Magnetorheological Damper Research Articles

An adaptive backstepping sliding mode control strategy for the magnetorheological semi-active suspension

This paper proposes an adaptive backstepping sliding mode control strategy for addressing nonlinear issues in the semi-active suspension systems, such as uncertainties and external disturbances. Firstly, a hyperbolic tangent model is chosen for parameters identification of the magnetorheological (MR) damper, and a model for the semi-active suspension system is established. Secondly, a control strategy is designed by combining the backstepping and sliding mode control strategies, and adaptive methods are employed to mitigate external disturbances, enhance the robustness of the controller, and estimate system uncertainties. Finally, the stability and controllability of the closed-loop system are verified using Lyapunov theory. Under the road excitations of A-Class, B-Class, and speed bump, the dynamic characteristics of the passive control, backstepping sliding mode control, and adaptive backstepping sliding mode control strategies applied to the MR semi-active suspension are analyzed. The vertical acceleration of vehicle body, suspension dynamic deflection, and tire dynamic load are selected as evaluation indexes, the results indicate that this control strategy significantly improved the ride comfort and handling stability of the vehicle.

Vibration damping by enhancing of magneto-rheological damper performance using novel smart fluid

The objective of the present work is to improve the speed and vibration characteristics of tracked vehicles via a semi-active suspension system that uses a Magneto-Rheological (MR) damper. MR damper is designed, manufactured, and tested with different harmonic excitations. The MR damper reliability under high-frequency stresses is considered in the mechanical design phase as well as the configurations and dimensions of the damper. Two fluid samples DELTA and GAMA are prepared, which differ in carrier fluid dynamic viscosities to have different rheological properties and tested to determine the dynamic characteristics of the damper. The damper’s ability to isolate vibration is measured by MTS. The investigation performed not only clarifies MR fluid characteristics but also proves the fact that the fluid is non-Newtonian with good rheological properties. One of the two fluid samples called DELTA is found to have the required properties. The MR damper filled with this DELTA shows a significant increase in damping force according to the excitation current and is much higher than the conventional passive suspension damping force. The proposed damper can cope with the increase in both magnitude and frequency of the input, which represents the speed of the truck and roughness of the road. Upgrading the suspension system of the vehicle from a passive damper to a manufactured semi-active MR damper with MR fluid DELTA can increase the damping force that the passive damper produces by 207% in compression stroke and 136.2% in rebound stroke at the same testing conditions.

Multi-condition adaptive detail characterization model of magnetorheological dampers and experimental verification

The theoretical model for predicting the damping characteristics of magnetorheological dampers (MRDs) is significant for enhancing the design efficiency of the control algorithm. However, some existing theoretical models face limitations in characterizing MRD damping characteristics simultaneously in terms of nonlinear detail characterization and adaptability to variable working conditions. Therefore, this paper proposed the Composite Double-Boltzmann (CDB) model combining the Double-Boltzmann (DB) function widely used in the field of biology and chemistry for its strong nonlinear characterization capability. Utilizing this model to fit the sinusoidal vibration testing data of the MRD prototype under variable combination working conditions, obtaining quantitative relationships between the undetermined parameters in the CDB model and the excitation current, vibration frequency, and amplitude to enable the model to address both the nonlinear details characterization of MRDs and adaptability to variable working conditions. Subsequently, the validity of the quantitative relationships were verified by comparing the calculated parameter values using the quantitative relationships with the original accurate parameter values. In order to verify the validity of the CDB model, extensive unknown working condition vibration tests were conducted on the MRD prototype under variable excitation currents, vibration frequencies, amplitudes and random excitation working conditions, employing the CDB and Tanh models to predict the damping characteristics, to compare to demonstrate the CDB model’s capability of adapting to variable working conditions while accurately characterizing the nonlinear details of MRD damping characteristics.

A rotary self-sensing magnetorheological damper based on triboelectric nanogenerator

A rotary self-sensing magnetorheological (MR) damper(RSMRD) based on a triboelectric nanogenerator is proposed in this study, which can provide variable torque and state self-sensing without a power supply. Compared with traditional self-sensing devices, the sensing part of RSMRD has the advantages of small size, no external power supply, and good low-frequency response. The feasibility of the angular velocity self-sensing (AVS) function is verified through theoretical derivation and experimental verification. The experimental results demonstrate a linear relationship between the output voltage generated by the AVS component and the rotational speed of the rotating shaft. Additionally, the torque characteristics of the rotary self-sensing MR damper are tested, revealing a torque generation of approximately 9.26 N ⋅ m at a current of 1.6 A. Furthermore, a fuzzy control algorithm for vehicle braking is proposed, based on the model parameters of RSMRD. The simulink software is used to establish a dynamic model of 1/4 car braking, with an initial braking speed of 15 m s−1. The results indicate that the vehicle comes to a complete stop after 1.64 s, with a braking distance of 10.93 m. Throughout the braking process, the vehicle slip rate remains close to the optimal slip rate of 0.2.

