Articles de revues : « Active Braking »

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Fecher, Norbert, Jens Hoffmann, Hermann Winner, Klaus Fuchs, Bettina Abendroth et Ralph Bruder. « Active hazard braking ». ATZ worldwide 112, n^o 11 (novembre 2010) : 40–46. http://dx.doi.org/10.1007/bf03225059.

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Lin, Chun-Liang, Hao-Che Hung et Jia-Cheng Li. « Active Control of Regenerative Brake for Electric Vehicles ». Actuators 7, n^o 4 (1 décembre 2018) : 84. http://dx.doi.org/10.3390/act7040084.

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Looking at new trends in global policies, electric vehicles (EVs) are expected to increasingly replace gasoline vehicles in the near future. For current electric vehicles, the motor current driving system and the braking control system are two independent issues with separate design. If a self-induced back-EMF voltage from the motor is a short circuit, then short-circuiting the motor will result in braking. The higher the speed of the motor, the stronger the braking effect. However, the effect is deficient quickly once the motor speed drops quickly. Traditional kinetic brake (i.e., in the short circuit is replaced by a resistor) and dynamic brake (the short circuit brake is replaced by a capacitor) rely on the back EMF alone to generate braking toque. The braking torque generated is usually not enough to effectively stop a rotating motor in a short period of time. In this research task, an integrated driving and braking control system is considered for EVs with an active regenerative braking control system where back electromagnetic field (EMF), controlled by the pulse-width modulation (PWM) technique, is used to charge a pump capacitor. The capacitor is used as an extra energy source cascaded with the battery as a charge pump. This is used to boost braking torque to stop the rotating motor in an efficient way while braking. Experiments are conducted to verify the proposed design. Compared to the traditional kinetic brake and dynamic brake, the proposed active regenerative control system shows better braking performance in terms of stopping time and stopping distance.

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Kertész, József, et Tünde Anna Kovács. « Impact Energy Absorbtion by Active Braking ». Műszaki Tudományos Közlemények 16, n^o 1 (1 avril 2022) : 36–42. http://dx.doi.org/10.33894/mtk-2022.16.07.

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Abstract Due to urbanization and the significantly increasing number of vehicles, urban roads are becoming more congested day by day, with the result that the rear-end collision has become the third most common type of collision. By developing and integrating active and passive safety systems, car manufacturers are working to prevent accidents and reduce the consequences of an accident. The present study examines a braking procedure and its applicability based on the integration of a passive and active safety system and provides development guidelines for the reduction of personal injuries and property damage in the event of a rear-end accident.

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CHEN, Deling. « ACTIVE FRONT STEERING DURING BRAKING PROCESS ». Chinese Journal of Mechanical Engineering (English Edition) 21, n^o 04 (2008) : 64. http://dx.doi.org/10.3901/cjme.2008.04.064.

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Chu, Liang, Yi Yang, Chong Guo, Yu Ting Huang et Wen Hui Li. « Research on the Active Pressurization Control Method of RBS ». Applied Mechanics and Materials 644-650 (septembre 2014) : 4864–68. http://dx.doi.org/10.4028/www.scientific.net/amm.644-650.4864.

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This paper based on the regenerative braking system, which developed in the '863' project, designed pressure control method for RBS system in the condition of active pressurization state and conduct Bench experiments. The results show that, under the condition of high frequency, through modulation frequency of the pulse signal and duty ratio method can coordinate the regenerative braking and hydraulic braking force, meet target pressure and the pressurization rate requirements of RBS.

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Zhang, Lu, Guo Ye Wang, Guo Yan Chen et Zhong Fu Zhang. « The Vehicles ESP Test System Based on Active Braking Control ». Advanced Materials Research 588-589 (novembre 2012) : 1552–59. http://dx.doi.org/10.4028/www.scientific.net/amr.588-589.1552.

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This paper proposes an active braking control dynamical system in order to establish a safe and efficient vehicle driving stability control test system. Aiming at Chery A3 sedan, set up the active braking control dynamic simulation system base on MATLAB/Simulink. Adopting the brake driving integration ESP control strategy, analyze and verify the stability control performance of independent vehicle system and vehicle ESP test system based on active braking control respectively in under steering and excessive steering two test conditions. The analyzing results indicate that the test system based on active braking control can effectively assist vehicle travelling in the absence of ESP control or ESP control system failure; when vehicle has ESP control system, the driving stability control performance of this system and independent vehicle system has remarkable consistency. The active braking control system provides a basis for research of vehicle driving stability control test.

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Wu, Wenguang, Debiao Zou, Jian Ou et Lin Hu. « Adaptive Cruise Control Strategy Design with Optimized Active Braking Control Algorithm ». Mathematical Problems in Engineering 2020 (21 juillet 2020) : 1–10. http://dx.doi.org/10.1155/2020/8382734.

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The braking quality is considered as the most important performance of the adaptive control system that influences the vehicle safety and ride comfort remarkably. This research is aimed at designing an adaptive cruise control (ACC) system based on active braking algorithm using hierarchical control. Taking into account the vehicle with safety and comfort, the upper decision-making controller is designed based on model predictive control algorithm. Throttle controller and braking controller are designed with feedforward and feedback algorithms as the bottom controller, where the braking controller is designed based on the hydraulic braking model. The whole model is simulated collaboratively with Amesim, Carsim, and Simulink. By comparison with the full deceleration model, the results show that the proposed algorithm can not only make the vehicle maintain a safe distance under the premise of following the target vehicle ahead effectively but also provide favorable driving comfort.

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Xu, Fengrui, Mengqiao Chen, Xuelin Liang et Wensheng Liu. « PSO Optimized Active Disturbance Rejection Control for Aircraft Anti-Skid Braking System ». Algorithms 15, n^o 5 (10 mai 2022) : 158. http://dx.doi.org/10.3390/a15050158.

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A high-quality and secure touchdown run for an aircraft is essential for economic, operational, and strategic reasons. The shortest viable touchdown run without any skidding requires variable braking pressure to manage the friction between the road surface and braking tire at all times. Therefore, the manipulation and regulation of the anti-skid braking system (ABS) should be able to handle steady nonlinearity and undetectable disturbances and to regulate the wheel slip ratio to make sure that the braking system operates securely. This work proposes an active disturbance rejection control technique for the anti-skid braking system. The control law ensures action that is bounded and manageable, and the manipulating algorithm can ensure that the closed-loop machine works around the height factor of the secure area of the friction curve, thereby improving overall braking performance and safety. The stability of the proposed algorithm is proven primarily by means of Lyapunov-based strategies, and its effectiveness is assessed by means of simulations on a semi-physical aircraft brake simulation platform.

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Zhang, Lei, En Guo Dong et Jie Xun Lou. « Conjoint Simulation of Active Suspension and ABS ». Applied Mechanics and Materials 494-495 (février 2014) : 155–58. http://dx.doi.org/10.4028/www.scientific.net/amm.494-495.155.

