Browse Topic: Brake-by-wire

Items (124)
Find
A Study on TSC(Technical Safety Concept) design and verification in EMB(Brake By Wire) Systems2026-01-0095To be published on 04/07/2026
The Electro-Mechanical Brake (EMB) system, a dry-type Brake-by-Wire technology, represents a significant advancement in eco-friendly and intelligent vehicle braking systems. Unlike conventional hydraulic brakes, EMB eliminates fluid-based components by directly controlling friction braking through electrical actuators installed at each wheel. This not only reduces environmental impact but also enhances system responsiveness and integration with advanced driver assistance systems (ADAS). The EMB architecture comprises six controllers: a Main Center Control Unit, a Backup Center Control Unit for redundancy, and four Wheel Control Units. These controllers communicate seamlessly using multiple vehicle communication protocols, including CAN, Ethernet, and FlexRay. This distributed control structure is essential for achieving compliance with ISO 26262, the international standard for functional safety in road vehicles. As EMB systems become more complex, they introduce new safety risks that
KIM, Dokun
Research on Vehicle and Longitudinal Tire Model Parameters Identification Based on Electro-Mechanical Brake System2026-01-0634To be published on 04/07/2026
The Electro-Mechanical Brake (EMB) system is a novel type of brake by wire systems with independently controllable characteristics. This system aids in the decoupling analysis of the vehicle and actuator dynamics, thereby improving the accuracy of parameter identification. Therefore, this paper proposes an innovative parameter identification method for vehicle parameters and longitudinal tire model parameters, based on the characteristics of the EMB system and onboard sensors. First, based on the wind resistance and rolling resistance coefficients obtained from the vehicle coasting conditions, a decoupled constant clamping force sequence braking condition for the front and rear axles is designed by integrating the characteristics of the EMB actuator and vehicle dynamics. This approach enables the identification of vehicle and nonlinear longitudinal tire model parameters, significantly improving the accuracy of parameter identification. Next, considering the nonlinear characteristics of
Huang, Jiayi, Cheng, Yulin, Zhuo, Guirong, Le, Qiao, Wei, Wei, Shu, Qiang
Modular 3-D Lumped Parameter Thermal Network for Thermal Estimation of Permanent Magnet Synchronous Motors in Electro-Mechanical Braking Systems2026-01-0136To be published on 04/07/2026
With the development of electric intelligent vehicles, drive-by-wire systems are gradually popularized, the thermal reliability of electro-mechanical brake (EMB) motors, as the key actuators of drive-by-wire systems, is closely related to vehicle safety. However, the blocked-rotation operating condition of EMB motors typically involves applying unequal DC currents to the three-phase windings to achieve braking. This results in uneven winding heating, and conventional thermal models may fail to accurately represent the heat transfer dynamics arising from such tangential thermal imbalance, creating risks of motor local overheating. This paper is focused on thermal performance analysis of EMB motors under blocked-run conditions. First, a single-tooth lumped-parameter thermal network module (tooth module) incorporating external interfaces was developed. This module was adapted using experimental and simulation data, with its internal thermal parameters identified via a particle swarm
duan, yanlong, Xiong, Lu, Wang, Xinjian, Zhuo, Guirong, Zeng, Jie
Active Thermal Management of EMB Motors Considering Winding Heat Imbalance2025-01-733112/31/2025
The electro-mechanical brake (EMB) system represents a novel dry brake-by-wire technology renowned for their superior control performance and compact structure, effectively meeting the demands of intelligent electric vehicles. However, its performance can be compromised under extreme ambient temperatures and non-uniform heat generation across the coils. This study addresses the critical challenge of single-phase overheating in the EMB motor actuator during low-speed high-torque operations by proposing a novel Maximum Duration Per Torque (MDPT) control strategy. The core of this method is to optimize the allocation of dq-axis currents. It aims to extend the safe operating duration of the EMB while respecting its thermal constraints and maintaining full braking performance. Firstly, based on the operational characteristics of the EMB, we establish a lumped parameter thermal network (LPTN) model. This model accurately captures the uneven thermal distribution among the three-phase windings
Zeng, Jie, Xiong, Lu, Zhuo, Guirong, Duan, Yanlong, Wang, Xinjian
Research on Wheel Slip Ratio Control for Electro-Mechanical Brake System: From PI to High-Order Sliding Mode Control2025-01-733212/31/2025
The electro-mechanical brake (EMB) system is a novel dry-type brake-by-wire system that features superior control performance and a compact structural design, effectively meeting the development demands of intelligent and electrified vehicles. However, current research on anti-lock braking system (ABS) primarily focuses on hydraulic brake system and mostly remains at the simulation and hardware-in-the-loop testing stages. Therefore, this paper validates the feasibility of slip ratio control based on EMB actuators through both simulation and real-vehicle experiments. First, this paper establishes an equivalent second-order response model for the closed-loop EMB control system through theoretical derivation and identifies the dynamic response characteristics of the EMB actuator via sinusoidal frequency sweep testing. Next, it compares two control strategies: one that uses the reference slip ratio as the direct control target, and another that uses reference wheel speed as the direct
Cheng, Yulin, Qiao, Le, Wang, Chenyu, Li, Congcong, Zhuo, Guirong, Wei, Wei
A Unified Layer-by-Layer Progressive Framework for Sensorless Control of Brake-By-Wire Systems2025-01-732812/31/2025
Conventional control of Brake-by-Wire (BBW) systems, including electro-hydraulic brake(EHB) and electro-mechanical brake(EMB), relys on pressure sensors, the errors of which usually resulted inaccurate braking force tracking bringing a lot of safety hazards, e.g., wheel locking and slipping. To address challenges of accurate braking force control under the circumstance of the system nonliearities (such as friction) and uncertainties (such as stiffness characteristics) for a sensorless BBW system, this paper proposes a unified Layer-by-Layer Progressive (LLP) control framework to enable fast and precise brake control. The work has been conducted with three new contributions in the three cascaded stages within the control framework: in the coarse compensation stage, a load-adaptive LuGre friction model is proposed to handle modellable nonlinearities; in the fine compensation stage, an Adaptive Extended Disturbance Observer (AEDO) is developed to estimate and compensate for parameter
