Magnetorheological Brakes Research Articles

Design of a tooth-shaped magnetorheological brake with multiple coils

This research presents an optimized design for a tooth-shaped magnetorheological brake (MRB) with multiple coils. The MRB configuration consists of a disk immersed in magnetorheological fluid (MRF), where four coils act as electromagnets when an electric current is applied. The energized coils induce the alignment of suspended particles in the MRF, forming a chain-like structure that increases the fluid's viscosity. This rapid, strong, and controllable phenomenon enables the MRB to find applications in haptic systems, tension control, and industrial braking systems. To analyze the electromagnetic behavior of the brake, Finite Element Method (FEM) simulations are conducted using ANSYS APDL, and the optimization process is performed utilizing ANSYS Workbench software. The software provides optimized geometries for the brake, resulting in significant improvements in desired performance aspects compared to prior designs, etc.

Effect of temperature on braking performance of the comb-type disc magnetorheological brake

To investigate the effect of internal temperature variation of the comb-type disc magnetorheological brake on braking performance, firstly we simulate the temperature field analysis of magnetorheological brake by using the finite element method, and verify the reasonableness of the simulation using experiments. Secondly, the temperature variation of comb magnetorheological brakes during intermittent 5 min braking and continuous braking and the effect of temperature on the braking torque were investigated experimentally. The experimental results show that as the number of braking increases, the maximum temperature inside the brake increases until saturation, while the braking torque decreases. This research helps to enhance the realization of braking stability over the effective operating temperature range.

Investigating the Impact of Circular Sector Pole Head Structure on the Performance of a Multipole Magnetorheological Brake

The magnetorheological brake (MRB) epitomized a revolutionary modification in the braking systems because of its extremely efficient and well-controlled performance. To increase the safety and controllability of automotive braking system, researchers have developed a different MRB structures. Although much research on magnetorheological brakes has shown positive results in terms of brake torque, braking time, thermal efficiency, etc., the ability to increase braking force by expanding the disc surface, through which the magnetic field operates in a compact structure, is restricted. To address this issue, a new multipole MRB configuration with a unique pole head design that maintains compactness. Initially, the conceptual design was achieved by leveraging the combined impact of the twin disc-type structure and multipole concept. The model was used in a dynamic simulation to show how the braking torque of a magnetorheological braking system varies with coil current. The effects of circular sector pole head shape on braking performance were investigated using COMSOL Multiphysics software (version 5.5). A three-dimensional electromagnetic model of the proposed MRB was developed to examine the magnetic flux intensity and the impact of magnetic field dispersion on the proposed pole head structure of a magnetorheological brake. Based on simulation results, the circular sector pole head configuration is capable of increasing the active chaining regions for the MR fluid on the rotor surface, allowing for a more effective use of magnetic flux throughout the whole surface of a rotating brake disc, thereby increasing the magnetic field usage rate. The acquired simulation results show an increase in braking torque while keeping a compact and practical design structure.

Research on braking torque model of magneto-rheological brake based on temperature effect

Magneto-rheological Brakes (MRBs) have attracted much attention because of their fast, controllable and adjustable braking performance. During the braking process, a lot of heat was generated by the excitation oil and the friction between magneto-rheological fluid and mechanical parts. The objective of this manuscript is to investigate the effect of temperature on the braking performance of MRB. The thermal distribution of MRB under different excitation current was analyzed through numerical simulation; The braking torque model based on temperature effect was established from microscopic point of view; The braking performance of MRB under different working conditions were tested through MR braking torque test platform, and the results not only revealed the influence of temperature, rotational speed and excitation current on the braking torque, but also verified the rationality and accuracy of the braking torque model. The research results fill the gap in the theoretical model and have important significance for the research on the braking performance of MRBs.

Electromagnetic Interaction Model between an Electric Motor and a Magnetorheological Brake

This article focuses on modelling and validating a groundbreaking magnetorheological braking system. Addressing shortcomings in traditional automotive friction brake systems, including response delays, wear, and added mass from auxiliary components, the study employs a novel brake design combining mechanical and electrical elements for enhanced efficiency. Utilizing magnetorheological (MR) technology within a motor–brake system, the investigation explores the influence of external magnetic flux from the nearby motor on MR fluid movement, particularly under high-flux conditions. The evaluation of a high-magnetic-field mitigator is guided by simulated findings with the objective of resolving potential issues. An alternative method of resolving an interaction between an electric motor and a magnetorheological brake is presented. In addition, to test four configurations, multiple absorber materials are reviewed.

