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AbstractIn this paper, the potential of using a head-up display (HUD) in the connected environment to improve a vehicle’s running comfort and pedestrian safety is tested, by providing warning information to drivers in advance. To achieve this objective, driving simulation technology is used to construct the connected environment and develop the HUD, and the effectiveness of the system is then tested. Specifically, thirty-four participants were recruited to conduct driving simulation experiments in six scenarios: three warning display types (Baseline/Head-down display/Head-up display) combined with two weather conditions (clear weather/foggy weather). The effects of the three different warning display types on braking risk-avoidance strategy were studied by comparing the drivers’ performance during the perception and decision stage (position of accelerator-pedal release, position of first braking), the risk-avoidance manipulation stage (maximum deceleration, braking distance) and the risk-avoidance result stage (minimum collision distance, position of minimum speed). The influences of weather conditions and driver attributes were also considered. When the HUD warnings were activated, drivers started to decelerate further away from pedestrians, with a more stable and moderate deceleration process and a greater safety margin between the vehicle and the pedestrians. Using HUD warnings in foggy conditions improved drivers’ perception and decision abilities, this study confirmed the great benefits that HUD warnings in the connected environment can bring to traffic safety, especially under risky situations and inclement weathers. The research results provide a reference for the more humanized and rationalized optimization design of these warning systems. [ABSTRACT FROM AUTHOR]

The electro-pneumatic braking system with ON/OFF solenoid valves has been widely used in trains due to its advantages and superiority. The undesirable impact of the thermal effect on the electro-pneumatic braking system leads to frequent valve switching, degradation of the pressure tracking performance and sometimes instability. This article presents an adaptive model predictive control approach to solve the pressure control problem under temperature uncertainty based on a switched unscented Kalman filter. First, a nonlinear switched dynamical model with the uncertain temperature parameter is derived for the electro-pneumatic braking system by comprehensively integrating its nonlinear, discontinuous dynamics and thermal effect. Using a switched unscented Kalman filter on the presented model of the system, the temperature parameter is accurately estimated to improve the model's accuracy. Based on the corrected system model and the designed adaptive model predictive control method, the pressure tracking performance and the valves' switchings of the electro-pneumatic braking system are improved, and the stability is guaranteed. The simulations and the experiments conducted for a braking system prototype confirm the performance validity of the proposed method. • A switched UKF is designed to account for the hybrid characteristics of the braking system. • An adaptive hybrid MPC is proposed to achieve optimal pressure tracking performance while minimizing the number of valve switches. • The stability of the closed-loop system is rigorously analyzed using Lyapunov theory. [ABSTRACT FROM AUTHOR]

Copyright of China Rubber Industry is the property of Editorial Office of China Rubber Industry 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 China Rubber Industry is the property of Editorial Office of China Rubber Industry 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 paper deals with the design of a calibration device for measuring the residual torque of the vehicle brake. It informs about the problems and purpose of the brakes, requirements placed on the brake system, and the design of vehicle brake systems. The practical part of the research contains the design of four versions of the calibration device and the 3D model of the proposed calibration device. There is also a new calibration methodology and calculation of the theoretical fault of the calibration device. An analysis and comparison of the original and new torque sensor calibration methods are presented at the end of this paper. By comparing the original and new calibration methods, it was revealed that the deviations from the required torque value compared to the original calibration version decreased from an average value of 0.154 Nm to 0.0047 Nm, and the variance of the measured values decreased on average from 0.00276 Nm to 2.07 × 10−6 Nm. The proposed new torque sensor calibration method has shown a positive contribution to the accuracy of torque sensor calibration, which as a result will significantly increase the reliability and accuracy of measuring the residual torque of automobile brakes and shorten the measurement time. [ABSTRACT FROM AUTHOR]

In this study, a theoretical model was established for longitudinal braking stability (LBS) of a lightweight liquid storage mini-track vehicle to investigate its behaviors. The influence of the tank liquid filling ratio (TLR), initial velocity (IV), and initial braking deceleration (IBD) on the LBS of the tracked vehicle was studied via FLUENT simulation. The simulation results showed that when the IV and the IBD were constant, the TLR significantly affected the braking efficiency. Conversely, when the TLR was 0.7, the braking efficiency decreased by 32%, resulting in the worst LBS. The braking efficiency at different IVs decreased by ~30% when using a constant IBD and TLR, and the braking stability exhibited little difference. Further, the braking efficiency decreased noticeably with increasing IBD; meanwhile, the braking longitudinal stability worsened. When the IBD was increased to 5 m⋅s−2, the braking efficiency decreased by 48.4%. The road experiment showed that when the tracked vehicle was accelerated and braked under limit conditions, the stability requirements were met. Finally, by combining the simulation and road experiment, the driving parameters of the tracked vehicle that could satisfy the LBS were obtained. [ABSTRACT FROM AUTHOR]

