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A new cutting tool is always well-defined and sharp at the onset of the metal cutting process and gradually losses these properties as the machining process advances. Similarly, at the beginning of the machining process, amplitude of tool vibrations is considerably low and it increases gradually and peaks at the end of the service period of the cutting tool while machining. It is significant to provide a corresponding real-time varying damping to control this chatter, which directly influences accuracy and quality of productivity. This paper aims to review the literature related to the application of smart fluid to control vibration in metal cutting and also focused on the challenges involved in the implementation of active control system during machining process.

Smart dampers, which are used as semi-active and active dampers in metal cutting, were reviewed and the research studies carried out in the field of the magnetorheological (MR) damper were concentrated. In smart materials, MR fluids possess some disadvantages because of their sedimentation of iron particles, leakage and slow response time. To overcome these drawbacks, new MR materials such as MR foam, MR elastomers, MR gels and MR plastomers have been recommended and suggested. This review intents to throw light into available literature which exclusively deals with controlling chatter in metal cutting with the help of MR damping methods.

Using an MR damper popularly known for its semi-active damping characteristics is very adaptable and flexible in controlling chatter by providing damping to real-time amplitudes of tool vibration. In the past, many researchers have attempted to implement MR damper in metal cutting to control vibration and were successful. Various methods with the help of MR fluid are illustrated.

A new cutting tool is always well-defined and sharp at the onset of metal cutting process and gradually losses these properties as the machining process advances. Similarly, at the beginning of the machining process, amplitude of tool vibrations is considerably low and it increases gradually and peaks at the end of service period of cutting tool while machining. Application of MR damper along with the working methodology in metal cutting is presented, challenges met are analyzed and a scope for development is reviewed.

This study provides corresponding real-time varying damping to control tool vibration which directly influences accuracy and quality of productivity. Using an MR damper popularly known for its semi-active damping characteristics is very adaptable and flexible in controlling chatter by providing damping to real-time amplitudes of tool vibration.

This study attempts to implement smart damper in metal cutting to control vibrations.

It is significant to provide corresponding real-time varying damping to control tool vibration which directly influences accuracy and quality of productivity.

A magnetorheological knee prosthesis is presented that automatically adapts knee damping to the gait of the amputee using only local sensing of knee force, torque, and position. To assess the clinical effects of the user‐adaptive knee prosthesis, kinematic gait data were collected on four unilateral trans‐femoral amputees. Using the user‐adaptive knee and a conventional, non‐adaptive knee, gait kinematics were evaluated on both affected and unaffected sides. Results were compared to the kinematics of 12 age, weight and height matched normals. We find that the user‐adaptive knee successfully controls early stance damping, enabling amputee to undergo biologically‐realistic, early stance knee flexion. These results indicate that a user‐adaptive control scheme and local mechanical sensing are all that is required for amputees to walk with an increased level of biological realism compared to mechanically passive prosthetic systems.

Nowadays, in building structures, dampers are connected to the building structure to reduce the damages caused by seismicity in addition to enhancing structural stability, and to connect dampers with the structure, joints are used. In this paper, three different configurations of double-lap joints were designed, developed and tested.

This paper aims to analyze three different categories of double-lap single-bolted joints that are used in connecting dampers with concrete and steel frame structures. These joints were designed and tested using computational, numerical and experimental methods. The studies were conducted to examine the reactions of the joints during loading conditions and to select the best joints for the structures that allow easy maintenance of the dampers and also withstand structural deformation when the damper is active during seismicity. Also, a computational analysis was performed on the designed joints integrated with the M25 concrete beam column junction. In this investigation, experimental study was carried out in addition to numerical and computational methods during cyclic load.

It was observed from the result that during deformation the double-base multiplate lap joint was suitable for buildings because the deformations on the joint base was negligible when compared with other joints. From the computational analysis, it was revealed that the three double joints while integrated with the beam column junction of M25 grade concrete structure, the damages induced by the double-base multiplate joint was negligible when compared with other two joints used in this study.