Dynamic performance evaluation of a magnetorheological damper-based sting support in wind tunnel tests

The sting support faces an issue of being prone to resonance due to its low-damping characteristics, which will compromise the accuracy of test data in wind tunnel experiments. Magnetorheological damper (MRD)-based tail support (MRSS) features varying stiffness and damping abilities, enabling it to suppress the vibration with random, time-variation characteristics in a self-adaptive way, and it also exhibits excellent fail–safe properties. This work aims to validate its controllability and fail–safe property in a wind tunnel environment. First, the natural frequency, root mean square (RMS), and power spectral density (PSD) of the designed MRSS’ response for random excitation were theoretically analyzed. Then, wind tunnel experiments were conducted to test the response under different attack angles, wind speeds, and test currents. Subsequently, the controllability and fail–safe property were demonstrated by analyzing the aircraft model response. Also, the variable stiffness and damping properties of MRD behind the observed phenomena were revealed based on the theoretical analysis. Results demonstrate that as the input current increases and the MRD’s stiffness continues to increase, the damping initially increases and then decreases. Increasing wind speed leads to a decrease in the MRD’s stiffness. Additionally, approximately 50% reduction in RMS and a multi-modal response attenuation was achieved.

Interval Sensitivity Analysis and Optimization of Magneto-Rheological Damper with Energy Harvesting Characteristics

Interval Sensitivity Analysis and Optimization of Magneto-Rheological Damper with Energy Harvesting Characteristics

An omnidirectional low-frequency wave vibration energy harvester with complementary advantages of pendulum and gyroscope structures

To address the challenge of omnidirectional low-frequency wave vibration energy harvesting, this paper proposes a wave vibration energy harvester that combines a pendulum structure with a gyroscope structure. The Euler-Lagrange equation of the harvester kinematic model is established and solved to confirm its complementary advantages. The pendulum structure initiates the rotation of the magnetic levitation flywheel through the gears, and directs the flywheel precession to achieve a greater gyroscopic torque. The gyroscope structure generates gyroscopic torque, which helps the pendulum structure easily pass-through positions where the mass torque is small. The two structures work together to overcome the electromagnetic damping and generate electricity. This increases the power output and power density. An experimental platform for wave simulation is built to test the energy harvester. The results show that at a frequency of 1 Hz and an amplitude of ±20°, the average power output of the energy harvester is 67.51 mW when the load is 910 Ω, and the flywheel speed is 899.51 rpm. This is of great significance for the application of self-powered wireless sensors in smart ocean.

Robustness analysis for the vibration control performance of energy-harvesting tuned mass damper with uncertainties

Energy-harvesting vibration control strategy has been proposed and applied in different applications, including but not limited to automotive, mechanical, and civil engineering. However, when facing uncertainties from both internal and external environments, the robustness of its performance has rarely been evaluated. The energy-harvesting tuned mass damper (EHTMD) is a representative vibration control device integrated with the energy-harvesting function. This study investigates the robustness of an EHTMD installed on a structure with multi-uncertainties. First, the EHTMD modeling, the interval model, and the robustness evaluation framework are introduced. Uncertainties are considered for all parameters of an EHTMD, including the mechanical units, electromagnetic damper, and energy harvesting circuit. Subsequently, a series of dynamic simulations are performed on a damped benchmark single-degree-of-freedom frame with an EHTMD. The lower- and upper-bound structural vibration and generated power are estimated under free-vibration, harmonic-excitation, and random-excitation scenarios. The EHTMD performance robustness is evaluated through the interval response by incorporating the first-passage theory. The key factors in EHTMD that influence its robustness are identified. Results indicate promising robustness when using the energy-harvesting vibration control strategy to replace the conventional dampers, addressing one of the often-questioned issues of the energy-harvesting vibration control strategy.

Magnetohydrodynamics Flow of Hybrid Nanofluid Rotating in Annulus Through Two Coaxial Cylinders

A numerical investigation is conducted to examine the flow characteristics of the hybrid nanofluid rotating through an annulus formed within a coaxial cylinder. The study compares the heat performance of the hybrid nanofluid [composed of graphene oxide (GO), copper (Cu), and kerosene oil] with the base fluid (kerosene) and a nanofluid consisting of copper and kerosene oil. The inner wall of the coaxial cylinder remained stationary, while the outer wall underwent rotation. Additionally, a radial magnetic field was applied to examine its impact on flow and heat transfer characteristics. This study explores two scenarios: one where all walls are electrically insulating and another where the outer and inner walls are electrically conducting. The mathematical model, formulated as partial differential equations, was solved using the finite volume method. Graphical representations were used to analyze azimuthal velocity, temperature, Nusselt number, and skin friction under increasing magnetic intensity. The results indicated that a higher magnetic Hartmann number led to an increase in the distribution of temperature and azimuthal velocity in the middle of the annulus. Additionally, a higher magnetic field leads to an increase in the Nusselt number, which is more advantageous for the hybrid nanofluid than for Cu/kerosene oil. Electromagnetic damping is more evident in heat transfer when the inner/outer walls are electrically conducting than when all walls are insulated, as highlighted by the findings.