Zhou, Quan, Lv, Zongyu, Han, Wei, Li, Congcong, Zhao, Xinyu, Xiong, Lu, Shu, Qiang
Enhancing Robustness of Electro-Hydraulic Brake-by-Wire Actuators via Linear Active Disturbance Rejection Control2025-01-03419/15/2025
In recent years, motorsport has increasingly focused on environmental concerns, leading to the rise of hybrid and fully electric competitions. In this scenario, electric motors and batteries take a crucial role in reducing the environmental impact by recovering energy during braking. However, due to inherent limitations, motors and battery cannot fully capture all braking power, necessitating the use of standard friction brakes. To achieve an efficient balance between electric motors and friction brakes, the brake pressure can no longer be directly controlled by the driver. Instead, it must be computed by the Vehicle Control Unit (VCU) and sent to a smart actuator, i.e. the Brake-By-Wire (BBW), which ensures that the required pressure is applied. The standard approach to achieve precise pressure control is to design a nested Proportional-Integral-Derivative (PID) control architecture, which requires an accurate nominal model of the system dynamics to meet the desired tracking
Gimondi, Alex, Dubbini, Alberto, Riva, Giorgio, Cantoni, Carlo
Applying Specialized System Analysis for Brake by Wire in Software Defined Vehicles: The Development of a System Analysis Tool (SAT)2025-01-03559/15/2025
The emergence of Software Defined Vehicles (SDVs) has introduced significant complexity in automotive system design, particularly for safety-critical domains such as braking. A key principle of SDV architecture is the centralization of control software, decoupled from sensing and actuation. When applied to Brake-by-Wire (BbW) systems, this leads to decentralized brake actuation that demands precise coordination across numerous distributed electronic components. The absence of mechanical backup in BbW systems further necessitates fail-operational redundancy, increasing system complexity and placing greater emphasis on rigorous system-level design validation. A comprehensive understanding of component interdependencies, failure propagation, and redundancy effectiveness is essential for optimizing such systems. This paper presents a custom-built System Analysis Tool (SAT), along with a specialized methodology tailored for modeling and analyzing BbW architectures in the context of SDVs
Heil, Edward, Zuzga, Sean, Babul, Caitlin
Active Online Estimation of the Electromechanical Brake Coulomb Friction2025-01-03429/15/2025
Electro-mechanical braking (EMB) system has emerged as a potential candidate that serves the brake-by-wire technology. Several mechanisms are used to transmit the clamp force, where each has efficiency losses due to static friction and viscous damping. Compensating these losses is essential for accurate responses such that meeting the performance goal and improving the stopping distance of the EMB. Mathematical and empirical models are used to estimate these losses so that clamp force is accurately estimated and controlled. However, none of these models are capable of addressing the part-to-part variation or predicting the impact of other noise factors on these losses such as operating temperature and degradation. The purpose of this work is to online estimate the EMB coulomb friction by introducing an external torque command over a period of time while observing the system’s response. This approach continuously measures the coulomb friction while the system is in normal operation
Aljoaba, Sharif, Ramakrishnan, Raja, Dobbs, Jeremy
Actuator-to-Vehicle Joint Estimation of Clamping Force for Sensorless Control of the Electro-Mechanical Brake System2025-01-03389/15/2025
The electro-mechanical brake (EMB) is a promising brake actuating system for electrified vehicle. To enhance the system function safety while saving space from redundancy sensors, this paper studied sensorless climbing force control for the EMB where a new climbing force estimator is proposed by fusing the information from vehicle dynamics and EMB states. The work was done with three contributions: 1) The priori clamping force characteristics were implemented to build the estimator with two parallel models, one of which was derived from the actuator rigid-body dynamics while the other was derived from vehicle longitudinal dynamics model; 2) a proportional-integral (PI) observer utilizing wheel speed residual signals was developed to correct the initial estimates iteratively; 3) a fuzzy control controller was proposed to optimize the key parameters of the PI observer. Comparative study was conducted on a co-simulation platform and the results showed that the actuator-to-vehicle joint
Xing, Yipu, Zhou, Quan, Cheng, Yulin, Li, Congcong, Han, Wei, Zhuo, Guirong, Xiong, Lu
Longitudinal Dynamic Metrics for Describing and Developing the Deceleration Behavior of Vehicles in the Concept Phase2025-01-02647/2/2025
The brake system is a critical safety component in motor vehicles. Advances in the electrification of the powertrain and the rise of autonomous driving technologies are significantly impacting the brake system, which allows innovative approaches and necessitating the development of new brake concepts and new deceleration strategies. A major technological advance is the decoupling of the driver from the brake system through Brake-by-wire technology. A crucial attribute of Brake-by-wire systems is the attainment of a concept-independent deceleration behavior. To establish a consistent and brand-specific deceleration behavior in the early development phase, objective metrics and perceptual thresholds are required to describe the desired subjective braking behavior. Moreover, objective metrics are indispensable for the virtual phase of the vehicle development process. This article focuses on deceleration from a straight-ahead drive. To identify objective metrics and perceptual thresholds
Biller, Ralph, Udovicic, Matej, Ketzmerick, Erik, Kirch, Sebastian, Mayr, Stefan, Prokop, Günther, Wagner, Andreas
Braking Force Distribution Strategy for Brake-by-Wire Systems: Enhancing Safety and Redundancy10-09-03-00286/9/2025
Brake-by-wire (BBW) systems, characterized by fast response, high precision, ease installation, and simplified maintenance, are highly likely to become the future braking systems. However, the reliability of BBW is currently inferior to that of traditional hydraulic braking systems. Considering ECE R13 regulations, actuator reliability, and braking efficiency, this article first proposes a new braking force distribution strategy to prevent braking failure and enhance vehicle safety without modifying the actuator itself. The strategy reduces the operating frequency of rear actuators during low- and medium-intensity braking, thereby extending their service life and operational reliability. Then, the co-simulation model combining Simulink and AMESim was established for simulation validation based on direct drive braking actuator. Additionally, the real-vehicle test platform was built for typical braking scenarios. The simulation and experimental results show that this strategy