The development of electric vehicles (EVs) has been incremental because EVs satisfy a significant demand for energy sources. Electronic control unit (ECU) is an important component that processes the electric signals received from various sensors for generating the control signals for the actuators. Automotive control systems were initially operated manually throughout the automotive revolution based on the responses of input signals received from ECUs and drivers. Most of the functions in EV are controlled by the ECU and every ECU consumes power at all times even if it is not in use. The larger power consumption of passive ECUs like adaptive lighting systems (ALS), automatic wiper systems (AWS) brake light systems (BLS), etc., affect the life of ECUs and the range of EVs. This article is primarily concerned with limiting power consumption by switching the power supply to the passive ECUs based on their requirements. Hence, to achieve the objective, the intelligent zone (i-zone) based master ECU is triggered to activate the slave ECUs. Designing suites including Proteus and KiCAD were used for designing the circuits including master as well as slave ECU. This prototype is built using three secondary ECUs such as ALS & AWS and BLS which are controlled using i-zone-based master ECU. The performance of this implemented design is evaluated, and it is discovered that almost 40% of the battery consumption is reduced. This i-zone-based master ECU and all its slave ECUs manage power while ensuring the safety and reliability of EVs. [ABSTRACT FROM AUTHOR]

High risk of braking easily causes more safety accidents. In this paper, the driving experiments on G350 Gengda‐Yingxiu section containing continuous downhill tunnel group. Three‐axle trucks under standard load and overload conditions were considered. The research proposes a method for ensuring safe truck driving on continuous downhill sections of mountain roads based on the rise in brake drum temperature. The study collects data on brake drum temperature and braking duration from an experimental vehicle under the coupling action of human‐vehicle‐road‐environment. Through comparative analysis, theoretical derivation, and model construction, conclusions are drawn. The results indicate that the rise in brake drum temperature is influenced by the factors such as overload, alignment, road slope, and sections with bright and dark lines. The initial brake drum temperature, operating speed, and total vehicle mass are identified as the main controlling factors for the change in brake drum temperature. The study also demonstrates that water drenching can significantly reduce the rate of brake drum temperature rise, thereby ensuring driving safety. Furthermore, a model is constructed based on the relationship between brake drum temperature rise and various factors, which allows for the calculation of the corresponding safe slope length and average slope gradient. This model can be used for evaluating or designing overall load requirements. The research on brake drum temperature rise characteristics and braking behaviour under drenching conditions provides effective support for route design, traffic management, and the establishment of safety service facilities. [ABSTRACT FROM AUTHOR]

The integration of converter facilities into power systems has warranted a growing need to address the control interference phenomenon. In this study, we propose a facility-based approach to mitigate the control interference between adjacent high-voltage direct current (HVDC) units in a multi-infeed HVDC system. The proposed method uses a series braking resistor (SeBR) as a preventive measure to restore control when a fault occurs in one HVDC unit within a multi-infeed HVDC system, thereby enabling stable operation of adjacent HVDC units. The developed SeBR model incorporates an inductor component and is divided into Stages 1 and 2 to overcome the frequency reduction issue associated with the long-term deployment of conventional R-based SeBRs. Additionally, if the fault continues to affect the control of adjacent HVDC units despite the application of a blocking stage in the faulted HVDC unit, switch controller logic circuits are designed considering the deployment of Stage 2 of the proposed SeBR. The effectiveness of the proposed SeBR is validated based on the detailed modeling and verification of actual HVDC systems via a case study. The results validate the superior performance of the proposed SeBR over other methods in ensuring a continuous stable operation of the system. [ABSTRACT FROM AUTHOR]

In response to the fact that autonomous vehicles cannot avoid obstacles by emergency braking alone, this paper proposes an active collision avoidance method for autonomous vehicles based on model predictive control (MPC). The method includes trajectory tracking, adaptive cruise control (ACC), and active obstacle avoidance under high vehicle speed. Firstly, an MPC-based trajectory tracking controller is designed based on the vehicle dynamics model. Then, the MPC was combined with ACC to design the control strategies for vehicle braking to avoid collisions. Additionally, active steering for collision avoidance was developed based on the safety distance model. Finally, considering the distance between the vehicle and the obstacle and the relative speed, an obstacle avoidance function is constructed. A path planning controller based on nonlinear model predictive control (NMPC) is designed. In addition, the alternating direction multiplier method (ADMM) is used to accelerate the solution process and further ensure the safety of the obstacle avoidance process. The proposed algorithm is tested on the Simulink and CarSim co-simulation platform in both static and dynamic obstacle scenarios. Results show that the method effectively achieves collision avoidance through braking. It also demonstrates good stability and robustness in steering to avoid collisions at high speeds. The experiments confirm that the vehicle can return to the desired path after avoiding obstacles, verifying the effectiveness of the algorithm. [ABSTRACT FROM AUTHOR]