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A conjoint simulation of suspension system and brake system is proposed based on vehicle braking performance and ride stability. A half car simulation model is built applying the software of MATLAB in which the dynamic load is used to control the active force for suspension system and adjust parameter value of ABS (Anti-lock brake system). The suspension system and ABS construction of the half car simulation model is illustrated in detail. Using the simulation model, the braking distance, the stroke for suspension and the pitch angle of body are measured in three status which include the individually control for active suspension, the individually control for ABS and the integration control respectively. The simulation data show that the integral control method synchronously ensures braking stability and riding stability.

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Anh, An Thi Hoai Thu, et Luong Huynh Duc. « A regenerative braking energy recuperation from elevator operation in building by active rectifier ». International Journal of Power Electronics and Drive Systems (IJPEDS) 12, n^o 2 (1 juin 2021) : 811. http://dx.doi.org/10.11591/ijpeds.v12.i2.pp811-821.

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Elevators- means of vertical transportation to carry people and goods are an indispensable part in offices, high-rise buildings, hospitals, commercial areas, hotels, car-parks when blooming urbanization develops worldwide. However, the level of energy consumption in elevator operation is significant, so energy saving solutions have been outlined and applied in practice. With frequent braking phases, regenerative braking energy is wasted on braking resistors. Therefore, this paper proposes regenerative braking energy recuperation method for elevator operation in building by active rectifiers enabling the braking energy to be fed back into utility grid. Simulation results conducted by MATLAB with data collected from OCT5B building-RESCO new urban area, Ha noi, Vietnam have verified saving energy of using active rectifiers replacing diode rectifiers up to 33%.

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Tấn, Vũ Văn. « ADVANCED CONTROLLER DESIGN FOR ACTIVE BRAKING SYSTEMS ». TNU Journal of Science and Technology 225, n^o 13 (30 novembre 2020) : 78–85. http://dx.doi.org/10.34238/tnu-jst.3572.

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Bài báo này trình bày tổng hợp bộ điều khiển nâng cao cho hệ thống phanh chủ động trên ô tô tải, bằng cách kết hợp phương pháp H∞ với mô hình hệ thống có thông số thay đổi tuyến tính LPV. Vận tốc chuyển động và hệ số chuyển tải ở cầu sau được xem xét là hai thông số thay đổi. Phương pháp LPV dựa trên cách tiếp cận chia lưới được sử dụng để tổng hợp bộ điều khiển H∞/LPV. Để điều chỉnh hệ thống phanh chủ động đáp ứng được với các nguy cơ lật ngang của ô tô, hàm trọng số phụ thuộc vào gia tốc ngang được xem là thông số quan trọng nhất. Kết quả mô phỏng trong miền tần số cho thấy việc sử dụng hệ thống phanh chủ động điều khiển H∞/LPV đã làm giảm đáng kể độ lớn hàm truyền từ góc đánh lái đến hệ số chuyển tải ở hai cầu xe, điều này đã chứng minh hiệu quả của phương pháp đề xuất.

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Krolik, Julian H., et Avery Meiksin. « Fueling active galactic nuclei by magnetic braking ». Astrophysical Journal 352 (avril 1990) : L33. http://dx.doi.org/10.1086/185687.

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Soltani, Abbas, Ahmad Bagheri et Shahram Azadi. « Integrated vehicle dynamics control using semi-active suspension and active braking systems ». Proceedings of the Institution of Mechanical Engineers, Part K : Journal of Multi-body Dynamics 232, n^o 3 (9 octobre 2017) : 314–29. http://dx.doi.org/10.1177/1464419317733186.

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This article presents an integrated control of yaw, roll and vertical dynamics based on a semi-active suspension and an electronic stability control with active differential braking system. During extreme manoeuvres, the probability of vehicle rollover is increased and the stability of lateral and yaw vehicle motions is deteriorated because of the saturation of tyre forces. Furthermore, when the road excitation frequencies are equal to the natural frequencies of the unsprung masses, the resonance phenomena occurs, which causes some oscillations getting revealed on responses of the yaw and lateral vehicle dynamics. In these situations, the active braking alone cannot be helpful to improve the vehicle handling and stability, considerably. In order to overcome these difficulties, a coordinated control of the semi-active suspension and the active braking is proposed, using a fuzzy controller and an adaptive sliding mode controller, respectively. A non-linear full vehicle model with 14 degrees of freedom is established and combined with the modified Pacejka tyre model. As the majority of vehicle dynamics variables and the road profile inputs cannot be measured in a cost-efficient way, a non-linear estimator based on unscented Kalman filter is designed to estimate the entire vehicle dynamics states and the road unevenness. Simulation results of the steering manoeuvres on the random road inputs show that the proposed chassis system can effectively improve the vehicle handling, stability and ride comfort.

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Lal, Roop, R. C. Singh, Vaibhav Sharma et Vaibhav Jain. « A Study of Active Brake System of Automobile ». International Journal of Advance Research and Innovation 5, n^o 2 (2017) : 165–71. http://dx.doi.org/10.51976/ijari.521729.

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There are many situations where the driver’s response is not fast enough to apply brakes to stop and control the vehicle during emergency. So in such cases, there is an urgent need for an active brake system. Brake assist is an active vehicle safety feature designed not only to help drivers come to a stop more quickly during an episode of emergency braking but it automatically applies brakes in case the car in front of car comes too close. There are many sensors along with camera which continuously determines the speed of car in front of our car .If both cars come too close to each other, then brake assist first warns the driver and then apply 20% to 40% of braking capacity automatically and if still driver does not respond it activates emergency brake assist which applies 100% of braking power .During this ABS and EBD (sometimes ESC and TRACTION CONTROL) also comes into play which provides easy manoeuvre control to driver over vehicle.

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Yang, Yu, Yang Liu et Chao Wang. « Development and Validation of AEBS Anti-slip Control Model for In-wheel Motor Drive EV in AMESim Co-simulation with Matlab/Simulink ». Journal of Physics : Conference Series 2219, n^o 1 (1 avril 2022) : 012013. http://dx.doi.org/10.1088/1742-6596/2219/1/012013.

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Abstract The Advanced Emergency Braking System (AEBS) is an intelligent vehicle active safety system to avoid certain sorts of collisions. Recent researches on AEBS emphasized radar, lasers and video camera technologies mostly, also controller developments were studied from Vehicle to Vehicle (V2V) to Vehicle to Pedestrian(V2P) and other aspects with different scenarios, aiming to enhance the active safety of the vehicle. However, most of the current systems focus little on braking performance of AEBS, especially for EV with distributed drive system, like in-wheel motors. In this paper, A 15 Degree of Freedom (DOF) distributed drive Electric Vehicle (EV) model was created and an Anti-slip Controller of AEBS based on the logic threshold method was built. To validate this control strategy, a co-simulation platform between Simulink and AMESim was established and vehicle braking dynamic of four in-wheel motor drive EV was evaluated. Results display that the designed controller not only enhanced the braking performance of AEBS under sudden braking on slippery surface condition, but also meet the requirement of UNECE braking regulation which has practical meanings in boosting active safety of a four in-wheel motor drive EV and development of industrialization.

