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- Suspension systems are vital in determining the vehicle's response to various driving conditions, including braking maneuvers. This paper aims to investigate the impact of suspension characteristics on braking performance, to improve overall driving safety and comfort. This study used a sedan car model that drives on a straight track and cornering. Modeling was carried out using the Altair Motion view 2021 with two test cases: braking tests on a straight track and brake-in-turn tests with speeds of 30 km/h and 60 km/h. The results showed that in braking tests on a straight track, increasing suspension stiffness reduces longitudinal slip on the rear wheels and suspension travel on both the front and rear wheels. This reduction in longitudinal slip results in the actual wheel speed value getting closer to the wheel rotational speed. While in the brake-in-turn test, increasing stiffness affects the lateral slip of the rear wheels. This improves driving safety because it reduces the potential for the car to skid. [ABSTRACT FROM AUTHOR]

Featured Application: The results are applicable to the configuration of design parameters of pneumatic brake valves. The proposed conceptual solution for the valve's differential part has implementation potential. The analyses meet the trend of increasing the speed of pneumatic braking systems. Pneumatic systems, despite being slower than hydraulic systems, pose less environmental risk during use or failure. Motivation: To increase the efficiency of the brake valve by adding a corrective member. Background: The speed of response and smooth transition between modes of operation in the braking system are the primary research questions. Objective and research question: Will the optimal selection of the input parameters of the differentiating part of a conceptual brake valve ensure the speed of operation and enable a smooth transition from the accelerating mode to the tracking mode? Methods: The mathematical model of the differentiating part of the brake valve uses the lumped method, and the solution was obtained by numerical means. Results: Within the assumed range of variation of spring stiffness and control piston bore throughput, the distribution maps of action times and piston lift were determined, and the optimal configuration of the analyzed input parameters was obtained by a genetic algorithm. Future research: future activities will focus on the development of a system of smooth variation of the throughput of the connecting chamber of the differential part of the valve. Conclusions: The determined maps of functional parameter distributions are the basis for the selection of components of the braking system; optimization indicates the directions of modification of the valve in order to obtain an acceptable performance system. [ABSTRACT FROM AUTHOR]

In the evolving landscape of digital technology, the concept of digital twinning has emerged as one of the most important innovations. Digital twinning, characterized by a one‐to‐one correlation with physical structures in a digital environment, has become an important tool in transferring physical dynamics into digital replicas. This platform, integrating advanced sensor technologies and analytical tools, enables a comprehensive monitoring, diagnosis, and optimization concept. The present research focuses on the application of digital twinning in addressing the complex challenge of managing fault types in freight car brakes. A Digital Twin (DT) model of a freight car braking system is developed that forms the basis for an innovative approach to fault classification. This approach leverages the ability of the DT to emulate and analyze the behavior of the braking system under different conditions. The effectiveness of the proposed method is evaluated through extensive testing and analysis with an experimental data set. The results show that the method is able to accurately diagnose different types of faults. This represents a significant advance in the field of freight car brake system diagnosis. [ABSTRACT FROM AUTHOR]

Copyright of Rolling Stock (1002-7602) is the property of Rolling Stock Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For any type of existing vehicle, one of the most important systems in its structure is the braking system. It is also the main safety element, which stops the vehicle by converting kinetic energy into heat. For constructive reasons and thermal efficiency, ventilated discs are the most widespread and used in industry, therefore, they will also be used in this scientific paper. Ventilated discs are often used to automobile application because of their higher heat dissipation. The purpose of this work is to create a thermally efficient design for ventilated brake discs by adopting two different designs from a constructive point of view. A special importance was also for the brake disc material, initially a semi-metallic material was chosen, being the most used for discs, later the ceramic material was also chosen, which has improved thermal properties. The design variant for the brake disc, to which the disc material and the thermal shield are added, lead to a significant improvement from a thermal point of view, which was also the main objective of this work. Ultimately, this study underscores the pivotal role of innovative design strategies and material selection in advancing the thermal efficiency of ventilated brake discs, thus contributing to the broader landscape of automotive safety and performance engineering. [ABSTRACT FROM AUTHOR]