Hybrid damping control of magnetorheological semi-active suspension based on feedback linearization Kalman observer

Hybrid damping control of magnetorheological semi-active suspension based on feedback linearization Kalman observer

Methodology for Design of Magnetorheological Dampers to Protect Wires of Overhead Power Lines

Methodology for Design of Magnetorheological Dampers to Protect Wires of Overhead Power Lines

Adaptive Control for Suspension System of In-Wheel Motor Vehicle with Magnetorheological Damper

This study proposes two adaptive controllers and applies them to the vibration control of an in-wheel motor vehicle’s (electric vehicle) suspension system, in which a semi-active magnetorheological (MR) damper is installed as an actuator. As a suspension model, a nonlinear quarter car is used, providing greater practical feasibility than linear models. In the synthesis of the controller design, the values of the sprung mass, damping coefficient and suspension stiffness are treated as bounded uncertainties. To take into account the uncertainties, both direct and indirect adaptive sliding mode controllers are designed, in which the principal control parameters for the adaptation law are updated using the auto-tune method. To reflect the practical implementation of the proposed controller, only two accelerometers are used, and the rest of the state values are estimated using a Kalman observer. The designed controller is applied to a quarter car suspension model of an in-wheel motor vehicle featuring an MR damper, followed by a performance evaluation considering factors such as ride comfort and road holding. It is demonstrated in this comparative work that the proposed adaptive controllers show superior control performance to the conventional proportional–integral–derivative (PID) controller by reducing the vibration magnitude by 50% and 70% for the first and second modes, respectively. In addition, it is identified that the second mode (wheel mode) of the in-wheel motor vehicle is more sensitive than the first body mode depending on the mass ratio between the sprung and unsprung mass.

Design and experimental evaluation of a novel flow-mode magnetorheological damper without accumulator

Researchers in the field of vibration control have shown increasing interest in magneto-rheological dampers (MRDs) in recent years. Conventional flow-mode MRDs typically employ a gas chamber as an accumulator to accommodate volume changes and promote fluid communication. However, this approach introduces manufacturing complexities and raises production costs. To overcome these challenges, we propose a novel configuration for flow-mode MRDs that replaces the accumulator with a structural constraint. This modification leads to a more compact and cost-effective MRD solution suitable for engineering applications. This paper presents an introduction, followed by the configuration and design of the novel MRD for a case study involving a vehicle suspension system. To enhance output performance, we optimize the significant geometry of the damper using the finite element method (FEM), taking into account the damping force, off-state force, and inductive time constant of the damper. Based on the optimal simulation results, we provide a detailed design of the optimized flow-mode MRD without an accumulator for prototype fabrication. To assess the practical performance of the proposed MRD prototype, we conducted experiments on a test rig and engaged in comprehensive discussions based on the obtained results.

SIMULATION STUDY ON PARAMETRIC MODELLING OF MAGNETORHEOLOGICAL DAMPER SYSTEM

The Magnetorheological (MR) damper system serves as a semi-active suspension system designed to absorb road disturbances. This research aims to replicate the MR damper system through a parametric modeling approach, specifically employing the Simple Bouc-Wen Model, Spencer Model, and Hyperbolic-Tangent Model. The objective of this paper is to assess the effectiveness of these modeled MR damper systems with the utilization of a Fuzzy-PID controller. The simulation process is conducted within MATLAB Simulink, whereby a block diagram is devised based on equations related to the suspension system and the parametric models. The inputs for the system encompass sinusoidal and bump road profiles. The outcomes from the modeled MR damper systems reveal that the semi-active suspension system outperforms the passive suspension system. The primary simulation metrics under consideration include sprung displacement, sprung acceleration, and unsprung acceleration. Among the three MR damper models, the Hyperbolic-tangent model displays the most favorable performance, with a mean squared error of 51.44%, while the Bouc-Wen model exhibits the least favorable performance, registering a mean squared error of 25.96%. The integration of the Fuzzy-PID controller demonstrates an enhancement in the sprung suspension system, though the sprung acceleration remains relatively unchanged.