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Kremer, Christina, Markus Tomzig, Nora Merkel et Alexandra Neukum. « Using Active Seat Belt Retractions to Mitigate Motion Sickness in Automated Driving ». Vehicles 4, n^o 3 (11 août 2022) : 825–42. http://dx.doi.org/10.3390/vehicles4030046.

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The introduction of automated-driving functions provides passengers with the opportunity to engage in non-driving related tasks during the ride. However, this benefit might be compromised by an increased incidence of motion sickness. Therefore, we investigated the effectiveness of active seat belt retractions as a countermeasure against motion sickness during inattentive automated driving. We hypothesized that seat belt retractions would mitigate motion sickness by supporting passengers to anticipate upcoming braking maneuvers, by actively tensioning their neck muscles and, thereby, reducing the extent of forward head movement while braking. In a motion base driving simulator, 26 participants encountered two 30 min automated drives in slow-moving traffic: one drive with active seat belt retractions before each braking maneuver and a baseline drive without. The results revealed that there was no difference in perceived motion sickness between both experimental conditions. Seat belt retractions resulted in an increased activity of the lateral neck muscles and supported drivers to anticipate braking maneuvers. However, at the same time, the retractions led to an increased magnitude of head movement in response to braking. This research lays the groundwork for future research on active seat belt retractions as a countermeasure against motion sickness and provides directions for future work.

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Shirshakov, A. E., I. A. Grudev, V. N. Likhachev et P. E. Rozin. « Active Braking for Soft Landing on the Surface of Mars : Part 2 : Braking Control ». Solar System Research 55, n^o 7 (décembre 2021) : 642–52. http://dx.doi.org/10.1134/s0038094621070182.

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Žuraulis, Vidas, Vytenis Surblys et Eldar Šabanovič. « TECHNOLOGICAL MEASURES OF FOREFRONT ROAD IDENTIFICATION FOR VEHICLE COMFORT AND SAFETY IMPROVEMENT ». Transport 34, n^o 3 (27 mai 2019) : 363–72. http://dx.doi.org/10.3846/transport.2019.10372.

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This paper presents the technological measures currently being developed at institutes and vehicle research centres dealing with forefront road identification. In this case, road identification corresponds with the surface irregularities and road surface type, which are evaluated by laser scanning and image analysis. Real-time adaptation, adaptation in advance and system external informing are stated as sequential generations of vehicle suspension and active braking systems where road identification is significantly important. Active and semi-active suspensions with their adaptation technologies for comfort and road holding characteristics are analysed. Also, an active braking system such as Anti-lock Braking System (ABS) and Autonomous Emergency Braking (AEB) have been considered as very sensitive to the road friction state. Artificial intelligence methods of deep learning have been presented as a promising image analysis method for classification of 12 different road surface types. Concluding the achieved benefit of road identification for traffic safety improvement is presented with reference to analysed research reports and assumptions made after the initial evaluation.

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Bai, Zhenyuan, Yufeng Lu et Yunxia Li. « Method of Improving Lateral Stability by Using Additional Yaw Moment of Semi-Trailer ». Energies 13, n^o 23 (30 novembre 2020) : 6317. http://dx.doi.org/10.3390/en13236317.

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The lateral stability control of tractor semi-trailer plays a vital role for enhancing its driving safety, and the distributed electric drive structure of a hub motor creates opportunities and challenges for realising the lateral stability accurately. Based on the dynamics simulation software TruckSim, a nonlinear dynamic tractor semi-trailer model is established, and a MATLAB/Simulink linear three-degree-of-freedom monorail reference model is established. The upper controller adopts fuzzy proportional–integral–derivative control to export active yaw torque values of the tractor and semi-trailer. The lower controller outputs the driving/braking torque of each wheel according to the target wheel driving/braking rules and torque distribution rules. The tractor produce an active yaw torque through conventional differential braking the hub motor is installed on both sides of the semi-trailer, and the active yaw torque is produced by the coordinated control of the driving/braking torque of the hub motor and the differential braking of the mechanical braking system. To prevent wheel locking, the slip rate of each wheel is controlled. Finally, based on the TruckSim–MATLAB/Simulink cosimulation platform, cosimulation is performed under typical working conditions. The simulation results show that the control strategy proposed in this report is superior to the conventional differential braking control (ESP). It can not only improve the lateral stability of the vehicle more effectively, but also improve the roll stability.

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Zhang, Junjiang, Yang Yang, Minghui Hu, Chunyun Fu et Jun Zhai. « Model Predictive Control of Active Suspension for an Electric Vehicle Considering Influence of Braking Intensity ». Applied Sciences 11, n^o 1 (23 décembre 2020) : 52. http://dx.doi.org/10.3390/app11010052.

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In the process of vehicle braking, braking intensity has a significant impact on vehicle comfort, and studies on this aspect have been limited. Therefore, an equivalent 4-degree-of-freedom half-vehicle model including the braking intensity influence was established in this study. Subsequently, considering braking intensity as the interference quantity that is the uncontrollable input, a model predictive control (MPC) strategy in which the vertical velocities of front body, rear body, front wheel, and rear wheel are the control targets was proposed. Based on Lyapunov’s stability theory, the stability of the MPC system was proven. Finally, a dual-loop control (DLC) strategy was used for comparison to verify the superiority of the MPC strategy. The results indicate that compared with the DLC strategy under the gradual braking condition, the root mean square of the front and rear body vertical velocities, body pitch angle, and body pitch angle velocity under the MPC strategy were all reduced by more than 70%, thus improving the ride comfort of the vehicle.

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Hong, Liang, Liang Li et Ruhai Ge. « Active Braking Strategy Considering VRU Motion States in Curved Road Conditions ». Machines 11, n^o 1 (11 janvier 2023) : 100. http://dx.doi.org/10.3390/machines11010100.

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Currently, the active braking system is primarily used to avoid collisions between vehicles and vulnerable road users (VRUs) traversing the road at a constant speed in straight road conditions. Research on the collision avoidance strategy has been conducted to enhance the protective effects of the active braking system for VRUs traversing the road in various motion states in curved road conditions. Firstly, the spatial position relationships between VRUs and turn-taking vehicles are established when VRUs traverse the road in various motion states from the outside or the inside of the curved road; a mathematical model is established to identify whether VRUs are in a dangerous condition. Secondly, the safe distance model is established to formulate the vehicle collision avoidance strategy. Thirdly, the active braking controller is designed based on the upper sliding mode control and the lower discrete PID control. Finally, the six collision test scenarios on the curved road are constructed by utilizing the Prescan and Matlab/Simulink software. The results show that the active braking system can avoid the collision between the vehicle and VRUs traversing the curved road in various motion states.