Copyright of Rolling Stock (1002-7602) is the property of Rolling Stock Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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. [ABSTRACT FROM AUTHOR]

The brake system must be reliable and display unchanging action throughout its use, as it guards the health and life of many people. Properly matched friction pair, a drum, and a brake pad have a great impact on these factors. The brake pads are far more complex components. New technologies make it possible to develop materials with various compositions and different proportions and connect them permanently in fully controllable processes. This elaboration shows that all these factors have a greater or lesser impact on the coefficient of friction, resistance to friction wear and high temperature, and the brake pad’s operating life. The friction materials are required to provide a stable coefficient of friction and a low wear rate at various operating speeds, pressures, temperatures, and environmental conditions. The aim of this work is therefore to investigate the possibility of using a Finite Element Analysis (FEA) approach to evaluate the braking performance of a heavy-duty elevator with different non-conventional pad materials including Composite Carbon fiber reinforced, Composite Epoxy SMC and SiC (silicon carbide). The results show that the performance of SiC (silicon carbide) is better than two other materials. In the braking system with SiC, the required time for stoppage of the system is lower than two other materials.

Copyright of Rolling Stock (1002-7602) is the property of Rolling Stock Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The reliability of monorail crane braking system has an important influence on the braking safety. The high speed and heavy load operation poses a great challenge to the braking safety, and it is necessary to evaluate its braking reliability accurately and efficiently. Firstly, the dynamic performance and thermal-mechanical coupling characteristics of high-speed and heavy-load monorail crane under different braking parameters were analyzed. Secondly, the random response model of braking distance and braking temperature was established by combining the design of experiment method (DoE) and Dendrite Net (DD). Finally, the high-order moment saddlepoint approximation (SPA) method was used to evaluate the emergency braking reliability of the monorail crane. The results can provide a reference for the selection of key parameters and the evaluation of braking safety of the monorail crane braking system under high-speed and heavy-load conditions. [ABSTRACT FROM AUTHOR]

A braking system in a vehicle has a very important role in maintaining the safety of drivers and passengers, and preventing accidents. The brake system functions to reduce speed (slow down) and stop the vehicle. A good braking system provides safety and comfort for the drivers. Therefore, it is necessary to design the right braking system for "Sakera" car. In this study, an analysis and calculation of the braking system was carried out to determine the required braking force at a speed of 50 km/hour and other speeds in a distance of 15 m. The data taken in this study was the specification of the braking system used in the Sakera car. The braking system analysis was carried out on flat roads with varying speeds, namely 30 km/h, 35 km/h, 40 km/h, 45 km/h, and 50 km/h with a distance of 15 m for braking. The conclusions of the analysis were obtained, namely the greater the speed of Sakera's car, the greater the braking force to stop the car, the hydraulic pressure on the hose, and the force of the driver's feet, as well as the braking force needed on road conditions with a slope angle of 20°, which is 839.362 N. [ABSTRACT FROM AUTHOR]

In the world of motorsports engineering, improving brake performance is a crucial goal. One significant factor that affects this performance is the increase in brake disc temperature due to reduced cooling airflow, a phenomenon called "blanking". This temperature increase also impacts the rim and the air inside the tire, causing changes in tire temperature and pressure, which affects the vehicle's performance. Properly adjusting the brake blanking can be essential to keep the tire running at the right temperature, resulting in maximization of the performance on track. To address this complex problem, this study describes the problem of cooling brake discs, and this problem is then used as an opportunity to introduce a new variable in order to optimize the performance of the vehicle. By changing the thermal evolution of the brake disc, through the blanking, it can change a large percentage of heat that heats the tire. When combining an existing brake model in the literature with a tire thermal model in a co-platform simulation, it was seen that it is possible to work these two models together with the aim of being able to obtain the prediction of the optimal blanking value to be adopted before proceeding on track, thus saving time and costs. [ABSTRACT FROM AUTHOR]

