The Experts below are selected from a list of 84714 Experts worldwide ranked by ideXlab platform
Lee Alexander - One of the best experts on this subject based on the ideXlab platform.
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Estimation of Tire-Road Friction Coefficient Using a Novel Wireless Piezoelectric Tire Sensor
IEEE Sensors Journal, 2011Co-Authors: Gurkan Erdogan, Lee Alexander, Rajesh RajamaniAbstract:A tire-road Friction Coefficient estimation approach is proposed which makes use of the uncoupled lateral deflection profile of the tire carcass measured from inside the tire through the entire contact patch. The unique design of the developed wireless piezoelectric sensor enables the decoupling of the lateral carcass deformations from the radial and tangential deformations. The estimation of the tire-road Friction Coefficient depends on the estimation of slip angle, lateral tire force, aligning moment, and the use of a brush model. The tire slip angle is estimated as the slope of the lateral deflection curve at the leading edge of the contact patch. The portion of the deflection profile measured in the contact patch is assumed to be a superposition of three types of lateral carcass deformations, namely, shift, yaw, and bend. The force and moment acting on the tire are obtained by using the Coefficients of a parabolic function which approximates the deflection profile inside the contact patch and whose terms represent each type of deformation. The estimated force, moment, and slip angle variables are then plugged into the brush model to estimate the tire-road Friction Coefficient. A specially constructed tire test rig is used to experimentally evaluate the performance of the developed estimation approach and the tire sensor. Experimental results show that the developed sensor can provide good estimation of both slip angle and tire-road Friction Coefficient.
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measurement of uncoupled lateral carcass deflections with a wireless piezoelectric sensor and estimation of tire road Friction Coefficient
ASME 2010 Dynamic Systems and Control Conference DSCC2010, 2010Co-Authors: Gurkan Erdogan, Lee Alexander, Rajesh RajamaniAbstract:A new tire-road Friction Coefficient estimation approach based on lateral carcass deflection measurements is proposed. The unique design of the developed wireless piezoelectric sensor decouples lateral carcass deformations from radial and tangential carcass deformations. The estimation of the tire-road Friction Coefficient depends on the estimation of the slip angle and the lateral tire force. The tire slip angle is estimated as the slope of the lateral deflection curve at the leading edge of the contact patch. The lateral tire force is obtained by using a parabolic relationship with the lateral deflections in the contact patch. The estimated slip angle and lateral force are then plugged into a tire brush model to estimate the tire-road Friction Coefficient. A specially constructed tire test-rig is used to experimentally evaluate the performance of the tire sensor and the developed approach. Experimental results show that the proposed tire-road Friction Coefficient estimation approach is quite promising.Copyright © 2010 by ASME
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Friction Coefficient measurement for autonomous winter road maintenance
Vehicle System Dynamics, 2009Co-Authors: Gurkan Erdogan, Lee Alexander, Rajesh RajamaniAbstract:Real-time measurement of tyre-road Friction Coefficient is extremely valuable for winter road maintenance operations, since knowledge of tyre-road Friction Coefficient can be used to optimise application of deicing chemicals to the roadway. In this paper, a wheel-based tyre-road Friction Coefficient measurement system is developed for snowploughs. Unlike a traditional Norse meter, this system is based on measurement of lateral tyre forces, has minimal moving parts and does not use a brake actuator. Hence, it is reliable and inexpensive. A key challenge is quickly detecting changes in the estimated tyre-road Friction Coefficient while rejecting the high levels of vibratory noise in the measured force signal. Novel filtering and signal processing algorithms are developed to address this challenge, including a biased quadratic mean filter and an accelerometer-based vibration removal filter. Detailed experimental results are presented on the performance of the Friction estimation system on different types of road surfaces. It is also shown that disturbances due to lateral and longitudinal vehicle manoeuvres on the estimated Friction Coefficient can be removed by using accelerometer-based filtering.