We extend our model of magnetic braking (MB), driven by an α–Ω dynamo mechanism, from fully convective M-dwarfs (FCMDs) to explain the surface and internal spin |$P_\mathrm{spin}$| evolution of partly convective dwarfs (PCDs) starting from the disc-dispersal stage to the main-sequence turn-off. In our model, the spin of the core is governed by shear at the core-envelope boundary while the spin of the envelope is governed by MB and shear. We show that (1) the most massive FCMDs experience a stronger spin-down than PCDs and less massive FCMDs, (2) the stalled spin-down and enhanced activity of K-dwarfs and the pile-up of G-dwarfs older than a few Gyr are stellar-structure and MB-dependent, and weakly dependent on core-envelope coupling effects, (3) our expression of the core-envelope convergence time-scale |$\tau _{\text{converge}}(M_\ast , P_{\text{spin}})$| between a few 10 to 100 Myr strongly depends on stellar structure but weakly on MB strength and shear, such that fast and massive rotators achieve corotation earlier, (4) our estimates of the surface magnetic fields are in general agreement with observations and our wind mass loss evolution explains the weak winds from the solar analog |$\pi ^1$| UMa, and (5) with our model the massive young Sun hypothesis as a solution to the faint young Sun problem can likely be ruled out, because the maximum mass lost by winds from our Sun with our model is about an order of magnitude smaller than required to solve the problem. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) 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.)

Prolonged exposure to high-intensity noise environments in urban rail transit systems can negatively impact the health and work efficiency of drivers. However, there is a lack of comprehensive understanding of the noise pattern and, therefore, effective mitigation strategies. To control the noise in urban rail transit systems, this study proposes a comprehensive noise assessment framework, including metrics such as average sound pressure level, peak sound pressure level, percentile sound pressure levels, dynamic range, main frequency component, and cumulative time energy to evaluate the noise characteristics. We also employ a density-based spatial clustering of applications with noise (DBSCAN) method to identify the noise patterns with the evaluation of their hazard to urban rail transit drivers. The results have revealed that: (1) The equivalent continuous sound pressure level (Leq) in the cab of Lanzhou Urban Rail Transit Line 1 averages 87.12 dB, with a standard deviation of 8.52 dB, which reveals a high noise intensity with substantial fluctuations. (2) Ten noise patterns were identified, with frequencies varying from 14.47 Hz to 69.70 Hz and Leq varying from 60 dB to 115 dB. (3) The major noise sources from these patterns are inferred to be the train's mechanical systems, wheel–rail interaction, aerodynamic effects, and braking systems. Combined with the noise patterns and urban rail transit's operation environment, this study proposes tailored mitigation strategies for applications aimed at protecting drivers' hearing health, enhancing work efficiency, and ensuring driving safety. [ABSTRACT FROM AUTHOR]

The system parameters of the braking process of a rotary eddy current brake (RECB) exhibit time-varying characteristics and alternate transformations of the heat source (HS) and non-heat source (NHS) regions of the brake disc. A full-structure equivalent thermal network model for the RECB system is established, considering its physical structure. In addition, a calculation method is proposed to update the temperature of the rotating unit with a finite stepping distance. The method employs the transient process of electromagnetic thermal coupling on the brake disc, distinguishes between the thermal processes in the HS and NHS regions of the brake disc, and simulates the temperature distribution of the entire braking system. The proposed calculation method is verified via rig tests, and the effects of brake temperature rise on braking performance are assessed. The method can be used for optimal design, heat capacity analysis, and life analysis of brakes. [ABSTRACT FROM AUTHOR]

In long-term operation, the gradual degradation process of automotive friction pads significantly affects the expected performance of mechanical equipment. In addition, the intrinsic correlations between friction properties and the multi-stage degradation process have been mostly ignored, leading to less accurate prediction of results under multifactorial influences on working conditions. In this paper, we propose a novel prediction method using the CNN-BiLSTM-Att model to overcome the problem. The model uses CNN to extract the friction features in the processed data, and combines with BiLSTM to evaluate the time series features hidden in the friction data. To improve the prediction accuracy, the attention mechanism is fed into the proposed model, which has the advantage of automatically assigning appropriate weights to the hidden layer states to distinguish the importance of different data features. Compared with other machine learning algorithms, the method has high prediction accuracy and can provide reference for braking. [ABSTRACT FROM AUTHOR]

Rolling walkers are common walking aids for individuals with poor physical fitness or balance impairments. There is no doubt that rolling walkers are useful in assisting locomotion. On the other hand, it is arguable that walking with rolling walkers (WW) is effective for maintaining or restoring the nervous systems that are recruited during conventional walking (CW). This is because the differences and similarities of the neural control of these locomotion forms remain unknown. The purpose of the present study was to compare the neural control of WW and CW from the perspective of a split-belt adaptation paradigm and reveal how the adaptations that take place in WW and CW would affect each other. The anterior component of the ground reaction (braking) forces was measured during and after walking on a split-belt treadmill by 10 healthy subjects, and differences in the peak braking forces between the left and right sides were calculated as the index of the split-belt adaptation (the degree of asymmetry). The results demonstrated that (1) WW enabled subjects to respond to the split-belt condition immediately after its start as compared to CW; (2) the asymmetry movement pattern acquired by the split-belt adaptation in one gait mode (i.e., CW or WW) was less transferable to the other gait mode; (3) the asymmetry movement pattern acquired by the split-belt adaptation in CW was not completely washed out by subsequent execution in WW and vice versa. The results suggest unique control of WW and the specificity of neural control between WW and CW; use of the walkers is not necessarily appropriate as training for CW from the perspective of neural control. [ABSTRACT FROM AUTHOR]