Copyright of Rolling Stock (1002-7602) is the property of Rolling Stock Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The brake system must be reliable and display unchanging action throughout its use, as it guards the health and life of many people. Properly matched friction pair, a drum, and a brake pad have a great impact on these factors. The brake pads are far more complex components. New technologies make it possible to develop materials with various compositions and different proportions and connect them permanently in fully controllable processes. This elaboration shows that all these factors have a greater or lesser impact on the coefficient of friction, resistance to friction wear and high temperature, and the brake pad's operating life. The friction materials are required to provide a stable coefficient of friction and a low wear rate at various operating speeds, pressures, temperatures, and environmental conditions. The aim of this work is therefore to investigate the possibility of using a Finite Element Analysis (FEA) approach to evaluate the braking performance of a heavy-duty elevator with different nonconventional pad materials including Composite Carbon fiber reinforced, Composite Epoxy SMC and SiC (silicon carbide). The results show that the performance of SiC (silicon carbide) is better than two other materials. In the braking system with SiC, the required time for stoppage of the system is lower than two other materials. [ABSTRACT FROM AUTHOR]

In the world of motorsports engineering, improving brake performance is a crucial goal. One significant factor that affects this performance is the increase in brake disc temperature due to reduced cooling airflow, a phenomenon called “blanking”. This temperature increase also impacts the rim and the air inside the tire, causing changes in tire temperature and pressure, which affects the vehicle’s performance. Properly adjusting the brake blanking can be essential to keep the tire running at the right temperature, resulting in maximization of the performance on track. To address this complex problem, this study describes the problem of cooling brake discs, and this problem is then used as an opportunity to introduce a new variable in order to optimize the performance of the vehicle. By changing the thermal evolution of the brake disc, through the blanking, it can change a large percentage of heat that heats the tire. When combining an existing brake model in the literature with a tire thermal model in a co-platform simulation, it was seen that it is possible to work these two models together with the aim of being able to obtain the prediction of the optimal blanking value to be adopted before proceeding on track, thus saving time and costs.

The problem of implementing the landing of a maneuverable aircraft by a pilot on an undamaged section of a runway of minimum length is considered. A method of landing the aircraft is proposed, including movement along the landing glide path with minimum speeds and angles of attack of 12-14 deg., the release of the landing parachute before touching the runway with the main wheels so that by the time the wheels touch the ground, the parachute fully opens, lowering the nose wheel and subsequent braking with maximum deceleration. A simplified mathematical model is considered that makes it possible to estimate the length of the run and the results of calculations for various parameters of the landing mass and the height of the release of the braking parachute. The results of such landings in flight tests are presented and compared with the results of calculated estimates. The calculated and experimental results obtained allow us to speak about the fundamental feasibility of the task of landing on a runway section limited in length.

Motivation: To increase the efficiency of the brake valve by adding a corrective member. Background: The speed of response and smooth transition between modes of operation in the braking system are the primary research questions. Objective and research question: Will the optimal selection of the input parameters of the differentiating part of a conceptual brake valve ensure the speed of operation and enable a smooth transition from the accelerating mode to the tracking mode? Methods: The mathematical model of the differentiating part of the brake valve uses the lumped method, and the solution was obtained by numerical means. Results: Within the assumed range of variation of spring stiffness and control piston bore throughput, the distribution maps of action times and piston lift were determined, and the optimal configuration of the analyzed input parameters was obtained by a genetic algorithm. Future research: future activities will focus on the development of a system of smooth variation of the throughput of the connecting chamber of the differential part of the valve. Conclusions: The determined maps of functional parameter distributions are the basis for the selection of components of the braking system; optimization indicates the directions of modification of the valve in order to obtain an acceptable performance system.