Li, Tianle, Gong, Xiaoxiang, He, Chunrong, Deng, Zhenghua, Zhang, Hong, Xu, Rong, He, Haitao, Wang, Xun, Zhang, Huaiyue
Letter from the Guest Editors10-09-02-00095/19/2025
Letter from the Guest Editors
Wang, Zhenfeng, Zhang, Yunqing, Qi, Ronghuai, Lu, Yukun
Development of an Imperceptible Brake Failure Control Technology and Real Vehicle Application10-09-02-00154/26/2025
With the advancement of control technology in the automotive field, there is a possibility of cross-system redundant control between various actuators. As for the braking system, current brake-by-wire system often uses mechanical backup braking methods to give the vehicle a certain braking capacity after failure. However, in the mechanical backup braking mode, the brake master cylinder is connected to the supporting wheel cylinder, and the brake assist is lost, which leads to an increase in brake pressure and makes it difficult for the driver to step on the brake pedal. Meanwhile, due to the limitation of the brake master cylinder stroke, the maximum braking deceleration of the vehicle is only 3 m/s2 after the driver fully presses the brake pedal. The above two defects greatly affect the safety of the vehicle during backup braking. To solve the above problems, this article takes electric vehicles as the research object, designs a new type of hydraulic circuit for the braking system
Tian, Boshi, Li, Liang, Liao, Yinsheng, Lv, Haijun, Hu, Zhiming, Sun, Yue, Qu, Wenying
A Control and Fault-Tolerant Strategy Based on Electromechanical Brake System2025-01-82654/1/2025
With the development of automotive electrification and intelligent technology, vehicles have higher and higher requirements for braking systems. On the one hand, it requires it to have an active braking function, and at the same time facilitates the integration with other control systems of the chassis domain. The system should minimize oil pollution as much as possible, and under the premise of ensuring the pedal force, it can be used to recover the brake energy as much as possible to improve the range of electric vehicles as possible. The new brake system based on Electronic mechanical brake (EMB) as a line -controlled decoupling braking system can not only meet the needs of the brake pedal sensation, but also achieve continuous and accurate control of braking power. It can effectively Taking into account braking economy, braking safety, and braking comfort. In addition, the development of EMB technology is still immature and the failure rate is high, so research on EMB's fault
Li, Xuesong, Qin, Keyun, Zheng, Hongyu, Kaku, Chuyo
A Nonlinear Characteristics Identification and Compensation Control Method for Electromechanical Brake System2025-01-88104/1/2025
Clamping force control in Electromechanical Brake (EMB) systems must overcome various nonlinear characteristics, such as motor distorted voltage, Back Electromotive Force (EMF), and actuator friction disturbances. Therefore, modeling and parameter identification of these nonlinearities are necessary. This paper first proposes a motor parameter identification method based on the mathematical model of a Permanent Magnet Synchronous Motor (PMSM). A combination of the Least Square Method and Particle Swarm Optimization (PSO) is used to stepwise identify both the electrical and mechanical parameters of the motor. The accuracy of the identified parameters is validated by comparing simulation results with test bench responses. The identified parameters are applied to design the motor Back EMF compensation module, the distorted voltage compensation module, and to tune the current loop parameters. Next, a lumped parameter friction model suitable for closed-loop clamping force control in EMB
Qiao, Le, Xiong, Lu, Zhuo, Guirong, Shu, Qiang
Research on Composite Braking Strategy of Pure Electric Commercial Vehicle on Downhill Low-Adhesion Road Considering Rainfall Intensity2025-01-88134/1/2025
As a distributed wire control brake system, the electro-mechanical brake (EMB) may face challenges due to the need to integrate the actuator in the limited space beside the wheel. During extended downhill braking, especially on wet roads with reduced adhesion, the EMB must operate at high intensity. The significant heat generated by friction can lead to thermal deformation of components, such as the lead screw, compromising braking stability. This paper focuses on pure electric light trucks and proposes a tandem composite braking method. This approach uses an eddy current retarder (ECR) or motor to provide basic braking torque, while the EMB supplies the dynamic portion of the braking torque, thereby alleviating the braking pressure on the EMB. First, a driver model, tire model, motor model, and braking models are developed based on the vehicle's longitudinal dynamics. In addition, the impact of various factors, such as rainfall intensity, road slope, ramp length and vehicle speed, on
Liu, Wang, Zhang, Yu, Xiao, Hongbiao, Shen, Leiming
Concept of an Electromechanical Brake-By-Wire System for Battery-Electric Vehicles2025-01-88044/1/2025
Brake-by-wire systems have received more and more attention in the recent years, but a close look on the available systems shows, that they have not reached full by-wire level yet. Most systems are still using hydraulic connections between main cylinder and the brake calipers on at least one axle to ensure functional safety. Mostly, this is the front axle, since the front brakes have to convert more kinetic energy during braking manoeuvers. Electromechanical actuators are currently used for rear brakes in hybrid brake-by-wire applications solely, since a loss of the front brake calipers can lead to severe conditions and control loss of the vehicle during braking. Further, the higher mass of battery electric vehicles (BEVs) leads to much higher braking forces on both axles and to increased sizes of the electromechanical calipers. This article presents a concept for a brake-by-wire system for battery electric vehicles, which features electromechanical brake actuators on all corners and a
Heydrich, Marius, Lenz, Matthias, Ivanov, Valentin, Stoev, Julian, Lecoutere, Johan
Modeling and Analysis of Comfort Braking Control Based on Brake-by-Wire and Active Suspension Systems10-09-02-00112/7/2025
As wire control systems advance, they have given rise to a diverse suite of advanced driver assistance services and sophisticated fusion control capabilities. This article presents an innovative strategy for achieving comfortable braking in electric vehicles, propelled by the unwavering goal of enhancing driving experience. By integrating active suspension systems with brake-by-wire technology, the approach ensures that drivers retain their confidence throughout the braking process. The brake-by-wire system adeptly discerns the driver’s braking intent through the pedal’s displacement sensor. Utilizing this technology, we have developed a pioneering function aimed at delivering comfort braking control (CBC). This function not only refines the braking experience but also solidifies the driver’s trust in the braking system. Designed to counteract the head nodding effect during vehicle deceleration, the CBC system minimizes or even eradicates the jarring sensation of pitching for both the