Tribological and braking performance study of additive-based MR fluids in shear and hybrid mode using MR drum brake

The braking performance of magnetorheological (MR) brake can be improved by utilizing hybrid mode of operation of MR fluid in brake and by enhancing the rheological properties of MR fluid. This work presents an MR drum brake, which can operate in shear mode as well as in shear plus compression mode, i.e., hybrid mode. The use of compression mode increases the interactions of iron particles with the contacting surface of the rotor and stator, which affects the gap of the MR zone, which is one of the performance parameters for MR brakes. Hence, the presented work attempted to prepare an MR fluid that offers not only good tribological properties as well as best braking performance with MR drum brake. So, MR fluids have been prepared using the same percentages of different additives such as graphite flakes, MWCNTs, and zinc oxide. The rheological, tribological, and braking performance of these prepared MR fluids have been studied using a rheometer, tribometer, and brake inertia dynamometer, respectively. The study found that zinc oxide-based MR fluid is the most suitable MR fluid for the presented MR drum brake in terms of braking performance and tribological aspects.

Study of Effect of Graphite Based Magnetorheological Fluids on Braking Performance and Rotor Surface of Magnetorheological Disk Brake Using Full-Scale Brake Inertia Dynamometer

The performance of magnetorheological (MR) brakes depends on the rheological and tribological properties of MR fluid. An additive-free MR fluid does not offer better braking performance, which limits the commercial application of MR brake. In view of these issues, MR fluids were prepared in this present work employing graphite flakes as an additive. The required rheological properties of these MR fluids were measured on the magneto rheometer, and their braking performances were measured as per braking standard IS13453 using a fabricated MR disk brake on a 2/3-wheeler brake inertia dynamometer. Due to the interaction of MR fluid with the rotor and housing surface, the MR gap (i.e., another performance parameter) varies. Therefore, the effect of the interaction of prepared MR fluids on the rotor surface properties of the MR disk brake was also investigated. The constituents of MR fluids generate roughness on the rotor and housing surface. As a result, a mathematical model for surface roughness was presented and verified with experimental results. Based on the study, it is found that 0.5% (w/w) of graphite flake is better than additive-free MR fluid.

Magnetorheological fluids: A comprehensive review

The magnetorheological (MR) fluids contain magnetic micro-sized iron particles, non-magnetic-based fluid, and some additives in order to mitigate sedimentation and agglomeration. The various carrier fluids used in the preparation of MR fluids are mineral oil, silicon oil, castor oil, soybean oil, kerosene, synthetic oils, honge oil, organic oil, water-based oils, etc. However, for obtaining better vibration control, silicone oil is the most preferred one due to its higher viscosity index, lower friction characteristics, higher flash point, and higher shear strength. The MR fluids have various application areas such as dampers, prosthetic knees, valves, brakes, clutches, finishing processes etc. The dampers containing MR fluids are used in automobile cushioning for enhancing passenger comfort and MR suspensions significantly improve steering stability in vehicles. In case of MR brakes, the braking torque on the rotating disks is controlled using the generated shear stress. The carbonyl iron (CI) particles exhibit better rheological characteristics as compared to electrolytic iron (EI) particles. The use of MR fluids produces stable and natural limb movement in orthoses, lower limb prostheses, and exoskeletons. The MR fluids also prove to be very significant in polishing applications. There are various issues with preparation methods and difficulties in the storage of MR fluids. The problems encountered in the synthesis of MR fluids include sedimentation, agglomeration, in-use thickening, corrosion, erosion, etc. The impact of particle proportion, particle shapes, and size has been influential in evaluating MR characteristics. The viscosity and shear stress of MR fluid have been mitigated at higher values of temperature and even CI particles get oxidized at higher temperatures. The CI particles as compared to EI particles are the majority favourable particles used for dispersing state within the MR fluids due to their higher value of saturation magnetization, more availability, and lesser cost. The small-sized particles led to lower wettability, whereas larger-sized particles accounted for an increased sedimentation rate. The currently available MR fluids cost is still on the higher side and the preparation of economical MR fluid is still a big challenge for the researchers. The MR fluids storage is also a big concern. The future scope of MR fluid may be in heavy industries such as nuclear, shipbuilding, oil and gas, space and aviation, etc. to achieve the desired damping response.