Study on nonlinear dynamics and semi-active control of a quasi-zero-stiffness magnetorheological damping floating slab track system

Study on nonlinear dynamics and semi-active control of a quasi-zero-stiffness magnetorheological damping floating slab track system

Adaptive Real Time Efficient Control Algorithm for Buildings Under Wind and Earthquake Forces

The study aims to tackle two key issues: the dependency of optimal controllers on available training data and their limited capability in managing multi-component structural responses. Real Time Fuzzy Logic Efficient Control system (RTFLEC) was developed to address these challenges. This system integrates a fuzzy logic inference system with a multi-verse optimization algorithm and utilizes real time training for real-time optimal controller derivation. It incorporates decentralized systems and optimal controller memory concepts and employs a magnetorheological damper (MR) for adjustable vibration control. Two case studies were conducted to evaluate the RTFLEC system's effectiveness. The first study focused on a three-story shear building under seismic loads, while the second analyzed a 76-story building facing multi-directional wind loads. The results showed that RTFLEC system reduced structural drifts by 28.33% and 51.5% during near-field and far-field earthquakes, respectively. It also decreased structural acceleration by 27.66% and 53% during near-field and far-field earthquakes, respectively. For wind-induced structures, it reduced story displacement by 37.5%, 14.5%, and 12% against across-wind, along-wind, and rotational forces, respectively. RTFLEC system demonstrated robust performance against uncertainties in external excitations, providing exceptional structural responses. Its key advantage lies in real-time adaptability, requiring minimal training data and computational processing. These findings highlight its significant potential in enhancing the performance of adaptive vibration control systems under unpredictable real-world loads.

NSGA-II-TLQR Control of Semi-active Suspension System with Magnetorheological Damper Considering Response Time Delay

NSGA-II-TLQR Control of Semi-active Suspension System with Magnetorheological Damper Considering Response Time Delay

Experimental study on seismic performance of CFRP bar reinforced concrete columns with magnetorheological damper

Concrete column with Carbon Fiber Reinforced Polymer (CFRP) bars as longitudinal reinforcement have good self-centering performance, but its energy dissipation property is relatively weak. This article proposed a method of adjust the energy dissipation capacity of the column without affecting its self-centering performance by installing magnetorheological (MR) damper outside the column. To verify the feasibility of this method, pseudo-static tests were conducted on a MR damper, one ordinary reinforced concrete column (RCC), and two CFRP bar reinforced concrete columns with MR damper (CFRP80 and CFRP150), and the currents of the MR damper were 80 mA and 150 mA. The experimental results showed that installing MR damper can effectively improve the carrying capacity, energy dissipation property and stiffness of CFRP bar reinforced concrete columns, and the greater the energizing current of the MR damper, the more obvious these effects. Compared with RCC, CFRP bar reinforced concrete columns have better self-centering performance and ultimate deformation. The residual drifts of RCC, CFRP80 and CFRP150 at the 4 % drift level were 2.50 %, 0.62 % and 0.58 %, respectively. The ultimate drifts of RCC, CFRP80 and CFRP150 were 2.79 %, 4.26 % and 4.34 %, respectively. In addition, the use method of the MR damper can ensure that it does not affect the self-centering performance of CFRP bar reinforced concrete columns.

Nonlinear passive magnetorheological damping characteristics of the scissor-like isolation platform

Nonlinear passive magnetorheological damping characteristics of the scissor-like isolation platform

Development of novel magnetorheological dampers with low-speed sensitivity for flying car suspensions

As urban traffic environments continue to grow in complexity, there is an urgent need for a versatile mode of transportation that seamlessly transitions between terrestrial and aerial mobility. In conventional magnetorheological damper (CMRD), the magnetorheological fluid flowing through the narrow annular gap between the piston and cylinder in CMRD results in a damping force directly proportional to velocity. As velocity increases, the damping force rises sharply, posing a significant risk to the vehicle’s mechanical structure and passenger safety. This velocity sensitivity restricts their applications primarily to standard commercial vehicle suspension systems. They face significant challenges when it comes to high-speed impact scenarios. To overcome this limitation, enhance the shock-absorbing capacity of flying cars, ensure passenger safety, and improve passenger comfort during the landing phase, this study introduces a novel magnetorheological damper (NMRD) with unique internal channel structure embedded in a circular permanent magnet. In road travel mode, NMRD maintains a wide dynamic range. During high-speed impact landing, when the impact force exceeds the threshold, the pressure relief channel opens, effectively reducing the peak impact force. This feature greatly expands the application range of magnetorheological dampers. The researches included simulations of the electromagnetic induction phenomenon within the piston, The pressure relief damping force inside the NMRD valve was accurately measured by using material testing system, the peak force and peak acceleration experienced by the two dampers during impact were tested using a dedicated drop hammer apparatus. These tests demonstrate that the NMRD exhibits superior impact resistance performance compared to CMRD. This highlights the promising potential for the NMRD’s application within the suspension systems of flying cars.