Tian, Boshi, Li, Liang, Liao, Yinsheng, Lv, Haijun, Qu, Wenying, Hu, Zhiming, Sun, Yue
Feedforward Control of Clamping Force in Electronic Mechanical Brake System Based on Inertia Identification and Load Torque Observation2025-01-70511/31/2025
The braking system is an essential element for ensuring the safe operation of vehicles. This research investigates the influence of electronic mechanical brakes on the control performance of permanent magnet synchronous motors, with a particular focus on variations in the load torque and inertial load. This study addresses challenges such as delayed responses in the clamping force and diminished control accuracy. To mitigate these issues, a Luenberger load torque observer is utilized for the real-time identification of load torque. The identified load torque is subsequently converted into a compensation current, which is integrated into the current loop as a feed-forward compensation signal to enhance the control performance. Additionally, to reduce the impact of variations in inertial load on the overall control system, this study employs a model reference adaptive algorithm for the online identification of rotational inertia, with the identification results being fed back to the load
Wan, Xiaobo, Shang, Ruipeng, Li, Yingchun
Modeling and Simulation of an Electromagnetic Brake-by-Wire System for Formula SAE Vehicles2024-36-016912/20/2024
Electric vehicles represent a shift towards sustainability in the automotive industry, with the Brake-by-Wire (BBW) system as an innovation to enhance safety, and performance. This study proposes an electromagnetic BBW system for Formula SAE vehicles, optimizing an electromagnet with a genetic algorithm as the actuator. Through a selection process from a million individuals, the system was modeled. Integrated with electric motors using CarMaker® software, the optimized electromagnet surpassed the minimum required force of 228.08 N without reaching its nominal current of 12.5 A, achieving a force of 231.1 N for 150 W power, indicating an energy efficiency of 0.706 N/Watt. The system also exhibited a response time of 17.92ms for an 80 bar increase, 1.52 times better than compared systems. Simulation under varying braking intensities demonstrated dynamic behavior, with settling times for slow, moderate, and sharp braking at 193 ms, 62 ms, and 21 ms, respectively. Efficiency during
Salgado, Vinícius Batista Alves, Gomes, Deilton Gonçalves, Andrade Lima, Cláudio
Research on Direct-Drive Brake Actuator and Its Control Method for Electric Vehicles10-09-01-000311/8/2024
With the rapid development of electric vehicles, the need for improved reliability and safety performance of electric vehicle braking systems has become paramount. In response to this demand, a novel direct-drive brake-by-wire actuator based on linear motors was designed to address these challenges. This article presents the structure and principles of the proposed braking actuator. Leveraging the traditional electromechanical brake systems as a foundation, the prototype was modified and fabricated. Additionally, the control and drive system for the braking actuator was established using the TMS320F28335 digital signal processor. Moreover, the current-position dual closed-loop control algorithm was devised to regulate the braking force accurately. Experimental results demonstrate that the direct-drive brake-by-wire actuator exhibits rapid responsiveness and precise braking force modulation, showcasing promising prospects in the field of electric vehicle braking.
He, Haitao, He, Chunrong, Gong, Xiaoxiang, Deng, Zhenghua, Li, Tianle, Wang, Xun, Zhang, Hong, Xu, Rong
Safety Concepts for Future Electromechanical Brake Central Control Systems15-18-01-000410/25/2024
Electromechanical brakes (EMB) are currently coming into focus in the automotive industry. This trend was confirmed in 2022, when a first automotive supplier [1] announced the series production of EMB systems. One major driver is safety, especially if EMB systems are implemented with smart actuators that install redundant electronic control units (ECU) and distributed software [1]. Earlier, the authors have addressed safety mechanisms in EMB actuators [2]. In this article the authors extend their investigation to address safety mechanisms in future EMB central control systems (CCS). Impact of different brake system topologies (X-, H-, centralized) vis-à-vis potential safety mechanisms within communication buses and ECUs is analyzed.
Schrade, Simon, Röhler, Andreas, Nowak, Xi, Verhagen, Armin, Schramm, Dieter
Understanding the Actuation Point Stiffness of Electromechanical Drum Brakes15-18-01-00029/24/2024
Electromechanically actuated drum brakes are one interesting option for the realization of brake-by-wire systems for future electric vehicles. A key characteristic for the design and control of electromechanical brake actuators is the actuation point stiffness, as this quantity relates the actuation force to the required actuator position. The various known approaches for the control of electromechanical brakes, which primarily focus on disc foundation brakes, typically rely on the stiffness curve at least to some extent. A transfer of these approaches to drum brakes is not straightforward, because the actuation point stiffness for drum brakes is much more complex compared to disc brakes. In particular, a strong hysteretic behavior is observed for the standing drum and a considerable change of the stiffness and hysteresis can be observed for the rotating drum. Although drum brakes have been used for decades these effects have not been thoroughly discussed in literature, yet. Hence
Peter, Simon, Janhsen, Michael, Stümke, Daniel, Görges, Daniel
Design, Modeling, and Control of Electronic Mechanical Brake System: A Review10-08-04-00268/28/2024
The electronic mechanical brake (EMB) system is a critical actuator for achieving brake-by-wire control. This review categorizes and summarizes the literature related to EMB into three sections: actuator, mathematical modeling, and control strategies. In the actuator aspect, this article compares and analyzes motors, motion conversion mechanisms, and self-reinforcing mechanisms. For mathematical modeling, this article reviews modeling methods for EMB systems concerning motors, transmission mechanisms, friction, contact collisions, nonlinear stiffness, and hysteresis characteristics. Regarding control strategies, this article consolidates methods for clamp force control, clamp force estimation, and gap management. Finally, the article discusses potential future research directions in EMB from both hardware structure and software algorithm perspectives.