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Sun, Dongsheng, Junzhi Zhang, Chengkun He et Jinheng Han. « Dual-mode regenerative braking control strategy of electric vehicle based on active disturbance rejection control ». Proceedings of the Institution of Mechanical Engineers, Part D : Journal of Automobile Engineering 235, n^o 6 (17 janvier 2021) : 1483–96. http://dx.doi.org/10.1177/0954407020985642.

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The traditional regenerative braking control strategy usually uses the torque control mode and does not perform closed-loop control on the charging current, when the vehicle needs to be charged with a small current, the regenerative braking system cannot work effectively. The dual-mode regenerative braking control strategy proposed in this paper unifies the closed-loop control of regenerative current and the closed-loop control of regenerative torque. Especially when the battery is in a state of high charge or the temperature of the battery is too high or too low, this strategy can ensure charging safety, regeneration efficiency, and ride comfort. In the current closed-loop control mode, this proposal uses the ADRC controller to dynamically adjust the motor torque to achieve the purpose of accurately controlling the regenerative current. This method does not need to change the original vector control frame of the motor, which is convenient for engineering applications. The designed regenerative control strategy is verified through typical braking simulation. Bench tests are carried out and the results validate the feasibility and effectiveness of the designed strategy. Based on the realization of the safety of charging and the vehicle ride comfort, the proposed regenerative braking control strategy can achieve higher regeneration efficiency under the dynamical limitation of battery charging current, which further expands the operating range of the regenerative braking system.

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English, James D., et Anthony A. Maciejewski. « Failure Tolerance through Active Braking : A Kinematic Approach ». International Journal of Robotics Research 20, n^o 4 (avril 2001) : 287–99. http://dx.doi.org/10.1177/02783640122067408.

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Sharp, R. S., et M. A. Alonso Fernández. « Car—caravan snaking : Part 2 : Active caravan braking ». Proceedings of the Institution of Mechanical Engineers, Part C : Journal of Mechanical Engineering Science 216, n^o 7 (1 juillet 2002) : 723–36. http://dx.doi.org/10.1243/09544060260128779.

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Founded on the review and results of Part 1, Part 2 contains a description of the virtual design of an active braking system for caravans or other types of trailer, to suppress snaking vibrations, while being simple from a practical viewpoint. The design process and the design itself are explained. The performance is examined by simulations and it is concluded that the system is effective, robust and realizable with modest and available components.

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Zhang, Rui, Jun Peng, Bin Chen, Kai Gao, Yingze Yang et Zhiwu Huang. « Prescribed Performance Active Braking Control with Reference Adaptation for High-Speed Trains ». Actuators 10, n^o 12 (26 novembre 2021) : 313. http://dx.doi.org/10.3390/act10120313.

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Active braking control systems are vital for the safety of high-speed trains by leading the train operation at its maximum adhesion state. The train adhesion is a nonlinear function of the slip ratio and varies with the uncertain wheel-rail contact conditions. A nonlinear active braking control with rapid and accurate tracking performance is highly required for train braking systems. This paper proposes a novel prescribed performance active braking control with reference adaptation to obtain the maximum adhesion force. The developed feedback linearization controller employs a prescribed performance function that specifies the convergence rate, steady-state error, and maximum overshoot to ensure the transient and steady-state control performance. Furthermore, in the designed control approach, a continuous-time unscented Kalman filter is introduced to estimate the uncertainty of wheel-rail adhesion. The estimation is utilized to represent uncertainty and compensate for the prescribed performance control law. Finally, based on the estimated wheel-rail adhesion, an on-line optimal slip ratio generation algorithm is proposed for the adaptation of the reference wheel slip. The stability of the system is provided, and experiment results validate the effectiveness of the proposed method.

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Yang, Wei, Xiang Zhang, Qian Lei et Xin Cheng. « Research on Longitudinal Active Collision Avoidance of Autonomous Emergency Braking Pedestrian System (AEB-P) ». Sensors 19, n^o 21 (28 octobre 2019) : 4671. http://dx.doi.org/10.3390/s19214671.

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The AEB-P (Autonomous Emergency Braking Pedestrian) system has the functional requirements of avoiding the pedestrian collision and ensuring the pedestrian’s life safety. By studying relevant theoretical systems, such as TTC (time to collision) and braking safety distance, an AEB-P warning model was established, and the traffic safety level and work area of the AEB-P warning system were defined. The upper-layer fuzzy neural network controller of the AEB-P system was designed, and the BP (backpropagation) neural network was trained by collected pedestrian longitudinal anti-collision braking operation data of experienced drivers. Also, the fuzzy neural network model was optimized by introducing the genetic algorithm. The lower-layer controller of the AEB-P system was designed based on the PID (proportional integral derivative controller) theory, which realizes the conversion of the expected speed reduction to the pressure of a vehicle braking pipeline. The relevant pedestrian test scenarios were set up based on the C-NCAP (China-new car assessment program) test standards. The CarSim and Simulink co-simulation model of the AEB-P system was established, and a multi-condition simulation analysis was performed. The results showed that the proposed control strategy was credible and reliable and could flexibly allocate early warning and braking time according to the change in actual working conditions, to reduce the occurrence of pedestrian collision accidents.

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Zhang, Shuai, Bin Lei, Shuai Chen et Lei Sha. « Research on subjective evaluation method of automatic emergency braking (AEB) for passenger car ». E3S Web of Conferences 268 (2021) : 01037. http://dx.doi.org/10.1051/e3sconf/202126801037.

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With the continuous development of automotive active safety technology, automatic emergency braking technology has been widely used, playing an important role in avoiding rear-end collisions or collisions with pedestrians and other traffic participants. This article analyzes the technical characteristics of the automatic emergency braking system, put forward subjective evaluation index, select vehicle-to-vehicle, vehicle -to-pedestrian and other typical scenes for automatic emergency braking subjective evaluation and actual vehicle verification, and constructed a subjective evaluation system for automatic emergency braking of passenger car.

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Li, Xuefei, Jian Li, Lida Su et Yue Cao. « Control Methods for Roll Instability of Articulated Steering Vehicles ». Mathematical Problems in Engineering 2016 (2016) : 1–14. http://dx.doi.org/10.1155/2016/8041816.

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This study examines the control methods for roll instability of articulated steering vehicles (ASVs) by taking wheel loaders as the research object. An eight-degrees-of-freedom nonlinear dynamics model of ASVs was built on the basis of multibody dynamics. Three methods, namely, active braking (the front and rear axles have the same braking torque), active steering, and adjusting the swing bridge (applying a control torque between the rear body and rear axle), were adopted to analyze the effects on the roll stability of ASVs through the dynamic model. The results show that active braking is conducive to the roll stability of ASVs during turning, active steering can improve the roll stability of ASVs during turning and passing over obstacles, and adjusting the swing bridge can improve the roll stability of ASVs by changing the vehicle posture and the position of the gravity center.