To achieve precise prediction of the air pressure changes in the critical components of the air brake system, including brake pipes (BP), auxiliary reservoirs (AR), and brake cylinders (BC), this paper proposed a neural network-based air brake model developed from the brake application and release experimental data with different brake applications (50, 70, 100, and 150 kPa) conducted on a heavy haul train (HHT) test platform. The physical structures of the air brake system and the working mechanisms of a neural network are introduced, and the neural network-based air brake model scheme is presented by analysing the variation of air pressure within the air brake system under typical braking conditions (50 kPa). Besides, by comparing with other models, the superiority of the proposed model is verified, and the proposed model achieves higher computational efficiency, which increased by about 2900 times compared to the fluid dynamic model under the same conditions. Then, the model is applied to the calculation of the longitudinal dynamics of a 10,000-ton HHT, and the results demonstrate that the proposed model could serve as a promising tool for solving the braking excitation problem of longitudinal dynamics of trains and the study of intelligent braking control of trains. [ABSTRACT FROM AUTHOR]

The braking system of a motor vehicle is a multi‐material system, subjected to various aggressive conditions. Corrosion of the brake disc during stationary periods can determine the onset of a high adhesion force (stiction) capable of compromising the reliability of the braking system during vehicle motion. The purpose of this work is to study the effect of the introduction of Cu and Zn in the friction material composition. This effect was investigated through electrochemical measurements (electrochemical impedance spectroscopy, potentiodynamic polarization, and stiction tests), conducted using an electrochemical cell simulating the parking brake, complemented by the examination of the brake disc and pad surfaces and water absorption tests. The results suggest that porous components, like vermiculite, in the composite friction material led to high contact force. Moreover, 10 wt% of Cu in the friction material does not significantly affect its stiction behavior in our testing configuration. In contrast, 10 wt% Zn in the friction material significantly reduces the stiction propensity by acting with a complex synergistic mechanism combining physical and chemical shielding effects. [ABSTRACT FROM AUTHOR]

The critical speed of eddy current braking is a vital parameter in the design of eddy current braking devices. Currently, most simulations and experiments are used to determine the critical speed, which means a lot of time costs. This paper presents two laws of critical speed variation to help designers more quickly determine the critical speed of a particular eddy current braking device. At first, the structure and the critical speed principle of permanent magnet rotary eddy current brake (PMRECB) are described. Secondly, the finite element analysis is used to verify the accuracy of the two laws. Finally, the validity of the finite element model is confirmed by the eddy current braking test. [ABSTRACT FROM AUTHOR]

Taking a rear‐wheel drive pure electric vehicle as the research object, considering the safety during braking and improving energy recovery rate, a study was conducted on the distribution strategy of front and rear axle braking force. During the braking process, the feedback braking force of the motor and the hydraulic braking force with an electronic stability controller (ESC) were coordinated and controlled, to ensure that the total required braking force was met. A fuzzy logic controller has been designed, with three variables of battery state of charge, vehicle speed, and braking intensity as inputs, and a modified motor braking ratio as output variable to prevent wheel lockup. Using Cruise software, a co‐simulation model was established with Amesim and Simulink, and simulation validation was conducted on the braking process and cycling conditions. The simulation results showed that the brake recovery strategy based on fuzzy control can effectively improve the vehicle's control performance and energy recovery rate compared to the Economic Commission of Europe regulation. The NEDC (New European Driving Cycle) working condition improved by 10.41% and the CLTC‐P (China Light‐duty Vehicle Test Cycle‐passenger) working condition improved by 10.57%. Effectively improving power consumption per 100 km, NEDC decreased by 1.81% and CLTC‐P decreased by 2.62%. [ABSTRACT FROM AUTHOR]

In this article, a new control method is proposed for the stability of Electrical Vehicles (EVs) with 2-motor wheels. This control method provides an optimized limit for the torque levels that produced by the front and rear motors, proportional to the road surface condition, to prevent the vehicle from slipping. In addition, a fuzzy logic-based braking system is proposed to improve vehicle performance during deceleration. The vehicle is described by the model with three degrees of freedom, which provide good accuracy. The tires are modeled according to the magic formula. To evaluate the effectiveness of the proposed method, simulations were performed in the ©MATLAB. The conclusions show that the proposed control method can well maintain the steadiness of the EV on dry and slippery roads when driving straight, accelerating or decelerating, and turning. This will prevent the vehicle from slipping and locking the wheels. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) 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.)