Yan, Zhoudong, Peng, Hang, Chen, Xinbo, Yan, Min
Information on Brake-By-Wire (BBW) Brake Control SystemsAIR5372A (Current)5/14/2024
This SAE Aerospace Information Report (AIR) describes the design approaches used for current applications of aircraft Brake-by-Wire (BBW) control systems. The document also discusses the experience gained during service, and covers system, ergonomic, hardware, and development aspects. The document includes the lessons that have been learned during application of the technology. Although there are a variety of approaches that have been used in the design of BBW systems, the main focus of this document is on the current state of the art systems.
A-5A Wheels, Brakes and Skid Controls Committee
Gap Adjustment Strategy for Electromechanical Brake System Based on Critical Point Identification2024-01-23204/9/2024
Abrasion of the Electromechanical brake (EMB) brake pad during the braking process leads to an increase in brake gap, which adversely affects braking performance. Therefore, it is imperative to promptly detect brake pad abrasion and adjust the brake gap accordingly. However, the addition of extra gap adjustment or sensor detection devices will bring extra size and cost to the brake system. In this study, we propose an innovative EMB gap active adjustment strategy by employing modeling and analysis of the braking process. This strategy involves identifying the contact and separation points of the braking process based on the differential current signal. Theoretical analysis and simulation results demonstrate that this gap adjustment strategy can effectively regulate the brake gap, mitigate the adverse effects of brake disk abrasion, and notably reduce the response time of the braking force output. Monitoring is critical to accurately control EMB clamping force. Pressure transducers are
Zhang, Yilong, Chen, Zixuan, Wu, Jinglai, Zhang, Yunqing
Safety Concepts for Future Electromechanical Brake Actuators15-17-03-00122/16/2024
A growing interest in electromechanical brakes (EMB) is discernible in the automotive industry finding its climax in an announcement of EMB series production in late 2022 [1]. The introduction of EMB allows for new design opportunities using distributed software on smart actuators. However, additional efforts are needed to ensure continuously high levels of safety even when established design principles in the brake system are changed. This article discusses different safety concepts that could potentially be put in place in EMB actuators. Therefore, safety goals that need to be satisfied by an actuator are derived. Furthermore, three different degrees of complexity are differentiated, evolving to different required electronic control units (ECU) and architectures. Additionally, also the safety of the actuation unit (AU) is considered to realize a holistic safety concept for the actuator. Finally, a conclusion is drawn comparing the different investigated concepts.
Schrade, Simon, Röhler, Andreas, Nowak, Xi, Verhagen, Armin, Schramm, Dieter
A Renewed Look at Centralized vs. Decentralized Actuation for Braking Systems2023-01-186511/5/2023
De-centralized brake actuation – that is, brake systems that incorporate individual actuators at each wheel brake location to both provide the apply energy and the modulation of braking force – is not a new area of study. Typically realized in the form of electro-mechanical brake calipers or drum brakes, or as “single corner” hydraulic actuators, de-centralized actuation in braking systems has already been deployed in production on General Motor EV1 Electric Vehicle (1997) in the form of electric drum brakes and has been studied continually by the automotive industry since then. It is frequently confused with “brake by wire,” and indeed practical implementations of de-centralized actuation are a form of brake by wire technology. However, with millions of vehicles on the road already with “brake by wire” systems - the vast majority of which have centralized brake actuation – the future of “brake by wire” is arguable settled. The question of what is next for braking technology is
Antanaitis, David
Applying Ferritic Nitrocarburizing (FNC) in Conjunction with Smart ONC® on GCI Brake Rotors: The New Generation of FNC Rotors to Meet the Euro 7 Standards2023-01-188811/5/2023
As the regulations aiming to limit air pollution become stricter, the battle against non-exhaust emissions known to be harmful to human health and the environment is attracting more focus and extending worldwide. EVs are equipped with a hybrid braking system combining regenerative and hydraulic braking to provide the same performance as traditional vehicles. Whenever the regenerative braking torque is insufficient to give the necessary deceleration rate, the hydraulic and electromechanical braking torque is applied. Thus, the recuperative braking of EVs reduces the need for brakes. As the brakes are not used as often, dust and rust will accumulate and impede their performance, so brake problems can arise from not using them enough. Due to the extra weight of EVs compared to ICEVs, more particulates are released through increased corrosion and friction on the braking system. Grey cast iron brake rotors rust quickly, and excessive corrosion causes heavy damage to the rotor’s surface
Nousir, Saadia, Winter, Karl-Michael
Electro-Hydraulic Composite Braking Control Optimization for Front-Wheel-Driven Electric Vehicles Equipped with Integrated Electro-Hydraulic Braking System2023-01-186411/5/2023
With the development of brake-by-wire technology, electro-hydraulic composite braking technology came into being. This technology distributes the total braking force demand into motor regenerative braking force and hydraulic braking force, and can achieve a high energy recovery rate. The existing composite braking control belongs to single-channel control, i.e., the four wheel braking pressures are always the same, so the hydraulic braking force distribution relationship of the front and rear wheels does not change. For single-axle-driven electric vehicles, the additional regenerative braking force on the driven wheels will destroy the original braking force distribution relationship, resulting in reduced braking efficiency of the driven wheels, which are much easier to lock under poor road adhesion conditions. The integrated Electro-Hydraulic Braking system (iEHB) is the current advanced brake-by-wire system, which can build brake hydraulic pressure by its motor, and independently
Zhao, Xinyu, Xiong, Lu, Zhuo, Guirong, Shu, Qiang, Zhao, Xuanbai
Brake-by-Wire System Redundancy Concept for the Double Point of Failure Scenario10-07-03-00216/22/2023
