The Experts below are selected from a list of 7797 Experts worldwide ranked by ideXlab platform

Ali Cinar - One of the best experts on this subject based on the ideXlab platform.

  • Dynamical investigation of effects of variable damper settings induced Brake Pressure oscillations on axle and wheel oscillations during ABS-braking based on experimental study
    Meccanica, 2013
    Co-Authors: Hakan Köylü, Ali Cinar
    Abstract:

    In this study, the effects of variable damping setting induced Brake Pressure oscillations on axle and wheel oscillations have been experimentally explored. For this, antilock Brake system (ABS) tests are conducted on wet and slippery rough roads with hard, medium-hard and soft shock absorbers. In ABS tests, the axle height, the longitudinal and vertical axle accelerations have been measured. The results are discussed for time and frequency responses of axle vibrations in vertical and longitudinal direction. The time responses are separately considered for high and low piston velocities of damper. Also, in order to occur the effects of changes in ABS-Brake Pressure on axle vibrations, novel rules are designed. These rules are based on the integration of suspension dynamics into braking dynamics. The results show that the Brake Pressure is distinctly changed by variable damping settings. In time responses, these differences are determined by changes in time period and magnitude of Brake Pressure during build-up and reduction process. In frequency responses, the Brake Pressure differences are occurred by the different change frequencies of Brake Pressure causing resonance at axle vibrations. Also, the changes in magnitude of resonance peaks have determined the effects of Brake Pressure changes on axle vibrations. As a result, it is possible to damp the oscillations by changing the magnitude and frequency of Brake Pressure by means of the damper settings during ABS-braking.

  • An Experimental Study on Impact of Hard Damper Setting on ABS-Braking Performance Through Brake Pressure Changes Under Rough Road Conditions#
    Mechanics Based Design of Structures and Machines, 2013
    Co-Authors: Hakan Köylü, Ali Cinar
    Abstract:

    In this study, the effects of hard damper setting on ABS braking performance have been experimentally investigated by taking Brake Pressure changes as a reference. For this aim, ABS tests have been conducted under wet and slippery rough road conditions by using medium-hard and hard dampers. In order to assess the test results, three braking maneuvers are considered. Test results show that hard damper setting improves ABS-braking performance under slippery road condition, while it deteriorates with wet road condition because of Brake Pressure oscillations occurring in vehicle body, axle and Brake Pressure pumping resonances. For this reason, the hard setting causes the bad braking performance during transition from slippery to wet road conditions.

  • Experimental design of control strategy based on Brake Pressure changes on wet and slippery surfaces of rough road for variable damper setting during braking with activated anti-lock Brake system
    Proceedings of the Institution of Mechanical Engineers Part D: Journal of Automobile Engineering, 2012
    Co-Authors: Hakan Köylü, Ali Cinar
    Abstract:

    In this study, the control strategy based on experimental study is established for a variable damper setting with activated anti-lock Brake system. For this, anti-lock Brake system braking tests have been conducted by using hard, medium-hard and soft dampers on a rough road which has wet and slippery surfaces. In anti-lock Brake system tests, Brake Pressure has been measured. The Brake Pressure increasing and decreasing rates have been obtained using measured Brake Pressure. The control strategy has been designed by using threshold values acquired from these test results related to Brake Pressure. For this, firstly, the Brake Pressure change thresholds of damper providing the shortest braking distance are determined. Then, the damping capacity stage rules are designed by depending on the Brake Pressure thresholds corresponding to the road conditions. The control strategy performance has been evaluated during transitions between wet and slippery roads. The results show that this control strategy is effectively applied to passenger cars without any change in electronic control unit configuration of anti-lock Brake system. For this control strategy, it is considerably important that the damper setting to provide the shortest braking distance is detected. Language: en

  • The influences of worn shock absorber on ABS braking performance on rough road
    International Journal of Vehicle Design, 2011
    Co-Authors: Hakan Köylü, Ali Cinar
    Abstract:

    In this study, the influence of the deteriorations occurring in damping capacity of the shock absorber on the braking performance of Anti-Lock Brake System (ABS) was experimentally investigated. For this, ABS tests were conducted on the rough road, which has ?-split and slippery surface by using worn and new shock absorbers. The results show that when ABS is activated, the Brake Pressure fluctuations are affected by the changes in shock absorber damping capacity. Accordingly, it is determined that the braking performance is deteriorated by both road surfaces with worn shock absorbers. The ?-split rough road condition with new shock absorber improves braking performance, whereas the slippery road condition makes this braking performance much worse.

A Simon - One of the best experts on this subject based on the ideXlab platform.

  • a novel electrohydraulic Brake system with tire road friction estimation and continuous Brake Pressure control
    IEEE Transactions on Industrial Electronics, 2016
    Co-Authors: Juan J Castillo, J A Cabrera, Antonio J Guerra, A Simon
    Abstract:

    The braking system is the main active safety equipment of vehicles. This paper presents a new Brake system architecture based on the use of proportional servovalves. The use of servovalves allows for faster and more precise control of the Pressure, preventing the wheels from locking and reducing braking distances. A new control block has been developed to determine the optimum Pressure in the braking circuit. The new controller is based on the use of fuzzy logic techniques. A Kalman-filter-based estimation algorithm allows for obtaining the adhesion between the wheel and road surface and vehicle speed. These parameters are used in a fuzzy block to detect the road type. Using the road type, an artificial neural network gives an estimation of the slip that produces higher adhesion, and a final block, which is also based on fuzzy logic, determines the optimal Pressure in the braking circuit. The performance of the new Brake architecture and controller is evaluated by simulating driving on different road surfaces and with real tests on dry and wet asphalt.

Kyongsu Yi - One of the best experts on this subject based on the ideXlab platform.

  • real time slip based estimation of maximum tire road friction coefficient
    IEEE-ASME Transactions on Mechatronics, 2004
    Co-Authors: Karl Hedrick, Kyongsu Yi
    Abstract:

    This paper presents a real-time maximum tire-road friction coefficient estimation method and field test results. The estimator is based on the relationship between the wheel slip ratio and the friction coefficient. An effective tire radius observer and a tire normal force observer have been designed for the computation of the slip ratio from wheel speed and vehicle speed measurements. The effective tire radius observer has been used so that the proposed method works for all driving situations. A tractive force estimator, a Brake gain estimator, and a normal force observer have been used for the estimation of the friction coefficient. The proposed estimation method for the maximum tire-road friction coefficient has been implemented using a fifth wheel and typical vehicle sensors such as engine speed, carrier speed, throttle position, and Brake Pressure sensors.

Hakan Köylü - One of the best experts on this subject based on the ideXlab platform.

  • Dynamical investigation of effects of variable damper settings induced Brake Pressure oscillations on axle and wheel oscillations during ABS-braking based on experimental study
    Meccanica, 2013
    Co-Authors: Hakan Köylü, Ali Cinar
    Abstract:

    In this study, the effects of variable damping setting induced Brake Pressure oscillations on axle and wheel oscillations have been experimentally explored. For this, antilock Brake system (ABS) tests are conducted on wet and slippery rough roads with hard, medium-hard and soft shock absorbers. In ABS tests, the axle height, the longitudinal and vertical axle accelerations have been measured. The results are discussed for time and frequency responses of axle vibrations in vertical and longitudinal direction. The time responses are separately considered for high and low piston velocities of damper. Also, in order to occur the effects of changes in ABS-Brake Pressure on axle vibrations, novel rules are designed. These rules are based on the integration of suspension dynamics into braking dynamics. The results show that the Brake Pressure is distinctly changed by variable damping settings. In time responses, these differences are determined by changes in time period and magnitude of Brake Pressure during build-up and reduction process. In frequency responses, the Brake Pressure differences are occurred by the different change frequencies of Brake Pressure causing resonance at axle vibrations. Also, the changes in magnitude of resonance peaks have determined the effects of Brake Pressure changes on axle vibrations. As a result, it is possible to damp the oscillations by changing the magnitude and frequency of Brake Pressure by means of the damper settings during ABS-braking.