With increasing attention being paid to electric vehicles, hybrid braking systems combining regenerative braking and conventional friction braking have become a hot research topic. Although some important advancements have been achieved in the field of hybrid braking system control, these have not been fully summarized. In order to fill this gap and provide a comprehensive perspective for other researchers, this paper surveys a wide range of research works reported in the literature on hybrid braking system control. We identify the advantages and limitations of existing hybrid brake control strategies via comparative analysis. Through analysis, we find that the control strategy used for brake torque distribution and braking systems' coordinated control in current hybrid braking systems are usually designed separately. In order to ensure braking stability, most of the current hybrid braking control strategies are designed relatively conservatively, and it is difficult to fully leverage the advantages of hybrid braking systems. Comprehensively considering the coordinated control of braking torque distribution and braking systems is a good research direction for hybrid braking control research. Overall, this survey summarizes the existing research relevant to hybrid brake control methods and also discusses the research challenges and new research directions. [ABSTRACT FROM AUTHOR]

The wheels of decelerating vehicles in braking mode roll with increased slip, up to complete lock-up, which is a negative phenomenon. This is effectively managed by the anti-lock braking system (ABS). However, in the course of braking, especially before the system activation, self-excited oscillatory processes with high amplitudes may occur, causing increased dynamic loads on the drive system. The paper studies the braking processes of a vehicle with an electromechanical individual traction drive in both electrodynamic regenerative and combined braking modes, utilizing the drive and the primary braking system. The theoretical framework is provided for identifying the self-excited oscillation onset conditions and developing a technique to detect wheel slips during braking to suppress these oscillations. To check the functionality of the wheel-slip observer in braking mode, the performance of the self-excited oscillation pulse suppression algorithm was studied in the MATLAB Simulink 2018b software package. The study results can be used to develop control systems equipped with the function of suppressing self-excited oscillations by vehicle motion. [ABSTRACT FROM AUTHOR]

Under what circumstances do paramilitary groups place limits on their use of political violence? This article considers why one of the most prominent paramilitary groups active during the "Troubles" in Northern Ireland, the Provisional IRA (PIRA), exercised restraint and limited their use of political violence, both in the lead up to, and in the wake of the Good Friday Agreement. It applies Busher, Holbrook, and Macklin's "internal brakes" typology to understand why despite the PIRA's proven capacity to sustain a campaign of armed violence for more than thirty years, they reined in on paramilitarism during the 1990s peace process. Through the lens of various brakes, the analysis identifies seven developments that were particularly salient in limiting the PIRA's use of armed violence. These developments included: a weakened capacity to continue their armed campaign, waning popular support, an opening of political opportunities, the need to maintain ties with strategically important non-violent allies, the gradual softening of out-group boundaries, the decommissioning process, as well as the creation of spaces for non-violent activism within the wider movement. This study's findings contribute to the scholarly debate on understanding how militant groups manage the parameters of their violence, highlighting several factors that may mitigate the risk of extremist views escalating to political violence. [ABSTRACT FROM AUTHOR]

As the synthesis, modularization, and integration of avionics systems increase, the interconnections between systems and equipment within subsystems become increasingly complex, posing risks to the safety and reliability of the integrated avionics system. To address the risk of fault propagation due to functional cascade failures in integrated avionics systems, this paper proposes a discrete dynamic fault propagation analysis method, which was applied to an all-electric braking system to assess its feasibility. First, the architectural features of the Distributed Integrated Modular Avionics system are summarized. Subsequently, the constructed system layer model is described, establishing the function–resource hierarchical architecture. Subsequently, the behavior of cascading failure propagation in discrete dynamic systems is analyzed by integrating the cascading failure analysis method from SAE ARP 4761A and considering the coupling characteristics between system properties and functions comprehensively. This approach facilitates the development of a cascading failure propagation model for DIMA based on discrete dynamic systems. Finally, by using the all-electric braking system under DIMA architecture as a case study, key Core Processing Modules and failure-prone functions are identified. The findings reveal that within this system, CPM2 and CPM6 are particularly susceptible to failure propagation, and the automatic brake function is notably vulnerable. Data show that the system's failure rate escalates markedly after 2 × 10 4 h of operation. Performing maintenance before reaching this threshold can further mitigate risks. This practice aligns with current international aircraft maintenance time regulations. The method proposed in this paper can be applied early in the allocation of DIMA resources to enhance security and support DIMA design. [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]