Brake-by-wire (BbW) systems are one key technology in modern vehicles. Due to their great potential in the areas of energy efficiency and automated driving, they receive more and more attention nowadays. However, increased complexity and reliance on electric and electrical components in BbW systems bring about new challenges. This applies in particular to the fault tolerance of the brake system. Since drivers cannot form a fallback layer of braking functions due to the mechanical decoupling of the brake pedal, known BbW concepts provide a redundant system layer. However, driving is significantly limited in the event of a failure in the BbW system and is only possible under certain restrictions. The reason for that is a further possible failure (double point of failure scenario), which can result in a significant loss of braking performance. To improve the availability level of the braking functions, a principally new redundancy concept for the double point of failure scenario is
Schlimme, Hauke Christian, Henze, Roman
Dodge is ready to sting the compact-SUV market23AUTD05_145/1/2023
If you accept that the oddball and odd-sized Journey never was a legit rival for the likes of the Honda CR-V, Toyota RAV4 and Ford Escape - and it wasn't - Stellantis' Dodge brand hasn't played in the compact SUV segment, one of the largest and most competitive in the U.S. That strategic gap is set to be filled by the 2023 Hornet, Dodge's performance-slanted attempt to peel out some sales volume from among the C-segment utilities that are typified by mundane and softly-tuned top-sellers. The Hornet's not just about having a little more engine power, either. Its platform is shared with the Alfa Romeo Tonale. Like Hornet, the Tonale slated to be in showrooms sometime in spring 2023 and incorporates chassis finery such as standard Koni-supplied Frequency Selective Damping (FSD) dampers. Specifically tuned, genuine by-wire braking (for the R/T trim) reduces curb weight by 9 lb. (4 kg) and improves steering feel via direct-action ratios from the electronic power steering; Stellantis claimed
Visnic, Bill
Methodologic Assessment of Brake-by-Wire System Modelling with Regard to Accuracy, Model Complexity and Optimization Efforts2023-01-06664/11/2023
Brake-by-wire systems are an innovative and important component of modern high-performance and also electrified vehicles. Due to their decoupled architecture, they enable driver-independent vehicle dynamics control (e.g., brake torque blending) and easy integration of assistance functionalities (e.g. Emergency Brake Assist (EBA)). On the other hand, the development of these functions can cause high costs and development effort, and testing can be critical in case of improper gain tuning. Therefore, already in the concept phase, a large part of the testing is shifted to virtual environments and simulations that allow safe and reproducible experiments without damage. Therefore, suitable and reliable models are needed to represent reality as accurately as possible. This paper deals with the modelling of a purely electrohydraulic brake-by-wire system and a hybrid system with electrohydraulic brakes on the front axle and electromechanical brakes on the rear axle. For comparison, both an
Heydrich, Marius, Kellner, Björn, Ivanov, Valentin
Panel Discussion: Advanced Brake Engineering for Future Vehicle Architectures1335310/13/2022
This panel will address two topics of interest related to the design, development, supplier-OEM relationship and customer experience for braking systems; the issues and challenges to implement braking systems in autonomous vehicles and the future implementation of dry brake by wire brake systems will be discussed. Experts from two major OEMs, two Tier 1 suppliers and from a Systems Engineering Integrator will bring their perspectives and input on these topics. Although either topic could be a conference in itself, the primary issues and challenges facing the industry as these technology areas approach reality will be addressed. Moderator: Jay Fash, Zoox Panelists: Robert Hill, Mando America Corporation John Pennala, General Motors LLC Beniamin Szewczyk, Brembo Spa Bernat Ferrer, Applus Idiada USA Hal Felch, Ford Motor Company
Schandelmeier, Brandie
Research on Brake Comfort Based on Brake-by-Wire System Control2022-01-09123/29/2022
The vehicle will produce certain shock and vibration during the braking process, which will affect the driving experience of the driver. Aiming at the problems of pitch vibration, longitudinal vibration and shock during the braking process, this paper proposes a planning and following control method for target longitudinal acceleration in post-braking phase, and designs control trigger strategies. Target longitudinal acceleration planning takes minimizing longitudinal shock as the design goal. The following control takes the brake pressure as the control object, and adopts the “feedforward +PID feedback” method to follow the target longitudinal acceleration. Besides, considering the safety of braking process, the trigger condition of control is designed which utilizes BP neural network method to judge whether the control has to be triggered. Based on Simulink software, the simulation model of straight-line braking is established. The results of straight-line braking simulation show
Xiong, Wei, Wang, Weiwei, Jiang, Kaihong, Hou, Liming, Shangguan, Wen-Bin
Design and Hardware in the Loop Testing of AEB Controllers2022-01-00993/29/2022
Current ADAS systems can improve vehicle safety directly influencing its dynamics, reducing the impact of human error while driving. These functionalities have a high impact on the complexity of each unit installed on the car, potentially increasing the development time. In this work, a Hardware in the Loop testing bench and methodology for Autonomous Emergency Braking system is presented, aiming to enable a faster system development process. A commercial production brake by wire unit has been installed on a real-time driving simulator. The AEB functionality of the unit is activable in real-time during the simulation, by the means of a customizable control strategy. Two different AEB controllers have been implemented: the first one reproduces the unit stock functionality, while the second computes the requested deceleration using a PID control strategy. The two controllers have been tested in standardized EuroNCAP Car-to-Car Rear (CCR) collision scenario, implemented on the static
Alfatti, Federico, Garinei, Michele, Annicchiarico, Claudio, Capitani, Renzo
Hardware-in-the-loop testing of a hybrid Brake-by-wire system for electric vehicleSAE-PP-002403/1/2022
Recent trends in automotive engineering, such as electrification and automation, are opening chances as well as challenges due to the need of new chassis components (e.g., drivetrain, brakes, steering, suspension etc.) and control methods. Mechatronic components, so called X-by-wire systems, seem to become game-changers since they allow more efficient vehicle control with a higher operational speed for improving active safety, efficiency and driving comfort. Especially brake-by-wire (BBW) applications step into foreground, since they affect the bespoken aspects but have a limited use on serial vehicles yet due to the current maturity and the high impact of the systems on vehicle architecture. On the other hand, those systems have many advantages e.g., adjustable pedal feel, continuous wheel slip control and more effective recuperation of brake energy. Electromechanical brakes (EMBs) do not need brake fluid which make them easier to integrate (no pipes, no bleeding) and increase