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Kalinichenko, Yevgeniy, Mykhaylo Kourov et Kateryna Volovyk. « MANEUVER FOR STOPPING THE SHIP IN A SET POINT BY ACTIVE OR PASSIVE BRAKING AND CONCIDERING THE CURRENT ». Technology transfer : fundamental principles and innovative technical solutions 4 (30 novembre 2020) : 25–28. http://dx.doi.org/10.21303/2585-6847.2020.001473.

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The article deals with the use of active or passive braking of a ship to stop it at a given point. To substantiate the relevance of the study, an analysis of the literature on the problem of ensuring the safe maneuvering of ships was carried out, in which the issues of theoretical and experimental studies of the turnability of ships, the adequacy of the existing models of turnability to the real process of turning the ship, as well as the development of a system of autopilot control of the ship's heading using the principles of fuzzy logic were considered. Considerable attention is paid to the development of an information system for simulating the movement of ships with complex dynamic models. The necessary analytical expressions are given that characterize the dependences of the time and the distance traveled to the stop of the ship on the mode of active and passive braking, which are required to solve the problem posed in the work. A formal description of the maneuver for stopping the ship at a given point by active and passive braking is obtained. This description makes it possible to determine the moment of engine stop in case of passive braking or the moment of its reverse – in case of active braking, provided that the ship is following a heading equal to the bearing to a given point. Cases of presence and absence of current in the area of ship maneuver are considered. In the case of the presence of a current, two stages of the ship's movement are considered: from the zero moment of time until the moment of the start of braking, when the speed of the ship is unchanged, and the second stage, from the moment of the start of braking until the stop of the ship, when the speed of the ship decreases. To take into account the flow during braking with an exit to a given point, two methods are proposed. The first one is at a constant flow angle with a lateral displacement relative to the programmed trajectory of motion. And the second – with a variable flow angle at zero displacement relative to it. A successful check of the correctness of the results obtained by simulation computer modeling of maneuvers for stopping the ship at a given point of braking, taking into account the current, has been carried out

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Zhileykin, M. M., et D. S. Chugunov. « Algorithm of anti-lock braking system for two-axle vehicles with one driving axle with adaptive redistribution of braking forces ». Izvestia MGTU MAMI 1, n^o 2 (2021) : 93–100. http://dx.doi.org/10.31992/2074-0530-2021-48-2-93-100.

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The main purpose of active vehicle safety systems is to prevent an emergency situation. If such a situation arises, the system independently (without the participation of the driver) assesses the prob-able danger and, if necessary, prevents it by actively intervening in the driving process. One of the ways to increase the active safety of vehicles when braking is the use of anti-lock braking systems (ABS). The main problems in ensuring the operation of the ABS, built on different control principles and with different control parameters, are the impossibility of directly determining the vehicle speed and, as a result, the slip coefficient, as well as the inability to effectively respond to changing road conditions during braking. For example, when braking on a slippery supporting surface and trying to avoid an obstacle in front, there is a risk of losing traction and skidding. The algorithms of the ABS operation developed at present do not ensure the prevention of the occurrence and development of skidding under the conditions indicated above. The aim of the work is to increase the stability and controllability of two-axle vehicles with one driving axle during braking due to the adaptive redistribution of braking forces on the wheels. An algorithm for the operation of an anti-lock braking system with adaptive redistribution of braking forces on the wheels of a vehicle is proposed. Thanks to this algorithm, when braking on a slippery surface of a two-axle vehicle with one driving axle, the absence of wheel blocking and also skid re-sistance are ensured. The efficiency and effectiveness of the proposed algorithm when braking a two-axle vehicle with one driving axle on a slippery supporting surface were proved by the methods of simulation.

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Wang, Fahui, Yongjie Lu et Haoyu Li. « Heavy-Duty Vehicle Braking Stability Control and HIL Verification for Improving Traffic Safety ». Journal of Advanced Transportation 2022 (13 juillet 2022) : 1–27. http://dx.doi.org/10.1155/2022/5680599.

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The braking failure of heavy vehicles under long downhill or curved conditions may cause traffic crash and reduce road traffic efficiency. Therefore, to improve the traffic safety and braking stability of vehicles under special road conditions, a braking dynamic model and control system based on the interval uncertainty analysis are proposed, and the safety of the active control model is verified by experiments (HIL). Firstly, the interval uncertain dynamic model is established based on the Monte Carlo method, and the braking failure simulation analysis of the right front wheel of heavy vehicles is carried out in the set of three uncertain intervals. Secondly, the fuzzy PID and sliding mode controller based on yaw and centroid error are designed to find the optimal control strategy from the two kinds of control strategies for HIL experiments. Finally, the actual control effect and feasibility of these control algorithms for heavy vehicle braking under special road conditions are verified by HIL experiments. The experimental results show that under the action of the fuzzy PID control strategy, the running stability of the vehicle is significantly improved compared with no control, which effectively reduces the risk of vehicle braking failure and improves the active safety and stability of the vehicle.

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Vilhu, Osmi. « On Active Stars, Coronal Loops, Magnetic Braking and All That ». Highlights of Astronomy 7 (1986) : 467–70. http://dx.doi.org/10.1017/s153929960000678x.

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McCann, Gregory, et Prashant Khapane. « Integration of Active Braking System in Multi-Body Systems Tool to Improve Prediction of Braking Loads ». SAE International Journal of Commercial Vehicles 10, n^o 1 (28 mars 2017) : 219–35. http://dx.doi.org/10.4271/2017-01-0418.

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Aghasizade, Sajjad, Mehdi Mirzaei et Sadra Rafatnia. « Novel constrained control of active suspension system integrated with anti-lock braking system based on 14-degree of freedom vehicle model ». Proceedings of the Institution of Mechanical Engineers, Part K : Journal of Multi-body Dynamics 232, n^o 4 (18 janvier 2018) : 501–20. http://dx.doi.org/10.1177/1464419317752612.

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This paper deals with a novel method for integration of the active suspension system and the anti-lock braking system. In the proposed method, a new nonlinear controller with state constraints is developed for the active suspension system based on the response prediction of 14-degree of freedom vehicle model. The proposed controller isolates the vehicle from road roughness in normal conditions and assists the anti-lock braking system by ensuring a good contact between the tyre and road during hard braking. In addition, the tyre deflection is limited to prevent the threat of tyre bursting. To develop the active suspension system controller, at first, a performance index consisting of a weighted combination of predicted responses of suspension system is expanded as a function of current control input. At the same time, the state constraints of tyre normal force and tyre deflection are transformed to the equivalent constraints of control input by the same prediction approach. Then, the control law is found by minimizing the expanded performance index in the presence of input constraints. The Karush–Kuhn–Tucker theorem is employed to solve the performed constrained optimization problem analytically. The performance of the proposed active suspension system controller integrated with the designed nonlinear anti-lock braking system controller is evaluated for a full vehicle model including roll and pitch motions during braking on irregular random roads. The results show that both the body acceleration and the vehicle stopping distance are decreased for the proposed integrated strategy compared with other conventional strategies.