A study the effect of key parameters on the magneto-rheological brake torque based on the simulation method

This paper presents the design and simulation of a magnetorheological brake (MRB) model that supports a van truck downhill without interfering with the traditional brake system available on this vehicle. A research brake model using rheological magnetic fluid, an intelligent material. The operation of MR fluid-based brakes has inherent advantages such as continuously changing dynamic range and fast response. The research presents the process of calculating and simulating the braking torque generated by this brake model. This research helps to open up a new direction for the traditional brake system in cars. Consequently, the safety of the movement of cars, in particular, and vehicles in general during downhill is compromised. Based on the simulation model, the effect of key parameters (operation conditions, MRB tooth tilt angle, MRB rotor thickness, and number of MRB teeth) on the brake torque was completely presented.

Antilock braking performance evaluation of an automotive magnetorheological braking system

The aim of this work is to propose a novel magneto-rheological (MR) braking system (MRBS) using a magneto-rheological brake (MRB) and evaluate its anti-lock braking performance by theoretical analysis, numerical simulation and experimental verification. Firstly, the linear control mathematical model of the MRB is derived by the operation principle of the MR effect and the structure size of the MRB. Secondly, four different anti-lock braking controllers are designed for the MRBS to analyse the control performance under various road conditions. Subsequently, a flywheel type 1/4 vehicle antilock braking system test bench is established for investigates the antilock braking performance of the MRBS. The simulation results demonstrate that the road recognition based fuzzy proportional integral derivative (RRBF-PID) controller can maximize the utilization of the road adhesion coefficient. Furthermore, the RRBF-PID controller can shorten the braking time and distance, as well as maintain the stability of the braking direction during the braking process. In this work, the MRBS exhibits a satisfactory antilock braking performance under different road conditions and the research results could provide a reliable theoretical and experimental basis for the MRBS.

Optimal Design and Control Performance Evaluation of a Magnetorheological Fluid Brake Featuring a T-Shape Grooved Disc

Magnetorheological fluid brakes are a promising technology for developing high-performance drive-by-wire braking systems due to their controllability and adaptability. This research aims to design an optimal magnetorheological fluid brake for motorcycles and their performance. The proposed model utilizes mathematical modeling and finite element analysis using commercial software. Furthermore, the optimization of this MR brake is determined through multi-objective optimization with a genetic algorithm that maximizes braking torque while simultaneously minimizing weight and the cruising temperature. The novelty lies in the geometric shape of the disc, bobbin, and MR fluid channels, which results in a light MR brake weighing 6.1 kg, an operating temperature of 89.5 °C, and a power consumption of 51 W with an output braking torque of 303.9 Nm. Additionally, the control performance is evaluated using an extended Kalman filter controller. This controller effectively regulates braking torque, speed, and slip rate of both the rear and front wheels based on road characteristics and motorcycle dynamics. This study’s findings show that the front wheel necessitates higher braking torque compared to the rear wheel. Moreover, the slip rate is higher on the rear wheel than on the front wheel, but the front wheel stops earlier than the rear wheel.

Effect of Pole Head Profile on Torque Performance of a Disc-Type Multipole Magnetorheological Brake

A magnetorheological brake (MRB) works on the shearing effect of MR fluid in the magnetic field to develop resistance between the stator and the rotor, which are relative moving surfaces. Researchers achieved high torque volume ratios in magnetorheological fluid braking systems by adding multiple layers and using multipole approaches. Even though several designs already exist, there is a need for innovative ideas and advanced structures of MRBs for practical engineering applications. The number of magnetic poles, pole geometry and placement have a significant effect on the performance of multipole MR brakes. This research focused on the effect of the pole head geometry in a multipole dual disc compact MR brake to understand the relationship between the geometry and its magnetic flux flow. The magnetic field generated by the electromagnetic coil’s orthogonal travel through pole heads, rotor and MR fluid layers results in friction to fulfill the action of braking that achieves maximum brake torque. This flow depends on the magnetic pole head area and corresponding core dimensions. This study considered polygon, square, hexagon, trapezoid and ellipse pole head profiles in place of the conventional circular pole and the best possible core dimensions were used for each geometry. To study the brake’s performance, COMSOL Multiphysics software (version 5.5) commonly used for 3D electromagnetic modeling was used to simulate and examine the magnetic flux intensity for various pole head configurations. Results indicate an improvement compared to previous works, considering the same dimensional limitations and the flux leakage between the adjacent poles being much less. The hexagonal and elliptical pole heads had better magnetic field area, magnetic intensity distribution and higher magnetic flux lines piercing through the MR fluid perpendicularly than the circular and square pole heads. An increment of 3.88% for braking torque performance was obtained, and the braking torque was significantly enhanced.