Heydrich, Marius, Ivanov, Valentin, Bertagna, Alessandro, Rossi, Alessadro, Mazzoni, Matteo, Büchner, Florian
Vehicle System Integration (Electric Parking Brake)2021-36-04142/10/2022
The initial step to implement the brake-by-wire on vehicles is to replace the conventional mechanical parking brake with an Electric Parking Brake (EPB). This paper aims to share the experience in integrating the EPB into the vehicle with respect to design and validation points of view. It starts by introducing the EPB in comparison with the conventional mechanical parking brake, showing two kinds of EPB: with a drum brake (EPB-Si, Simplex integrated) and with a caliper (EPB-Ci, Caliper integrated). In sequence, it explains the most important EPB functions. After a basic knowledge introduction, it describes the integration process, separating into 3 different levels: mechanical, electrical, and software, having a brief description that includes some lessons learned from each one. Two parts compose the EPB system: drum brake or caliper with Motor Gear Unit (MGU) and the software to control it, Parking Brake Controller (PBC) library, running into the Electronic Stability Control (ESC
Dias, Fábio Gaiotto, Minutti, Carlos José, Menezes, Fabricio Oliveira
Active Safety Control of X-by-Wire Electric Vehicles: A Survey10-06-02-00081/24/2022
This article presents a survey on active safety control of X-by-wire electric vehicles. The steer-by-wire (SBW) system, brake-by-wire (BBW) system, and electric drive system are three critical techniques for X-by-wire electric vehicles. As to the three systems, the structure comparison and performance analysis of existing products and prototypes are conducted. Then two kinds of X-by-wire chassis configuration, i.e., the centralized type and the distributed type, are introduced. For active safety control, various control models are summarized, including vehicle dynamics model, single-track model, path tracking model, and wheel dynamics model. Based on the proposed model, different active safety control algorithms are introduced involving longitudinal dynamics control, handling stability control, rollover prevention control, path tracking control, and active fault-tolerant control. In addition, some data-driven approaches for active safety control of X-by-wire electric vehicles are
Peng, Hang, Chen, Xinbo
E-Mobility-Opportunities and Challenges of Integrated Corner Solutions2021-01-09844/6/2021
E-mobility is a game changer for the automotive domain. It promises significant reduction in terms of complexity and in terms of local emissions. With falling prices and recent technological advances, the second generation of electric vehicles (EVs) that is now in production makes electromobility an affordable and viable option for more and more transport mission (people, freight). Current e-vehicle platforms still present architectural similarities with respect to combustion engine vehicle (e.g., centralized motor). Target of the European project EVC1000 is to introduce corner solutions with in-wheel motors supported by electrified chassis components (brake-by-wire, active suspension) and advanced control strategies for full potential exploitation. Especially, it is expected that this solution will provide more architectural freedom toward “design-for-purpose” vehicles built for dedicated usage models, further providing higher performances. Target of this paper are (a) to introduce
Armengaud, Eric, Eitzinger, Stefan, Pirker, Hannes, Buh, Joze, Gramstat, Sebastian, Heimann, Stefan, Chen, Chiara, Ivanov, Valentin, Heydrich, Marius, Sorniotti, Aldo, Gruber, Patrick, Tavernini, Davide
A Passenger Car Brake Pedal Feel Analysis Model Based on Integrated Brake by Wire System2021-01-09754/6/2021
The fully decoupled brake by wire system is a complex system consisting of mechanical components such as springs and rubber and hydraulic structural components coupled together. Compared to conventional braking systems, it is characterized by the full decoupling of the brake pedal from the brake wheel cylinders in normal braking mode, and the pressure fluctuations in the wheel cylinders do not affect the pedal feel. In order to predict brake pedal feel in a passenger car, a dynamic model was developed for both normal and backup braking modes, taking into account the variation of the volume modulus of the brake fluid and the frictional forces of the master cylinder pistons. The influence of different pedal input speeds on the pedal feel characteristic curve was analyzed using static vehicle tests and the related parameters of the braking system were identified in order to correct the design data. Subsequently, a dynamic test of the vehicle pedal feel was conducted to establish a
Yin, Faguo, Wang, Minghui, Jiang, Yongfeng, Kang, Yingzi
Numerical Investigation of Solenoid Valve Flow Field in Decoupled Brake-by-Wire System2021-01-08064/6/2021
The decoupling brake-by-wire system controls the key components of the flow path and liquid flow of the whole brake system through the solenoid valve of the bottom control unit. The reference cross-sectional area value at the valve inlet is obtained by calculation, and the valve body structure model is established. The flow channel structure is extracted, and the porous media model is used to replace the fluid area of the filter screen at the entrance of the solenoid valve. The Fluent software is used to analyze the influence on the flow characteristics of the solenoid valve with or without a filter. The accuracy of the model is verified by the experimental results, which also show that the porous medium can effectively and accurately reflect the characteristics of the solenoid valve end filter. Based on the simulation model, the influences of parameters such as the diameter of the solenoid valve inlet, cone angle and spool stroke on the internal flow field characteristics of the
wan, liping, Wang, Minghui, Jiang, Yongfeng, Zhao, Xuezhi
Electronic Control of Brake and Accelerator Pedals for Precise Efficiency Testing of Electrified Vehicles2020-01-12824/14/2020
Efficiency testing of hybrid-electric vehicles is challenging, because small run-to-run differences in pedal application can change when the engine fires or the when the friction brakes supplement regenerative braking, dramatically affecting fuel use or energy regeneration. Electronic accelerator control has existed for years, thanks to the popularity of throttle-by-wire (TBW). Electronic braking control is less mature, since most vehicles don’t use brake-by-wire (BBW). Computer braking control on a chassis dynamometer typically uses a mechanical actuator (which may suffer backlash or misalignment) or braking the dynamometer rather than the vehicle (which doesn’t yield regeneration). The growth of electrification and autonomy provides the means to implement electronic brake control. Electrified vehicles use BBW to control the split between friction and regenerative braking. Automated features, e.g. adaptive cruise control, require BBW to actuate the brakes without pedal input. We