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35

Schorn, Matthias, Jürgen Schmitt, Ulrich Stählin et Rolf Isermann. « MODEL BASED BRAKING CONTROL WITH SUPPORT BY ACTIVE STEERING ». IFAC Proceedings Volumes 38, n^o 1 (2005) : 216–21. http://dx.doi.org/10.3182/20050703-6-cz-1902.01246.

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Keller, Christoph G., Thao Dang, Hans Fritz, Armin Joos, Clemens Rabe et Dariu M. Gavrila. « Active Pedestrian Safety by Automatic Braking and Evasive Steering ». IEEE Transactions on Intelligent Transportation Systems 12, n^o 4 (décembre 2011) : 1292–304. http://dx.doi.org/10.1109/tits.2011.2158424.

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Tanelli, Mara, Matteo Corno, Ivo Boniolo et Sergio M. Savaresi. « Active braking control of two-wheeled vehicles on curves ». International Journal of Vehicle Autonomous Systems 7, n^o 3/4 (2009) : 243. http://dx.doi.org/10.1504/ijvas.2009.033263.

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Dmitrieva, Anna, Alexander Enaev, Vladimir Timofeev, Evgeny Seleznev et Tatyana Klets. « INFLUENCE OF VEHICLE SUSPENSION PARAMETERS ON ITS BRAKING PROPERTIES ». ENVIRONMENT. TECHNOLOGIES. RESOURCES. Proceedings of the International Scientific and Practical Conference 3 (16 juin 2021) : 58–61. http://dx.doi.org/10.17770/etr2021vol3.6593.

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The paper focuses on the study of the performance of elastic and damping parameters of the car suspension. The problem of arising vibrations of the sprung and unsprung vehicle masses on the braking process is considered. The article presents theoretical models of vehicle braking taking into account the oscillations of the vehicle's sprung masses. The research results will make it possible to establish the relationship between the suspension parameters and the estimated parameters of braking properties, to supplement the "driver - car - road" system, and also to more accurately assess the active safety of vehicles associated with braking dynamics.

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Skrúcaný, Tomáš, František Synák et Štefánia Semanová. « Influence of the Braking System that is Contrary to Legislation on Breaking Characteristics of Passenger Car ». Transport technic and technology 14, n^o 1 (1 juin 2018) : 1–5. http://dx.doi.org/10.2478/ttt-2018-0001.

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Abstract There are also the vehicles among the other vehicles in road traffic that have been modified without being authorised by their producer. These also include modifications such as structural modifications in the vehicle break system. Besides a brake system of road motor vehicles is one of the main factors influencing the active safety of vehicles. The design of the brake system, its technical condition and additional intervention in its construction may have a positive as well as negative impact on the braking distance length and the value of the mean braking deceleration achieved. The paper focuses on the influence of the brake disc diameter of the front axle on the achieved value of the mean braking deceleration and the braking distance length, while the braking system has been modified for several times without being approved by car manufacturer. The introductory part of the paper describes the braking distance sections and it also explains the term of mean braking deceleration. The following part of the paper deals with the measurement methodology, measuring equipment and the vehicle used during the measurements as well as procedures employed. The results obtained from the measurements are processed and presented in tables and also in graphs for greater clarity. The final part of the paper summarizes and evaluates the measured results. The importance of the paper lies in quantification of the influence of brake discs with different diameters on the vehicle active safety in the case of a particular vehicle.

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Li, Tao, Shuo Zhang, Gang Xiao, Minqi Wang, Hanwen Zhong et Jianghua Feng. « Brake Instability Dynamic Model and Active Control Strategy for a Multiunit Articulated Rubber-Wheel Autonomous Rail Rapid Transit System ». Sustainability 14, n^o 21 (4 novembre 2022) : 14531. http://dx.doi.org/10.3390/su142114531.

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Due to the particularity of the structure, the dynamic properties of multiunit articulated rubber-wheel autonomous rail rapid transit system are very complex, which increases the difficulty of studying its braking stability. In this paper, a dynamic analysis model for the emergency braking of a multiunit articulated rubber-wheel autonomous rail rapid transit system is established by introducing the axle load transfer, suspension deformation compatibility equation, articulation force relationship equations, etc. Based on an in-depth analysis of the risks of the lateral swing instability and their formation mechanisms, an active control strategy for the multiunit articulated rubber-wheel autonomous rail rapid transit system under emergency braking conditions is innovatively proposed to ensure the stability of the vehicle, with the shortest braking distance as the optimization goal. Through simulation and experimentation, the established dynamic model is confirmed to approach the real vehicle well, and the feasibility of the active control strategy is proved.

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Lie, Guo, Ren Zejian, Ge Pingshu et Chang Jing. « Advanced Emergency Braking Controller Design for Pedestrian Protection Oriented Automotive Collision Avoidance System ». Scientific World Journal 2014 (2014) : 1–11. http://dx.doi.org/10.1155/2014/218246.

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Automotive collision avoidance system, which aims to enhance the active safety of the vehicle, has become a hot research topic in recent years. However, most of the current systems ignore the active protection of pedestrian and other vulnerable groups in the transportation system. An advanced emergency braking control system is studied by taking into account the pedestrians and the vehicles. Three typical braking scenarios are defined and the safety situations are assessed by comparing the current distance between the host vehicle and the obstacle with the critical braking distance. To reflect the nonlinear time-varying characteristics and control effect of the longitudinal dynamics, the vehicle longitudinal dynamics model is established in CarSim. Then the braking controller with the structure of upper and lower layers is designed based on sliding mode control and the single neuron PID control when confronting deceleration or emergency braking conditions. Cosimulations utilizing CarSim and Simulink are finally carried out on a CarSim intelligent vehicle model to explore the effectiveness of the proposed controller. Results display that the designed controller has a good response in preventing colliding with the front vehicle or pedestrian.

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Begizhonov, Shakhrom, Polina Buyvol, Irina Makarova et Eduard Tsybunov. « Parameterization of the ABS electronic control unit for increasing the autonomous trucks’ active safety ». MATEC Web of Conferences 341 (2021) : 00026. http://dx.doi.org/10.1051/matecconf/202134100026.