The authors of this manuscript present the development of a braking system with friction material base WC-Cu coating for the electric vehicle. This manuscript follows on from the original development of an AGV multi-disc braking system and an experimental investigation of the friction factor of WC-Cu coatings. In addition to developing the mechanical elements and construction of the electric vehicle, the tribological parameters of three samples of the steel substrate, the C45 with WC-Cu coating, were investigated in the tribological laboratory. A metallic coating of the WC-Cu base was applied on the C45 steel substrate using electro-spark deposition coating technology. The experiment used three samples with different percentage ratios of chemical elements in the coating structure. The tribometer working on a “Ball on Plate” principle was an investigation of the friction factor of all samples during the experiment. Subsequently, the surface of the samples was modified structure WC-Cu with laser technology. The microhardness of modified and unmodified coatings according to the Vickers methodology was investigated in the next stage. At the end of the experimental investigation, a braking simulation was created in the programming environment of the Matlab® software, considering all driving resistances. The researchers also focused on the simulation of heat conduction during braking for some considered driving modes with braking on a level and with a 20% slope roadway. The simulation of heat flow was carried out in the Matlab® programming environment using the Fourier partial differential equation for non-stationary heat conduction.

The study of the tribological behavior of the braking system in auto vehicles requires knowing the characteristics of the materials in contact with the friction pair, brake disc–pads, in the work process. Analysis of the materials is necessary because the wear process depends on the friction pair, and brake disk–pads, respectively on the parameters of the work process (rotational speed, pressing force, traffic conditions, etc.). The material of the brake discs is generally the same gray cast iron, but the brake pads can be semi–metallic (combination of metallic and non–metallic materials, all bonded with a special resin), organic materials (non–metallic components such as glass, rubber, and kevlar all joined with the help of a resin) and ceramic (they have only ceramic material as a composition, rarely have small copper particles). The purpose of the work is to know the crystalline structure and the mechanical properties of the brake pad materials, through specific analyses, with important implications on the friction and wear behavior. [ABSTRACT FROM AUTHOR]

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.

Copyright of Journal of Vibration, Measurement & Diagnosis is the property of Nanjing Hangkong Daxue and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Interdependence is an inherent feature of the cyber-physical system. Small damage to one component in the system may affect several other components, leading to a series of failures, thus collapsing the entire system. Therefore, the system failure is often caused by the failure of one or more components. In order to solve this problem, this paper focuses on a failure propagation probability prediction method for complex electromechanical systems, considering component states and dependencies between components. Firstly, the key component set in the system is determined based on the reliability measure. Considering the three coupling mechanisms of mechanical, electrical, and information, a topology network model of the system is constructed. Secondly, based on the topology network model and fault data, the calculation method of influence degree between components is proposed. Three state parameters are used to express the risk point state of each component in the system through mathematical representation, and the correlation coefficient between the risk point state parameters is calculated and measured based on the uncertainty evaluation. Then, the influence matrix between the system risk points is constructed, and the fault sequence is predicted by using the prediction function of an Artificial Neural Network (ANN) to obtain the fault propagation probability. Finally, the method is applied to the rail train braking system, which verifies that the proposed method is feasible and effective. [ABSTRACT FROM AUTHOR]

Copyright of Rolling Stock (1002-7602) is the property of Rolling Stock Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A method is developed for calculating the output characteristics of a drum brake with floating shoes on the basis of the system configuration, the dimensions of the components, the frictional coefficient in contact zones of the linings, and the driving forces on the shoes. By this means, the structural parameters of the brake, their inference on the braking torque, the effectiveness of the shoes, the reaction forces in the shoe supports, and the maximum pressure on the frictional linings may be determined at the design stage. As an illustration, brake mechanisms with a single shoe and with servo amplification are calculated. [ABSTRACT FROM AUTHOR]

This paper concern the design and control of a wind energy conversion system regulating generator phase's currents, voltages, and batteries charging voltage using barking systems and AC–DC converter. Indeed, the braking system permit the regulation of the generator's angular speed and electromotives forces magnitude, and the AC–DC converter permit the regulation of the phase's voltages, currents, and the batteries charging voltage. This method is suitable for permanent magnet axial flux synchronous generators and for Insulated Gate Bipolar Transistor converters (IGBT). In addition, we propose an innovative strategy to push the problem of adding an impedance matching transformer to minimize the over-current effect caused by the sudden variation of the voltage at the generator inductor using the AC–DC converter. It offers the advantage of power chain cost reduction and the improvement of its performances. The overall model of the power chain is implemented under the simulation environment MATLAB-Sumilink for performances analysis of studied structure. [ABSTRACT FROM AUTHOR]