To prevent the collapse of the building during seismicity, dampers are used and further connecting the damper with the building structures, joints are used. In this paper, three double-lap joints in different design configuration were studied using computational, numerical and experimental techniques.

This paper aims to design and analyze a controlled magnetorheological damper-based ankle-foot prosthesis prototype.

The ankle-foot prostheses prototype is proposed using the lightweight three dimensional (3 D)-printed parts, MR damper and digital servomotor. Initially, the computer-aided design (CAD) model of the prosthetic foot, leaf spring, retention spring and the various connecting parts required to connect the pylon and damper actuator assemblies are designed using CAD software. Later, the fused deposition modeling 3 D printer-based technique prints a prosthetic foot and other connecting parts using Acrylonitrile Butadiene Styrene filament. The prototype consists of two control parts: the first part controls the MR actuator that absorbs the impacts during walking. The second part is the control of the electric actuator intended to generate the dorsiflexion and plantar flexion movements. Finally, the prototype is tested on a transtibial amputee under the supervision of a prosthetist.

The ANalysis SYStems software-based analysis has shown that the prosthetic foot has a factor of safety values between 4.7 and 8.7 for heel strike, mid-swing and toe-off; hence, it is safe from mechanical failure. The designed MR damper-based ankle-foot prosthesis prototype is tested on an amputee for a level-ground walk; he felt comfortable compared to his passive prosthesis.

The design of an MR damper-based prosthesis prototype offers a better dynamic range for locomotion than passive prostheses. It reduces the injuries and provides relief to the transtibial amputees.

This paper aims to introduce a high-temperature grease design method assisted by back propagation neural network (BPNN) and verify its application value.

First, the grease data sets were built by sorting out the base data of greases in a large number of literatures and textbooks. Second, the BPNN model was built, trained and tested. Then, the optimized BPNN model was used to search the unknown data space and find the composition of greases with excellent high-temperature performance. Finally, a grease was prepared according to the selected composition predicted by the model and the high-temperature physicochemical performance, high-temperature stability and tribological properties under different friction conditions were investigated.

Through high temperature tribology experiments, thermal gravimetric analysis and differential scanning calorimetry experiments, it is proved that the high temperature grease prepared based on BPNN has good high-temperature performance.

To the best of the authors’ knowledge, a new method of designing and exploring high-temperature greases is successfully proposed, which is useful and important for the industrial applications.

The objective of this paper is to develop a fast modelling technique for predicting magneto-rheological fluid damper behaviour under impact loading applications.

The adaptive neuro-fuzzy inference system (ANFIS) technique was adopted to predict the behaviour of a magneto-rheological fluid (MRF) damper through experimental characterisation data. In this study, an MRF damper manufactured by Lord Corporation was used for characterisation using an impact pendulum test rig. The experimental characterisation was carried out with various impact energies and constant input currents applied to the MRF damper.

This research provided a fast modelling technique with relatively less error in predicting MRF damper behaviour for the development of control strategies. Accordingly, the ANFIS model was able to predict MRF damper behaviour under impact loading and showed better performance than the modified Bouc–Wen model.

This study only focused on modelling technique for a single type of MRF damper used for impact loading applications. It is possible for other applications, such as cyclic loading, random loadings and system identification, to be studied in future experiments.

Future researchers could apply the ANFIS model as an actuator model for the development of control strategies and analyse the control performance. The model also can be replicated in other industries with minor modifications to suit different needs.

The adverse effects of temperature on the lubricating properties of nano magnetorheological grease are reduced by applying of a magnetic field.

Nano magnetorheological grease was prepared via a thermal water bath with stirring. The lubricating properties of the grease were investigated at different temperatures. Then the lubricity of the prepared nano magnetorheological grease was investigated under the effect of thermomagnetic coupling.

As the temperature rises, the coefficient of friction of grease lubrication gradually increases, surface wear gradually increases and lubrication performance gradually decreases. Compared with grease, magnetorheological grease has a decreased coefficient of friction and enhanced lubrication effect under the action of a magnetic field at different temperatures.

A lubrication method using a magnetic field to reduce the effect of temperature is established, thereby providing new ideas for lubrication design under a wide range of temperature conditions.