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The article is devoted to the issue of improving the autonomous vehicles safety. The anti-lock braking system was chosen as the object of the study, since it is one of the components of the vehicle active safety during emergency braking. Its functioning varies depending on parameters such as vehicle type, transmission type, external and internal steering wheel angles. It is necessary to parameterize correctly the electronic control unit of the anti-lock braking system depending on the specific values of these parameters. For this, a software module was developed that reads the values of the vehicle parameters from a file and sends their array to the electronic control unit. Then we can check the result: how the block responded to the sent request -positively or negatively. All this will speed up the parameterization process, increase its accuracy, preventing the occurrence of operator errors during its implementation.

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Zulhilmi, I. M., M. H. Peeie, R. I. M. Eiman, I. M. Izhar et S. M. Asyraf. « Investigation on Vehicle Dynamic Behaviour During Emergency Braking at Different Speed ». International Journal of Automotive and Mechanical Engineering 16, n^o 1 (16 mars 2019) : 6161–72. http://dx.doi.org/10.15282/ijame.16.1.2019.6.0468.

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Safety system of the vehicle can be divided into two main categories; passive and active safety system. The purpose of the passive safety system is to protect the occupant during an accident, while active safety system allows the vehicle to be manoeuvred to avoid any collision. Although active safety system can prevent the accident, in a critical situation such as emergency braking, the dynamic behaviour of the vehicle changes abruptly, and the vehicle becomes unstable. The objective of this study is to analyse the dynamic behaviour of the vehicle during emergency braking with and without anti-lock braking system (ABS). In this study, the dynamic behaviour of the vehicle is observed by the simulation model that has been developed in the MATLAB-Simulink. The analysis vehicle model is Universiti Malaysia Pahang (UMP) test car, model Proton Persona. During braking, when ABS control unit detect the wheel is to lock-up, the hydraulic control unit closed the hydraulic valve to release the brake pad on the wheel. This allows the wheel to spin intermittently during braking. From the simulation results, when ABS is not applied to the vehicle, the front tires were lock-up and the vehicle become skidding. However, when ABS is applied, the speed of all tires decreased gradually and the vehicle is not skidding. The simulation results also show that the stopping distance with ABS is improved 28% compared without ABS.

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Yang, Jialin, Mengqi Li et Haitao Zhu. « Study & ; Improvement of Occupant Out-of-position Injuries Under Pre-crash Braking Condition ». Journal of Physics : Conference Series 2029, n^o 1 (1 septembre 2021) : 012138. http://dx.doi.org/10.1088/1742-6596/2029/1/012138.

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Abstract Although the impact strength can be reduced by AEB and other active safety technologies, the occupants may move forward under braking condition and reduce the protection space of the restraint system. The out-of-position displacement and injuries of occupants under braking conditions are studied by sled tests. The injury characteristics of the out-of-position occupant are obtained. By orthogonal tests, the influence of out-of-position on the injury of different body regions are analysed. MADYMO active human body simulation model is established, and the characteristics of the occupant forward displacement under different braking waveforms are studied by single variable method. By using the active seatbelt, the occupant’s forward displacement is restrained. With the use of Central Composite Design (CCD) method, the response surface model of the occupant’s neck displacement relative to the pretension force and pretension time of the active seatbelt is established. The effects of pretension force and pretension time on out-of-position displacement are studied, and the optimal design is carried out to obtain the parameter combination.

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Liu, Qi Jia, et Si Zhong Chen. « The Control of the Braking Stability of Active Rear Wheel Steering Vehicle Based on LQR ». Applied Mechanics and Materials 416-417 (septembre 2013) : 909–13. http://dx.doi.org/10.4028/www.scientific.net/amm.416-417.909.

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The aim of this article is to improve the brake stability of active rear wheel steering vehicle. The optimal theory of linear quadratic regulator is used to construct a controller, and the aim of the controller is to maintain the side slip angle is zero, and the control parameter is set according to the change of velocity when braking. An antilock brake model based on the door limit of wheel slip rate is constructed. The analysis is carried on a front wheel steering vehicle, which has two kinds of unti-lock mode. Meanwhile, an active rear wheel steering vehicle with two kinds of unti-lock mode is performed, also. All tests are performed on the bisectional road. The results of analysis show that the active rear wheel steering vehicle using the anti-lock mode of four wheels independent control can give the shortest braking distance, the smaller side slip angle and the smaller deviation from the lane. So it can give more contribution to the braking safety.

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46

Volkov, V. « MINIMIZATION OF ELECTRICAL CONSUMPTION OF A FREQUENCY-REGULATION INDUCTION MOTOR WITH A FAN LOAD IN START-BRAKING REGIMES ». Electromechanical and energy saving systems 4, n^o 56 (décembre 2021) : 8–24. http://dx.doi.org/10.30929/2072-2052.2021.4.56.8-24.

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Purpuse. To minimize the total power consumption in start-braking regimes by a three-phase squirrel-cage frequency-regulated induction motor, loaded a centrifugal fan (or smoke exhauster), and also to obtain analytical dependencies for calculating the optimal durations of acceleration and deceleration times, corresponding to minimizing the total energy consumption of this motor in start-braking regimes with the indicated type of load. Metodology. Based on the methods of calculus of variations and numerical solution of non-linear differential equations, the quasi-optimal type of trajectories of speed change (tachograms) of the motor with the considered load in start-braking regimes is determined. Using the methods of mathematical analysis and similarity, the acceleration and deceleration times of an induction motor with a fan load were optimized for different (linear, parabolic and quasi-optimal) types of tachograms. Using the method of computer simulation, the energy consumption in the start-braking regimes of an induction motor with the indicated load for these types of tachograms was quantified. Results. Refined analytical dependencies are obtained for calculating the consumed active power and energy in start-braking regimes by a frequency-regulated induction motor with a fan load for the mentioned various types of tachograms. Analytical optimization of the consumption of active energy of this motor in start-braking regimes has been carried out. The change at the optimal durations for the starting-braking regimes and the corresponding it’s total energy consumption of the motor with varying the maximum value of the motor speed in these regimes has been researched. A quantitative assessment of transient electromechanical and energy processes in the considered motor with a fan load has been carried out. For this motor, as applied to the non-regenerative version of the static frequency converter, a scalar automatic control system is proposed, by means of which the motor accelerates with a constant rotor flux linkage with a given (linear, parabolic or quasi-optimal) speed trajectory and brakes on freewheel. The expected annual saving of active energy by an induction motor, loaded with a smoke exhauster, in starting and braking regimes, achieved by optimizing the form of the tachograms and the duration of the acceleration and deceleration times, is determined. Originality. Analytical dependencies are obtained for calculating the optimal durations of the acceleration and deceleration times of an induction motor with a fan load, corresponding to minimizing the energy consumption of this motor in start-braking regimes. The "U"-shaped form of dependences of the total energy, consumed during acceleration (or the total generated energy during braking) of the induction motor in function the duration of the deceleration (or braking) times is established. An analytical dependence is obtained for changing the speed of a motor loaded by a fan or a smoke exhauster during the freewheel braking regime, and an analytical expression is proposed for determining the duration of the indicated braking time. Practical value. On the example of an induction motor loaded by a smoke exhauster, the possibility of saving the total energy consumption in start-braking regimes was identified: from 77 to 90 % – due to the use of the proposed quasi-optimal tachogram and the use of practically realizable optimal acceleration and deceleration times, and also in the amount of 10 % – through the transition from freewheel braking to regenerative braking. Figures 6, tables 6, references 22.