Path tracking of Mr Fluid braking System based on PID control

With the rise of intelligent vehicle and driverless technology and the continuous improvement of vehicle speed, people have higher and higher requirements for vehicle safety performance. Mr Brake can be integrated with vehicle electronic control system to improve the corresponding speed of the braking system to a large extent and shorten the braking distance of the vehicle. This paper introduces the design theory and analysis of Mr Fluid. The working principle is introduced, and the torque required by the front and rear wheels of the vehicle braking process is deduced by the vehicle dynamics model. The Mr Fluid braking model based on PID control is built by using Matlab-simulink software. By tracking the straight line without fluctuation, the straight line with fluctuation and the right Angle path, the simulation results show that By adding PID control model to the magnetorheological braking control, it can effectively reduce the overshoot in the fluctuating route during the braking process, and the corresponding speed is faster and the path tracking effect is better, which provides an innovative thinking method for the development of vehicle brake and the development of driverless technology.

Design and Simulation of Magnetorheological Brake Supporting Downhill Van Truck

Depressing the brake when the vehicle is moving downhill for a long time will have a bad effect on the car's brake system. Typically, the phenomenon of friction, wear, and temperature rise occurs at the brake pads. These can be the causes of brake failure. This paper presents the idea of designing and simulating magneto-rheological brake (MRB) model to assist van trucks downhill without interfering with the traditional braking system. Research on brake models using: Magneto-rheological fluid (MRF), a smart material that is gradually being applied in many fields of science and technology. The operation of this type of brake is based on the inherent advantages of MR fluids such as continuously changing dynamic range and fast response, actively changing the viscosity of the fluid when changing the magnetic field applied to the coil. In order to improve safety and initiative in the braking process of the car. The study presents the process of calculating and simulating the braking torque generated from this brake model. Thereby helping to open a new direction for the traditional brake system in cars as well as contributing to the development of the automobile industry in general.

Optimal design and stability control of an automotive magnetorheological brake considering the temperature effect

Magnetorheological brake (MRB) provide a potential alternative to traditional mechanical friction brakes in automobile applications owing to their technical advantages in terms of being compact yet powerful, having superior control performance, and wire-control features. However, the temperature effect has been an important issue that should be considered in the design and precise control of MRB. This paper presents the multi-objective optimal design and stability control of an automotive MRB considering the temperature effect. First, a description of the configuration design, magnetostatic field simulation, and mathematical modeling of the automotive MRB is presented in detail. Subsequently, design optimization of the MRB is carried out. The design of experiment method was adopted to screen out the major design variables, and the optimal solution was obtained using a multi-objective genetic algorithm (GA) non-dominated sorting genetic algorithm (NSGA-II). Thereafter, the torque output and response performance, as well as the temperature characteristics of the optimal MRB prototype are experimentally evaluated. The results indicate that the optimal design of the MRB was reasonable and effective. Finally, a GA-based back propagation neural network proportion integration differentiation controller is proposed for the stability control of the MRB during automobile braking. Its performance was verified to be satisfactory through both simulations and experiments.