To further improve the braking energy recovery efficiency of battery electric vehicles and increase the range of the cars, this paper proposes a multi-mode switching braking energy recovery control strategy based on fuzzy control. The control strategy is divided into three modes: single-pedal energy recovery, coasting energy recovery, and conventional braking energy recovery. It takes the accelerator pedal and brake pedal opening as the switching conditions. It calculates the front and rear wheel braking ratio allocation coefficients and the motor braking ratio through fuzzy control to recover braking energy. The genetic algorithm (GA) is used to update the optimized affiliation function to optimize the motor braking allocation ratio through fuzzy control, and joint simulation is carried out based on the NEDC (New European Driving Cycle) and CLTC-P (China Light-duty Vehicle Test Cycle for Passenger vehicles) cycle conditions. The results show that the multi-mode braking energy recovery control strategy proposed in this paper improves the energy recovery rate and range contribution rate by 4% and 9.6%, respectively, and increases the range by 22.5 km under NEDC cycle conditions. It also improves the energy recovery rate and range contribution rate by 8.7% and 5.5%, respectively, and increases the range by 13 km under CLTC-P cycle conditions, which can effectively improve the energy recovery efficiency of the vehicle and increase the range of battery electric vehicles. [ABSTRACT FROM AUTHOR]

Energy and transport are the two largest contributors to carbon emissions. In recent years, the transport sector has made strides in reducing its carbon footprint by producing electric vehicles that emit zero carbon. This paper investigates the use of Fuel Cell Electric Vehicles (FCEVs) with a newly developed regenerative suspension module (RSM). The RSM uses an electromechanical mechanism to obtain regenerative electrical energy from the engine and is mounted to the passive suspension system. To determine the potential energy savings of the RSM module, a hydrogen fuel cell electric vehicle simulated under specific road geometries, speeds, and acceleration conditions. The simulation results indicate that the Regenerative Suspension Modules (RSM) mounted on each wheel of the FCEV generate 2.5 times more energy than the regenerative braking system. This result is evaluated as an increase in efficiency and range in electric vehicles. • This study aimed to investigate efficiency gains from adding an RSM to hydrogen fuel cell electric vehicles. • This is the first study in literature to integrate RSM into a Fuel Cell Electric Vehicle. • The charging efficiency of the FCEV is improved by the Regenerative Suspension Modules mounted on each wheel. • The FCEV's Regenerative Suspension Module mounted on each wheel generates 2.5 times more energy than regenerative braking. [ABSTRACT FROM AUTHOR]

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) 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 Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) 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.)

Motorcycles are efficient and flexible tools for short-trip transportation, but they feature static instability and lean while cornering. This characteristic increases the danger of overturning. This study proposes a system to brake a motorcycle safely in a turn. The optimal slip ratio decision model is used to generate the optimal value according to roll angle and vertical force. Given that the roll angle cannot be measured directly, a Kalman filter is used to estimate the roll angle via kinematic parameters, measured by inertial measurement unit. The PID controller adjusts the current slip ratio to follow the optimal slip ratio. Using the motorcycle dynamics model from BikeSim, a co-simulation platform is constructed in MATLAB/Simulink to verify the reliability of the designed brake system. The results show that, compared with a traditional brake controller, the proposed brake system can control the motorcycle braking process by autoregulating the optimal slip ratio in time, according to the kinematic parameters. Both brake performance and stability are well considered, which contributes to improving the safety of the motorcycle. This research work has certain reference value for the development of motorcycle active safety systems. [ABSTRACT FROM AUTHOR]

A coordinated control of front/rear traction, four-wheel independent braking, and an active roll control system is proposed in this paper to improve overall vehicle cornering performance. The control algorithm is structured in a hierarchical form: the supervisory controller is used to calculate the desired yaw rate and roll angle based on the driver input and vehicle states; the upper-level controller is utilized to decide the target longitudinal tire forces, yaw moment, and anti-roll moment based on the sliding mode control method; and the control allocator is used to optimally map the virtual control input to the control commands of specific actuators. Co-simulations of MATLAB/Simulink and CarSim were conducted to verify the performance enhancement of the proposed controller. The results suggest that the proposed controller can effectively enhance the driving performance in limit cornering while maintaining lateral stability, and it reduces tire usage, as indicated by the index of tire dissipation energy when compared to control methods such as AWD, AWD-ESC, and ICC. [ABSTRACT FROM AUTHOR]

The purpose of the article was to present the results of braking equipment testing and determination of the adequacy of compressed air production of the braking system when the train is loaded. Experimental tests of the braking system of TE33A diesel locomotive in a goods train are performed. According to the initial data the main parameters of the braking system in the empty and loaded train were evaluated. As a result of tests, and according to the calculated data, the dependences of the volume of the main reservoirs, and the dependences of the required compressor capacity, on the number of axles have been obtained. It has been established that the braking system operation in release modes for a 400-axle train corresponds to the operating conditions and the main requirements of the normative documents. [ABSTRACT FROM AUTHOR]