  • An Experimental Study on Impact of Hard Damper Setting on ABS-Braking Performance Through Brake Pressure Changes Under Rough Road Conditions#
    Mechanics Based Design of Structures and Machines, 2013
    Co-Authors: Hakan Köylü, Ali Cinar
    Abstract:

    In this study, the effects of hard damper setting on ABS braking performance have been experimentally investigated by taking Brake Pressure changes as a reference. For this aim, ABS tests have been conducted under wet and slippery rough road conditions by using medium-hard and hard dampers. In order to assess the test results, three braking maneuvers are considered. Test results show that hard damper setting improves ABS-braking performance under slippery road condition, while it deteriorates with wet road condition because of Brake Pressure oscillations occurring in vehicle body, axle and Brake Pressure pumping resonances. For this reason, the hard setting causes the bad braking performance during transition from slippery to wet road conditions.

  • Experimental design of control strategy based on Brake Pressure changes on wet and slippery surfaces of rough road for variable damper setting during braking with activated anti-lock Brake system
    Proceedings of the Institution of Mechanical Engineers Part D: Journal of Automobile Engineering, 2012
    Co-Authors: Hakan Köylü, Ali Cinar
    Abstract:

    In this study, the control strategy based on experimental study is established for a variable damper setting with activated anti-lock Brake system. For this, anti-lock Brake system braking tests have been conducted by using hard, medium-hard and soft dampers on a rough road which has wet and slippery surfaces. In anti-lock Brake system tests, Brake Pressure has been measured. The Brake Pressure increasing and decreasing rates have been obtained using measured Brake Pressure. The control strategy has been designed by using threshold values acquired from these test results related to Brake Pressure. For this, firstly, the Brake Pressure change thresholds of damper providing the shortest braking distance are determined. Then, the damping capacity stage rules are designed by depending on the Brake Pressure thresholds corresponding to the road conditions. The control strategy performance has been evaluated during transitions between wet and slippery roads. The results show that this control strategy is effectively applied to passenger cars without any change in electronic control unit configuration of anti-lock Brake system. For this control strategy, it is considerably important that the damper setting to provide the shortest braking distance is detected. Language: en

  • The influences of worn shock absorber on ABS braking performance on rough road
    International Journal of Vehicle Design, 2011
    Co-Authors: Hakan Köylü, Ali Cinar
    Abstract:

    In this study, the influence of the deteriorations occurring in damping capacity of the shock absorber on the braking performance of Anti-Lock Brake System (ABS) was experimentally investigated. For this, ABS tests were conducted on the rough road, which has ?-split and slippery surface by using worn and new shock absorbers. The results show that when ABS is activated, the Brake Pressure fluctuations are affected by the changes in shock absorber damping capacity. Accordingly, it is determined that the braking performance is deteriorated by both road surfaces with worn shock absorbers. The ?-split rough road condition with new shock absorber improves braking performance, whereas the slippery road condition makes this braking performance much worse.

Yang Xing - One of the best experts on this subject based on the ideXlab platform.

  • Dynamic State Estimation for the Advanced Brake System of Electric Vehicles by Using Deep Recurrent Neural Networks
    IEEE Transactions on Industrial Electronics, 2020
    Co-Authors: Yang Xing
    Abstract:

    Dynamic state estimation is of considerable importance to the system monitoring, advanced control, and energy management of electrified vehicles (EVs). Among the dynamic states of various vehicle systems, the Brake Pressure is a key state that reflects the braking intent and maneuver of a driver and is highly correlated with the safety and energy performance of an EV. Thus, it is worth formulating a high-precision estimation algorithm for the Brake Pressure to better identify the braking intent of a driver and further enhance the multiperformance of the EVs. In this article, an integrated time-series model (TSM) based on multivariate deep recurrent neural networks (RNN) with long short-term memory (LSTM) units is developed for the dynamic estimation of the Brake Pressure of EVs. The naturalistic driving data are collected using a real electric vehicle under standard driving cycle scenarios. The signals of the vehicle and system states are measured using the controller area network (CAN) bus and preprocessed for model training and prediction. Next, a real-time multivariate LSTM-RNN model for Brake Pressure estimation is constructed based on the integrated speed estimation model. The real-time scheme iteratively estimates the future velocity and integrates this signal with other vehicle states to estimate a precise value of the braking Pressure. The proposed integrated TSM approach is compared with several existing baseline methods to demonstrate the advantage of the method. The testing results indicate that the proposed integrated TSM method can achieve a more reliable multistep prediction with a higher accuracy compared to that of the other methods, which demonstrates the feasibility and effectiveness of the proposed approach.

  • levenberg marquardt backpropagation training of multilayer neural networks for state estimation of a safety critical cyber physical system
    IEEE Transactions on Industrial Informatics, 2018
    Co-Authors: Yang Xing, Dongpu Cao, Junzhi Zhang, Teng Liu, Feiyue Wang
    Abstract:

    As an important safety-critical cyber-physical system (CPS), the braking system is essential to the safe operation of the electric vehicle. Accurate estimation of the Brake Pressure is of great importance for automotive CPS design and control. In this paper, a novel probabilistic estimation method of Brake Pressure is developed for electrified vehicles based on multilayer artificial neural networks (ANNs) with Levenberg–Marquardt backpropagation (LMBP) training algorithm. First, the high-level architecture of the proposed multilayer ANN for Brake Pressure estimation is illustrated. Then, the standard backpropagation (BP) algorithm used for training of the feed-forward neural network (FFNN) is introduced. Based on the basic concept of BP, a more efficient training algorithm of LMBP method is proposed. Next, real vehicle testing is carried out on a chassis dynamometer under standard driving cycles. Experimental data of the vehicle and the powertrain systems are collected, and feature vectors for FFNN training collection are selected. Finally, the developed multilayer ANN is trained using the measured vehicle data, and the performance of the Brake Pressure estimation is evaluated and compared with other available learning methods. Experimental results validate the feasibility and accuracy of the proposed ANN-based method for braking Pressure estimation under real deceleration scenarios.

  • Levenberg–Marquardt Backpropagation Training of Multilayer Neural Networks for State Estimation of a Safety-Critical Cyber-Physical System
    IEEE Transactions on Industrial Informatics, 2018
    Co-Authors: Yang Xing, Dongpu Cao, Junzhi Zhang, Teng Liu, Feiyue Wang
    Abstract:

    As an important safety-critical cyber-physical system (CPS), the braking system is essential to the safe operation of the electric vehicle. Accurate estimation of the Brake Pressure is of great importance for automotive CPS design and control. In this paper, a novel probabilistic estimation method of Brake Pressure is developed for electrified vehicles based on multilayer artificial neural networks (ANNs) with Levenberg–Marquardt backpropagation (LMBP) training algorithm. First, the high-level architecture of the proposed multilayer ANN for Brake Pressure estimation is illustrated. Then, the standard backpropagation (BP) algorithm used for training of the feed-forward neural network (FFNN) is introduced. Based on the basic concept of BP, a more efficient training algorithm of LMBP method is proposed. Next, real vehicle testing is carried out on a chassis dynamometer under standard driving cycles. Experimental data of the vehicle and the powertrain systems are collected, and feature vectors for FFNN training collection are selected. Finally, the developed multilayer ANN is trained using the measured vehicle data, and the performance of the Brake Pressure estimation is evaluated and compared with other available learning methods. Experimental results validate the feasibility and accuracy of the proposed ANN-based method for braking Pressure estimation under real deceleration scenarios.