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Pyanzov, Sergey, Pavel Ionov, Aleksandr Zemskov et Aleksey Stolyarov. « MODELING THE TORQUE OF THE HYDRAULIC VOLUME DRIVE WITH THE PARAMETERS OF THE HYDRAULIC LOADING DEVICE ». Tekhnicheskiy servis mashin 1, n^o 142 (janvier 2021) : 72–82. http://dx.doi.org/10.22314/2618-8287-2020-59-1-72-82.

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Currently, manufacturers for a reliable assessment of the technical condition of volumetric hydraulic drives use the dynamic test method, which allows you to determine the torque (braking) moment on the shaft of the tested hydraulic motor. There are diffi culties in reliably determining the value of the developed torque (braking) moment. (Research purpose) The research purpose is in constructing a mathematical model of the relationship between the developed torque (braking) moment of a volumetric hydraulic drive and the parameters of a hydraulic loading device. (Materials and methods) The article presents a hydraulic loading device that provides the necessary braking torque on the shaft of the tested hydraulic motor. Authors conducted one-factor and multifactor experiments-dynamic tests of the new Sauer-Danfoss series 90 volumetric hydraulic drive using a hydraulic loading device. The torque (braking) was monitored using a non-contact digital torque sensor M 425 3-A datum electronics and a digital indicator with LCD display (Results and discussion) As a result of one-factor passive experiments, the factors infl uencing the optimization parameter and the ranges of their variation were determined. A mathematical model of the relationship between the developed torque (braking) moment of a volumetric hydraulic drive and the parameters of a hydraulic loading device was obtained by a multi-factor active experiment. The article presents a complete planning matrix for a multi-factor active experiment, which refl ects the sequence of all possible combinations of factors that affect the optimization parameter. The most signifi cant factors affecting the value of the developed torque (braking) moment were: the pressure drop and the temperature of the working fluid in the hydraulic lines of the hydraulic loading device. (Conclusions) The mathematical model allows us to determine with high accuracy the developed torque (braking) of the volumetric hydraulic drive.

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Pyanzov, Sergey V., Pavel A. Ionov, Aleksandr M. Zemskov et Aleksey V. Stolyarov. « MODELING THE TORQUE OF THE HYDRAULIC VOLUME DRIVE WITH THE PARAMETERS OF THE HYDRAULIC LOADING DEVICE ». Tekhnicheskiy servis mashin 1, n^o 142 (mars 2021) : 72–82. http://dx.doi.org/10.22314/2618-8287-2021-59-1-72-82.

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Currently, manufacturers for a reliable assessment of the technical condition of volumetric hydraulic drives use the dynamic test method, which allows you to determine the torque (braking) moment on the shaft of the tested hydraulic motor. There are difficulties in reliably determining the value of the developed torque (braking) moment. (Research purpose) The research purpose is in constructing a mathematical model of the relationship between the developed torque (braking) moment of a volumetric hydraulic drive and the parameters of a hydraulic loading device. (Materials and methods) The article presents a hydraulic loading device that provides the necessary braking torque on the shaft of the tested hydraulic motor. Authors conducted one-factor and multi- factor experiments-dynamic tests of the new Sauer-Danfoss series 90 volumetric hydraulic drive using a hydraulic loading device. The torque (braking) was monitored using a non-contact digital torque sensor M 425 3-A datum electronics and a digital indicator with LCD display (Results and discussion) As a result of one-factor passive experiments, the factors influencing the optimization parameter and the ranges of their variation were determined. A mathematical model of the relationship between the developed torque (braking) moment of a volumetric hydraulic drive and the parameters of a hydraulic loading device was obtained by a multi-factor active experiment. The article presents a complete planning matrix for a multi-factor active experiment, which reflects the sequence of all possible combinations of factors that affect the optimization parameter. The most significant factors affecting the value of the developed torque (braking) moment were: the pressure drop and the temperature of the working fluid in the hydraulic lines of the hydraulic loading device. (Conclusions) The mathematical model allows us to determine with high accuracy the developed torque (braking) of the volumetric hydraulic drive.

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Badea, Gabriel, Marius Toma, Dan Alexandru Micu, Gheorghe Frăţilă et Ştefan Saragea. « Modelling and simulation automatic braking systems for vehicles ». IOP Conference Series : Materials Science and Engineering 1235, n^o 1 (1 mars 2022) : 012033. http://dx.doi.org/10.1088/1757-899x/1235/1/012033.

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Abstract An automatic braking system is an important future step in attending the autonomous vehicle. This system increases the active safety of a vehicle, significantly reducing road accidents, and lowering the effects of accidents. The paper will present the steps that will develop the autonomous braking systems in conformity with the Society of Automotive Engineers (SAE) from the USA. As well the paper will present the modelling and simulating of the automatic braking systems of a vehicle from the middle class using LMS Amesim software.

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Shen, Chuanliang, Shan Zhang, Zhenhai Gao, Binyu Zhou, Wei Su et Hongyu Hu. « Study on a Right-Turning Intelligent Vehicle Collision Warning and Avoidance Algorithm Based on Monte Carlo Simulation ». Journal of Advanced Transportation 2020 (1 août 2020) : 1–11. http://dx.doi.org/10.1155/2020/9405760.

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With the development of intelligent vehicle technology, the demand for advanced driver assistant systems kept increasing. To improve the performance of the active safety systems, we focused on right-turning vehicle’s collision warning and avoidance. We put forward an algorithm based on Monte Carlo simulation to calculate the collision probability between the right-turning vehicle and another vehicle (or pedestrian) in intersections. We drew collision probability curves which used time-to-collision as the horizontal axis and collision probability as the vertical axis. We established a three-level collision warning system and used software to calculate and simulate the collision probability and warning process. To avoid the collision actively when turning right, a two-stage braking strategy is applied. Taking four right-turning collision conditions as examples, the two-stage braking strategy was applied, analysing and comparing the anteroposterior curve diagram simultaneously to avoid collision actively and reduce collision probability. By comparison, the collision probability 2 s before active collision avoidance was more than 80% and the collision probability may even reach 100% in certain conditions. To improve the active safety performance, the two-stage braking strategy can reduce the collision probability from exceeding 50% to approaching 0% in 2 s and reduce collision probability to less than 5% in 3 s. By changing four initial positions, the collision probability curve calculation algorithm and the two-stage braking strategy are validated and analysed. The results verified the rationality of the collision probability curve calculation algorithm and the two-stage braking strategy.

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