In order to make sure of the safety of a long-span suspension bridge under earthquake action, this paper aims to study the traveling wave effect of the bridge under multi-support excitation and optimize the semi-active control schemes based on magneto-rheological (MR) dampers considering reference index as well as economical efficiency.

The finite element model of the long-span suspension bridge is established in MATLAB and ANSYS software, which includes different input currents and semi-active control conditions. Six apparent wave velocities are used to conduct non-linear time history analysis in order to consider the seismic response influence in primary members under traveling wave effect. The parameters α and β, which are key parameters of classical linear optimal control algorithm, are optimized and analyzed taking into account five different combinations to obtain the optimal control scheme.

When the apparent wave velocity is relatively small, the influence on the structural response is oscillatory. Along with the increase of the apparent wave velocity, the structural response is gradually approaching the response under uniform excitation. Semi-active control strategy based on MR dampers not only restrains the top displacement of main towers and relative displacement between towers and girders, but also affects the control effect of internal forces. For classical linear optimal control algorithm, the values of two parameters (α and β) are 100 and 8 × 10–6 considering the optimal control effect and economical efficiency.

The emphasis of this study is the traveling wave effect of the triple-tower suspension bridge under multi-support excitation. Meanwhile, the optimized parameters of semi-active control schemes using MR dampers have been obtained, providing relevant references in improving the seismic performance of three-tower suspension bridge.

This study aims to reveal the temperature rise characteristic of magnetorheological (MR) fluid in a multi-disc MR clutch under slip condition, including the temperature distribution regularity and the impact factors.

Three-dimensional transient heat conduction equation for the MR fluid in the working gap was derived based on the heat transfer theory. Then, numerical simulation was conducted to analyze the temperature field of MR fluid. Furthermore, an experimental study was performed to explore the temperature distribution of the MR fluid in radial and circumferential directions, as well as the effects of disc groove, slip power and gap size on temperature rise characteristic of the MR fluid.

The results show that temperature appears to be largest in the center of the working gap and the temperature difference increases with the slip time. However, the temperature field in a circumferential direction is basically the same, but it presents slightly lower in the groove area. The temperature of the MR fluid increases linearly with the slip time and the rise rate increases with the slip power. Moreover, the temperature rise value decreases with the increase of gap size.

In this paper, the temperature gradients, both in radial and circumferential directions, are experimentally measured going beyond the estimation by computer simulations. In addition, the factors that influence the temperature rise characteristic of MR fluid were fully analyzed. The results could provide a reliable basis for the development of cooling technology for high-power MR devices.

The purpose of this paper is to elaborate upon the mathematical model of coupled electromagnetic, fluid dynamic and motion phenomena that will allow for investigation of the magnetic hysteresis influence on the axial symmetry magnetorheological fluid (MRF) clutch operation.

To solve the partial differential equations describing magnetic vector and fluid velocity potential distributions in axial symmetry MRF electromechanical transducers the finite‐element methods have been applied. To solve model equations in the time domain, the time stepping method have been adopted. To introduce magnetic hysteresis phenomenon to presented approach the Jiles‐Atherton model have been applied. The physical properties of MRFs have been modeled by means of the Bingham model. Owing to high nonlinearity of the considered problem to solve obtained matrix equations systems the iterative Newton‐Raphson combined with the block over relaxation method have been applied.

The proposed model of coupled phenomena and the elaborated algorithm for solving the nonlinear model equations can be successfully applied in the analysis of transients in the MRF transducers taking fluid dynamics and magnetic hysteresis into account. Comparison of the measured and calculated clutch characteristics proves the model accuracy. Moreover, it has been shown that the residual magnetic flux density of the ferromagnetic core has significant impact on both to yield stresses forming in MRFs as well as the torque in disengagement clutch operation.

Development of the method for analysis of transients electromagnetic and fluid flow phenomena in MRF transducers taking magnetic hysteresis, electric circuits and motion into account. The presented approach is universal and can be successfully applied in other types of MRF electromechanical transducers such as clutch, brakes, rotary and linear dampers.