As a key component, the braking system is vital for ensuring safe and comfortable operation of trains moving at high speeds. Because the aerodynamic drag depends linearly on the square of the vehicle speed, plate braking has broad prospects for high-speed trains. The train body interface is altered by the plate opening, which causes a sudden change in the flow field around the train and deteriorates its aerodynamic performance. In this study, dynamic grid technology was used to realize plate opening, and an improved delayed detached eddy simulation (IDDES) was used to simulate the unsteady aerodynamic characteristics of trains during plate braking. The simulations and settings were verified using wind-tunnel test data. The effects of the plate motion on the aerodynamic performance of the train were clarified by analyzing the changes of the aerodynamic loads of the plate and the train body within 0.2 s for an opening plate and 1.8 s for an opened plate. The aerodynamic forces of the different cars were significantly different during the plate-opening process, especially near the maximal opening angle. In particular, for the middle car, the aerodynamic force depended on the number of plates. The plate opening caused lateral aerodynamic fluctuations in the car body, which caused the car body to shake laterally, especially the downstream car, and the degree of the fluctuation of the lateral force of the car body also depended on the number of plates. Owing to the airflow inertia, the aerodynamic drag of the plate at the end of the motion appeared as a pulse peak, and the peak value decreased downstream of the train. The opening of the plates caused the flow field above the roof to develop disordered downstream. Owing to the coupling and superposition of the downstream flow field, the aerodynamic drag of the first plate fluctuated slightly, whereas that of the downstream plate fluctuated significantly, likely affecting the normal operation of the equipment on the top of the train, such as air conditioning and pantograph. [ABSTRACT FROM AUTHOR]

The wheel set of a rail vehicle with a disc brake is the basic assembly of a rail vehicle exposed to abrasive wear. From the operational point of view, the wear process of the wheels and brake discs is uneven, which for the carrier involves switching off the vehicle, once when the maximum wear of the discs is reached and again when the wheels wear out. The process of both untying the wheel set from the bogie, dismantling the wheels and discs from the axle is a time-consuming and expensive process, which consequently affects the exclusion of the vehicle from planned traffic. In the article on the basis of brake disc wear results, 3 concepts of bogie management were proposed. The first concerns the bogie rotation, the second and third concepts concern the exchange of bogies with and without rotation. Using the MUZ multi-criteria programming method, the concepts were evaluated and the best one was selected taking into account the evaluation criteria. The aim of the article is to present concepts that reduce the wear of discs brake systems in a multi-unit traction unit using bogie migration under the vehicle. [ABSTRACT FROM AUTHOR]

Rear-end collisions between autonomous vehicles (AVs) and human-driven vehicles (HVs) represent critical scenarios in road networks. Few studies have focused on the scenarios where a HV hits an AV from behind (called a HV-AV collision). This paper aims to investigate the occurrence of HV-AV collisions in the stop-in-lane (SiL) scenario where a HV follows an AV. A humanlike brake control (HLBC) model is firstly proposed to simulate the driver brake control. The HLBC model considers human driving intention, vision-based expectancy, and certain inherent characteristics of human driving to achieve dynamic humanlike braking. Additionally, the joint distribution of off-road-glance and time-headway is originally introduced to simulate the glance distraction of drivers during their dynamic vehicle control. Sequentially, we apply the HLBC model to the SiL scenario to investigate how the HV-AV collision probability changes with respect to various dynamic driving parameters. The results of the case study provide a thorough understanding of the dynamic driving conditions that lead to HV-AV collisions and pave the way for identifying practical countermeasures to improve the road safety involving AVs. [ABSTRACT FROM AUTHOR]

Virtual coupling of railway trains is an emerging technology that has the potential to significantly increase railway operational efficiency by reducing the train following distance from absolute braking distances to relative braking distances. Current research in this topic is mainly focused on passenger trains and uses distance-based headways. This paper studied virtual coupling for heavy haul freight trains and demonstrated that the distance headway scheme was challenging and sometimes impractical for heavy haul trains to achieve virtual coupling. A time-based headway scheme was then proposed to set the follower train to be a certain time behind the schedule of the leader train rather than a distance headway. The time-based headway required the follower train to reproduce the leader train's operational status at the same track location. This also allowed the follower train to copy any optimized train driving strategies from the leader train. Demonstrative simulations were carried out without the consideration of communication errors and train localization errors. The results show that a conventional distance headway simulation had maximum distance and speed errors of 716 m (36%, reference 2 km) and 24 km/h (66%, reference 36 km/h), respectively. A time-based headway simulation reduced the maximum distance and speed errors to 0.07 m (0%, reference 2 km) and 0.1 km/h (9%, reference 1.18 km/h), respectively. [ABSTRACT FROM AUTHOR]

Recent research has extensively examined in-vehicle display designs for supporting the operation of driving automation. As automation relieves drivers from various driving tasks including vehicle control (e.g. steering, accelerating, and braking), driving performance measures (e.g. speed, lane deviations) may not be informative indicators for evaluating the effectiveness of in-vehicle displays. Gaze-based measures are a better alternative given their link to driver visual attention, an indication of driver engagement. A scoping review was conducted to review the literature on the design of displays for supporting the operation of driving automation and the evaluation of these displays using gaze-based measures. Forty-three articles were included in the review. Most of the studies investigated visual (and mixed visual-auditory) displays that provide alerts to the driver for when to intervene automation classified as Level 3. The adopted gaze measures mostly relied on static areas of interest (AOIs), with fewer studies looking at more fine-grained, context dependent AOIs. The paper summarises the findings of the review, including research trends and gaps, as well as recommendations for future research. [ABSTRACT FROM AUTHOR]