Gross, Michael C., Hamermesh, Jonathan, Jonson, Kyle, Alden, Joshua
Research on Compensation Redundancy Control for Basic Force Boosting Failure of Electro-Booster Brake System2020-01-02164/14/2020
As a new brake-by-wire solution, the electro-booster (Ebooster) brake system can work with the electronic stability program (ESP) equipped in the real vehicle to realize various excellent functions such as basic force boosting (BFB), active braking and energy recovery, which is promoting the development of smart vehicles. Among them, the BFB is the function of Ebooster's servo force to assist the driver's brake pedal force establishing high-intensity braking pressure. After the BFB function failure of the Ebooster, it was not possible to provide sufficient brake pressure for the driver's normal braking, and eventually led to traffic accidents. In this paper, a compensation redundancy control strategy based on ESP is proposed for the BFB failure of the self-designed Ebooster. Firstly, introduced the working principle of Ebooster and ESP, and a suitable pressure-building circuit was selected for the dual brake actuator system; Secondly, after the BFB failure of Ebooster, the rule-based
Zhao, Jian, Chen, Zhicheng, Zhu, Bing, Wu, Jian
Research on Yaw Stability Control of Unmanned Vehicle Based on Integrated Electromechanical Brake Booster2020-01-02124/14/2020
The Electromechanical Brake Booster system (EMBB) integrates active braking and energy recovery and becomes a novel brake-by-wire solution that substitutes the vacuum booster. While the intelligent unmanned vehicle is in unstable state, the EMBB can improve the vehicle yaw stability more quickly and safely. In this paper, a new type of integrated EMBB has been designed, which mainly includes two parts: servo motor unit and hydraulic control unit. Aiming at the dynamic instability problem of intelligent unmanned vehicle, a three-layer vehicle yaw stability control structure including decision layer, distribution layer and execution layer is proposed based on integrated EMBB. Firstly, the decision layer calculates the ideal yaw rate and the side slip angle of the vehicle with the classic 2DOF vehicle dynamics model. The boundary of the stable region is determined by the phase plane method and the additional yaw moment is determined by the feedback PI control algorithm. Secondly, the
Lao, Dexing, Wu, Jian, He, Rui, Zhu, Bing, Zhao, Jian, Chen, Zhicheng
Modelling and Performances of Hydraulic Magnetorheological Fluid Damper with Modified Bi-Viscosity Model2020-01-09884/14/2020
A hydraulic chamber is embedded in serial with the accumulator of a normal mono-tube magnetorheological fluid damper (MRFD). The damper stiffness can be adjusted by changing the accumulator volume with the hydraulic chamber. The hydraulic chamber is connected to an electric pump and controlled by the braking-by-wire (BBW) system. A modified bi-viscosity magnetorheological fluid (MRF) model that explicitly includes the parameter of control current is proposed. A dynamic model of this hydraulic MRFD is subsequently set up based on the MRF model. Experiments are conducted to validate the model and simulations are carried out to study the influences of accumulator volume on the external performances. Results show that the hydraulic chamber is able to provide rapid variations of the external force through accumulator volume changes.
Xiong, Cenbo, Yu, Liangyao, Li, Zhenchuan, Lu, Zhenghong, Lanie, Abi
Analysis of Active Collision Avoidance Performance Based on Cooperative Regenerative Auxiliary Braking System2019-01-502711/4/2019
Active collision avoidance can assist drivers to avoid longitudinal collision through active brake. Regenerative braking can improve the driving range and braking response speed. At this stage, conventional hydraulic braking system limits the implements of above technologies because of its poor performance of response speed and coordinated control. While the brake-by-wire system is a better actuator that can fulfill requirements of automotive electric and intelligent development due to its rapid response and flexible adjustment. However, the system control algorithm becomes more complicated with introduction of regenerative braking and active collision avoidance function, which is also the main problem solved in this paper. First, a new type of cooperative regenerative auxiliary braking system (CRABS) of intelligent electric vehicles, which integrates the functions of brake-by-wire, regenerative braking and active collision avoidance, is proposed, for purpose of analyzing the
Hou, Xiaohui, Zhang, Junzhi, Zhang, Zhongshi, He, Chengkun
A Drive-by-Wire Conversion of an FMVSS-500 Vehicle for Autonomous Driving Applications2019-01-07044/2/2019
Autonomous driving has witnessed many developments in the past decade. Most automotive manufacturers and technology companies have been investing in the software and platform development of these vehicles, and long strides have been made in this domain. Nonetheless, academia has been partially isolated from the practical efforts of these developments, due to the cost involved in converting a standard vehicle into a drive-by-wire platform suitable for self-driving vehicular research. In this paper, a low-cost autonomous vehicle platform is developed and the process for converting a Polaris Gem e2 FMVSS-500 vehicle to brake-by-wire, throttle-by-wire, and steer-by-wire is elaborated. The tools and the procedures followed here were all conducted by students, in house, and can be easily duplicated for other FMVSS-500 compatible vehicles. Discussions include the interface of an embedded controller for an electric power steering system, electronic control of hydraulic brake pressure, and
Yeranosian, Viken, Patel, Nayan, Vega, Joseph, Mohammad, Utayba, Paulik, Mark, Santora, Michael
Recommended Practice for Identification of Standardized Truck and Tractor Electrical CircuitsJ2191_201901 (Historical)1/8/2019
This SAE document defines a recommended practice for implementing circuit identification for electrical power and signal distribution systems of the Class 8 trucks and tractors. This document provides a description of a supplemental circuit identifier that shall be utilized in conjunction with the original equipment manufacturer’s primary circuit identification as used in wire harnesses but does not include electrical or electronic devices which have pigtails. The supplemental circuit identifier is cross-referenced to a specified subsystem of the power and signal distribution system identified in Section 5.
Truck and Bus Electrical Systems Committee
Items per page:
1 – 50 of 124