fluids properties 6.2.3.2 Structural principle 6.2.3.3 Controllable torque 6.2.3.4 Electromagnetic simulation 6.2.3.5 Output characteristics 6.2.4 Control strategy for MR stabilizer bar 6.3 ADAMS/Car modeling and simulation 6.3.1 Comparison between ADAMS/Car model and mathematical model 6.3.2 Full-vehicle simulation 6.3.2.1 Fish hook maneuver 6.3.2.2 Single lane change maneuver 6.3.2.3 Pylon course maneuver 6.4 Conclusion References 7 Hybrid active and semi-active seat suspension 7.1 Hybrid active and semi-active seat suspension design and prototype 7.1.1 Motivation 7.1.2 Prototype 7.2 The seat suspension prototype test and model identification 7.2.1 Testing method 7.2.2 Test results 7.2.3 Model identification 7.3 Control algorithm 7.3.1 Hybrid seat suspension model 7.3.2 Controller design 7.4 Evaluation 7.4.1 Numerical simulation 7.4.2 Experimental setup 7.4.3 Experimental results 7.5 Conclusion References 8 Development of magnetorheological brake with magnetic coils placed on side housings 8.1 Introduction 8.2 Configuration of the side-coil MR brake 8.3 Modeling of the side-coil MR brake 8.4 Optimization of the side-coil MR brake with rectangular housing profile 8.5 Optimization of the side-coil MR brake with polygonal housing profile 8.6 Summary References 9 Enhanced magnetic-sensing characteristics for application of magnetorheological elastomer 9.1 Overview of magnetorheological elastomer 9.2 Material preparation of magnetorheological elastomer 9.2.1 Matrix 9.2.2 Magnetic particles 9.2.3 Additives 9.3 Test characterization of magnetorheological elastomers 9.3.1 Mechanism of magnetorheological elastomers 9.3.2 Application research of magnetorheological elastomer 9.4 Conclusions and prospect References 10 Multi-scale modeling on tensile modulus of magnetorheological elastomers 10.1 Tensile modulus in the absence of magnetic fields 10.1.1 Three parameters of RVE model 10.1.2 Theoretical solutions 10.1.3 FEM solutions 10.1.4 Results 10.2 Tensile modulus under applied magnetic fields 10.2.1 Magnetic-induced stress 10.2.2 The x, y direction tensile modulus under magnetic field 10.2.3 The z direction tensile modulus under magnetic fields 10.3 Anisotropy of the structured MRE 10.3.1 Tensile modulus in different direction 10.3.2 Tensile modulus in the different anisotropy microstructure 10.4 Conclusions References 11 Experimental study and mathematical model on different magnetorheological elastomers 11.1 MR elastomers fabrication 11.1.1 Selection of materials 11.1.2 Procedure of MRE specimens' fabrication 11.2 Performance tests of MREs 11.2.1 Test setup and procedure 11.2.2 Results and analysis 11.2.2.1 Physical property test 11.2.2.2 Quasi-static property test 11.2.2.3 Dynamic mechanical property test 11.3 Numerical simulations 11.3.1 The microphysical model based on chi-squared distribution 11.3.2 Magnetoviscoelasticity parametric model 11.3.3 Parameter identification 11.3.4 Numerical simulation results 11.4 Conclusion Acknowledgments References 12 Promising application of magnetorheological elastomer 12.1 Semi-active system 12.1.1 Generic tunable vibration absorber 12.1.2 Automotive application 12.1.3 Medical application 12.1.4 Robotic application 12.1.5 Machining application 12.2 Active system 12.2.1 Releasable attachment 12.2.2 Artificial muscle 12.2.3 Microfluidic and peristaltic pumping 12.2.4 Valve system 12.3 Sensory system 12.3.1 Impedance and magnetoresistance 12.3.2 Magneto-induced capacitor 12.3.3 Displacement sensor 12.3.4 Tire pressure sensor 12.3.5 Magnetic field sensor 12.3.6 Tactile sensor References 13 Development of a hybrid nonlinear vibration absorber working with MR elastomers 13.1 Structure, working principle, and analyses of the MRE absorber 13.1.1 Structure 13.1.2 Working principle 13.1.3 Analysis of the MRE absorber 13.2 Experiment test of the hybrid MRE absorber 13.2.1 Experiment setup 13.2.2 Testing result 13.2.2.1 Nonlinearity verification 13.2.2.2 Adaptability verification 13.3 Vibration reduction evaluation 13.3.1 Performance of the MRE absorber under different amplitudes 13.3.2 The performance comparison between passive absorber and controlled absorber 13.4 Conclusion References 14 Development of smart base isolation system for civil structures utilising magnetorheological elastomer 14.1 Introduction 14.2 Smart base isolation concept 14.3 Adaptive base isolator 14.3.1 Structure 14.3.2 Finite element analysis 14.3.3 Characterisation testing 14.4 Nonlinear hysteresis modelling 14.4.1 Parametric models 14.4.2 Non-parametric model 14.5 Control algorithms 14.5.1 LQR control with GRNN inverse model 14.5.2 GA optimised fuzzy-logic control 14.6 Experimental setup 14.6.1 Three-storey building 14.6.2 Isolation system assembly 14.6.3 Data acquisition and control system 14.6.4 Earthquake excitation 14.7 Results and discussions 14.7.1 Time history 14.7.2 Peek floor acceleration 14.7.3 Control force and applied current Acknowledgements References 15 The designation and mechanical properties of magnetorheological plastomer 15.1 Introduction 15.2 Fabrication methods of MRPs 15.2.1 Hydrogel-like MRP 15.2.2 Polyurethane MRP 15.2.3 Shear-thickening MRP 15.2.4 Thermosensitive MRP 15.3 Mechanical properties 15.3.1 MR effect of MRP 15.3.2 Dynamic mechanical properties of MRP 15.3.3 Magnetic–electric coupling properties of MRP 15.4 Mechanism 15.5 Application 15.6 Conclusion References Index