Vehicle hydraulic braking systems are widely used, structurally complex. Reliability allocation during the design phase is crucial, yet there is a relatively limited body of research on this subject. In response, a new method for vehicle hydraulic braking system is proposed: the comprehensive reliability allocation method based on partial fuzzy ratings and considering failure correlation (CRA-PFRAFC). Based on the analysis of reliability allocation criteria impacting the braking system, the fuzzy set theory is introduced into the comprehensive allocation method, and the criteria with strong subjective dependence are fuzzy evaluated. The braking system allocation model is established by Gumbel Copula function. According to the set reliability target, the model is solved to allocate the failure rates to each subsystem according to the allocation vector. An example illustrates the advantages of this method. The results show that the reliability of the brake assembly is the lowest, while the reliability of the vacuum booster system is the highest. By fuzzy rating the failure severity and failure occurrence, the subjective quantification problem in traditional method is avoided. Meanwhile, compared with the traditional subsystem independent assumption model, this method is more realistic, and the failure rate of subsystem allocation is increased by 20% on average. Therefore, this study provides necessary and effective theoretical basis for reducing the design and manufacturing costs of vehicle hydraulic braking systems. [ABSTRACT FROM AUTHOR]

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control 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.)

We propose an inhibitory control system for downhill turning by using a pre-installed friction brake mounted on a manual wheelchair. The braking force of the wheel is controlled by an added DC geared motor that pulls the brake wire in accordance with the ground angle. The proposed automatic braking system can reduce unexpected turns on downhill slopes. The proposed control system is also designed to be installed as an add-on device for manual wheelchairs. The effectiveness of the proposed system is verified using a wheelchair through a slope running experiments. [ABSTRACT FROM AUTHOR]

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.)

This study presents an energy regeneration model and some theory required to construct a regeneration braking system. Due to the effects of carbon dioxide (CO2) emissions, there is increasing interest in the use of electric vehicles (EVs), electric bikes, electric bicycles, electric buses and electric aircraft globally. In order to promote the use of electric transportation systems, there is a need to underscore the impact of net zero emissions. The development of EVs requires regenerating braking system. This study presents the advantages of regenerative braking. This system is globally seen in applications such as electric cars, trams, and trains. In this study, the design specification, design methodology, testing configurations, Simulink model, and recommendations will be outlined. A unique element of this work is the practical experiment that was carried out using 1.5 Amps with no load and 2.15 Amps with a load. The discharge voltage was purely from the 22 W bulb load connected to the capacitor bank as we limited this study to the use of 1.5 Amps and it took 15 min for a full discharge cycle, after which no charge was left in the capacitor bank. The results showed that the discharge rate and charging rate for the regenerative braking system were effective but could be improved. The objective of this paper is to investigate how a supercapacitor works alongside a battery in regenerative braking applications. This study demonstrates that the superconductor used can deliver maximum power when required. Also, it can also withstand elevated peaks in charging or discharging current via the supercapacitor. Combining a battery with a supercapacitor reduces the abrupt load on the battery by shifting it to the capacitor. When these two combinations are used in tandem, the battery pack's endurance and lifespan are both boosted. [ABSTRACT FROM AUTHOR]

Copyright of Automobile Technology is the property of Automobile Technology 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.)

Purpose. Study of hydraulic-mechanical transmissions in the process of braking a mining diesel locomotive and determining their efficiency. Methodology. The paper uses the technique of matrix analysis of transmissions by Prof. V.B. Samorodov, based on the division of the kinematic scheme into structural elements. The method was chosen as the basic method due to its universality and the possibility of implementation with the help of computer technology. The developed mathematical models of the vehicle braking process take into account the possibility of a smooth change (decrease and increase) of the transmission ratio and the torque applied to the executive bodies. Findings. The advantages and disadvantages of the use of hydromechanical step-less transmissions in the braking modes of the diesel locomotive are determined. It was mathematically proven that such transmissions are efficient, it is limited by methods of implementing braking. The results of the modelling allow to justify the braking control strategies of the locomotive equipped with a hydromechanical transmission. Originality. The technique of matrix mathematical modelling of transmissions that work as part of mining and transport machines has got further development. The developed mathematical model of the braking process of a mine diesel locomotive with HMT allowed to study the change in the kinematic and power parameters of the transmission in different operating conditions of diesel locomotives – movement on traction and transport ranges, on descent and ascent, at different initial braking speeds for all possible ways of implementing the process braking. The obtained results made it possible to substantiate the braking control strategies depending on the initial speed and traction power of the mining diesel locomotive. Practical value. The obtained results testify to the operational efficiency of the considered transmissions due to correctly selected strategies of braking control, which exclude the possibility of the occurrence of emergency modes of operation, failure, and reduction of the service life of the transmission elements. The practical value of the paper is confirmed by the social effect due to the improvement of labour safety in locomotive transport. [ABSTRACT FROM AUTHOR]