SIMULATION-BASED INVESTIGATION OF THE EFFECTS OF MAJOR PARAMETERS ON MAGNETORHEOLOGICAL BRAKE TORQUE

In this paper, a magnetorheological brake (MRB) model that supports a van truck going downhill without interfering with the conventional braking system installed on this vehicle is designed and simulated. The simulation model demonstrates the impact of key variables on brake torque, including operation conditions, MRB tooth tilt angle, MRB rotor thickness, and MRB tooth count. As a result, the simulation results show that the maximum brake torque value is about 136.41 Nm at the 75-degree inclination angle of the tooth disk. The MRB rotor thickness does not have many effects on the brake torque. The maximum brake torque (138.7 Nm) can be achieved at 10 cm rotor thickness. The brake torque increases following an increase in the number of MRB teeth. The brake torque increases by 6% when the number of teeth increases from 1 to 3. Keywords: Magnetorheological Fluid, Magnetorheological Brake, MRB Tooth Tilt Angle, MRB Rotor Thickness, Braking Torque DOI： https://doi.org/10.35741/issn.0258-2724.58.3.21

Two-link Manipulator Driven by a Pair of Antagonistic Rubber Artificial Muscle

Pneumatic rubber artificial muscles have been extensively researched as a driving device capable of soft movements that are compatible with humans, and are expected to be applied to human friendly robots. However, it is difficult in principle to achieve high-precision positioning and high-rigidity position retention due to low stiffness and delayed response as a result of air compressibility. Normally, a 2-link manipulator requires 4 (2 pairs) artificial muscles, but here, by attaching two MR brakes to each axis and switching the drive shaft, a manipulator that controls a 2-link manipulator with 2 (1 pair) artificial muscles, is proposed.

DEVELOPMENT OF A ROTARY SEALING COMPONENT FEATURING MR FLUID AND PERMANENT MAGNET

In this research work, a self-sealing component for rotary shaft of Magneto-rheological (MR) fluid based devices such as MR brakes and MR clutches is designed and tested by both simulation and experiment. The sealing component is composed of a permanent magnet and a magnetic core placed on a rotary shaft to replace a traditional lip-seal. After an overview of MR fluid and its applications as well as researches on sealing components based on MR fluid, a configuration of a self-sealing component for rotary shaft of a MR fluid based device is proposed. Afterwards, the design and modeling of the sealing component is then conducted based on Bingham plastic rheological model of the MR fluid and finite element analysis. Based on finite element analysis, optimal design of the sealing component is obtained. Prototypes of the sealing component are then manufactured and experimental works are then conducted. Base on experimental results, performance characteristics of the sealing component are investigated and compared with simulated results.

Development of Tiny Vane-Type Magnetorheological Brake Considering Quality Function Deployment.

Many studies focus on the torque-to-dimension ratio when designing magnetorheological brakes (MRB), especially for ankle foot orthosis (AFO) devices. Vane MRB is one type of MRB with a limited angle of motion that is naturally suitable to be applied to AFO. However, very few implement quality function deployment (QFD) when making MRB, whereas QFD is an essential factor in making product designs. In this study, a tiny vane-type MR brake (TVMRB) was successfully made using the QFD method. Torque characteristics are determined by analysis of magnetic flux density, theoretically, by 3D simulation, and by using Ansys Maxwell experimentally. For consideration, the analysis was carried out with fluid gap variations (0.5 mm, 0.75 mm, and 1 mm) and current variations (0.5-2 A with 0.5 A increments). As a result, ignoring the leakage of MR fluid (MRF), at a constant rotation of 10 rpm, the smallest torque of 6.14 Nm was obtained at the fluid gap variation of 1 mm and input current of 0.5 A, whereas the largest torque was 46.71 Nm at the fluid gap variation of 0.5 mm and input current of 2 A. Apart from torque, this article will also discuss other brake performances in the form of operational range and power consumption. Finally, the structure of the TVMRB design is compared with other designs presented in the House of Quality (HOQ).

Numerical simulation of an electromechanical brake concerning associated difficulties

The biggest challenge in developing any type of brake (or any other actuator) is overcoming its inherent disadvantages. Brakes that use materials whose rheological properties change under the influence of an external magnetic field are called magnetorheological brakes. In addition to the mechanical issues, magnetorheological brakes are troubled with cooling, sealing, settling, fluids' gap size, etc. Furthermore, there are issues with brake’s magnetic field density distribution and propagation. The poor distribution of the magnetic field density through the body of the magnetorheological brake is one of these inherent disadvantages. Magnetorheological’s brake magnetic circuit modeling forms the basis for further development. This paper is part of ongoing research into the feasibility of using magnetorheological brakes in automotive applications. Certain points of the numerical simulation process are addressed. The research uses part of the results from previous numerical simulations, carried out using commercial finite element method software - COMSOL Multiphysics, AC/DC module, and results from the previous experiments.