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Friction Coefficient measurement system for winter maintenance vehicles
American Control Conference, 2008Co-Authors: Gurkan Erdogan, Lee Alexander, Rajesh RajamaniAbstract:Real-time measurement of tire-road Friction Coefficient is extremely valuable for winter road maintenance operations. In winter maintenance, knowledge of tire-road Friction Coefficient can be used to optimize application of deicing and anti-icing chemicals to the roadway. In this paper, a wheel based tire-road Friction Coefficient measurement system is developed for snowplows. Unlike a traditional Norse meter, this system is based on measurement of lateral tire forces, has minimal moving parts and does not use any actuators. Hence, it is reliable and inexpensive. A key challenge is quickly detecting changes in estimated tire-road Friction Coefficient while rejecting the high levels of noise in measured force signals. Novel filtering and signal processing algorithms are developed to address this challenge including a biased quadratic mean filter and an accelerometer based vibration removal filter. Detailed experimental results are presented on the performance of the Friction estimation system on different types of road surfaces. Experimental results show that the biased quadratic mean filter works very effectively to eliminate the influence of noise and quickly estimate changes in Friction Coefficient. Further, the use of accelerometers and an intelligent algorithm enables elimination of the influence of driver steering maneuvers, thus providing a robust Friction measurement system under all operating conditions.
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gps based real time tire road Friction Coefficient identification
2004Co-Authors: Junmin Wang, Lee Alexander, Rajesh RajamaniAbstract:This project concentrates on the development of real- time tire-road Friction Coefficient estimation systems for snowplows that can reliably estimate different road surface Friction levels and quickly detect abrupt changes in Friction Coefficient. Two types of systems are developed - a vehicle-based system and a wheel-based system. The vehicle-based Friction measurement system utilizes vehicle motion measurements from differential global positioning system (GPS) and other on-board vehicle sensors. The wheel-based Friction measurement system utilizes a redundant wheel that is mounted at a small angle to the longitudinal axis of the vehicle. Complete technical details on the vehicle-based Friction measurement system are presented in this report. Compared to previously published results in literature, the advantage of the vehicle-based system developed here is that it is applicable during both vehicle acceleration and braking and works reliably for a wide range of slip ratios, including high slip conditions. The system can be used on front/rear-wheel drive as well as all-wheel drive vehicles. Extensive results are presented from experimental results conducted on various surfaces with a winter maintenance vehicle called the Safeplow. The experimental results show that the system performs reliably and quickly in estimating Friction Coefficient on different road surfaces during various vehicle maneuvers.
Rajesh Rajamani - One of the best experts on this subject based on the ideXlab platform.
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Estimation of Tire-Road Friction Coefficient Using a Novel Wireless Piezoelectric Tire Sensor
IEEE Sensors Journal, 2011Co-Authors: Gurkan Erdogan, Lee Alexander, Rajesh RajamaniAbstract:A tire-road Friction Coefficient estimation approach is proposed which makes use of the uncoupled lateral deflection profile of the tire carcass measured from inside the tire through the entire contact patch. The unique design of the developed wireless piezoelectric sensor enables the decoupling of the lateral carcass deformations from the radial and tangential deformations. The estimation of the tire-road Friction Coefficient depends on the estimation of slip angle, lateral tire force, aligning moment, and the use of a brush model. The tire slip angle is estimated as the slope of the lateral deflection curve at the leading edge of the contact patch. The portion of the deflection profile measured in the contact patch is assumed to be a superposition of three types of lateral carcass deformations, namely, shift, yaw, and bend. The force and moment acting on the tire are obtained by using the Coefficients of a parabolic function which approximates the deflection profile inside the contact patch and whose terms represent each type of deformation. The estimated force, moment, and slip angle variables are then plugged into the brush model to estimate the tire-road Friction Coefficient. A specially constructed tire test rig is used to experimentally evaluate the performance of the developed estimation approach and the tire sensor. Experimental results show that the developed sensor can provide good estimation of both slip angle and tire-road Friction Coefficient.
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measurement of uncoupled lateral carcass deflections with a wireless piezoelectric sensor and estimation of tire road Friction Coefficient
ASME 2010 Dynamic Systems and Control Conference DSCC2010, 2010Co-Authors: Gurkan Erdogan, Lee Alexander, Rajesh RajamaniAbstract:A new tire-road Friction Coefficient estimation approach based on lateral carcass deflection measurements is proposed. The unique design of the developed wireless piezoelectric sensor decouples lateral carcass deformations from radial and tangential carcass deformations. The estimation of the tire-road Friction Coefficient depends on the estimation of the slip angle and the lateral tire force. The tire slip angle is estimated as the slope of the lateral deflection curve at the leading edge of the contact patch. The lateral tire force is obtained by using a parabolic relationship with the lateral deflections in the contact patch. The estimated slip angle and lateral force are then plugged into a tire brush model to estimate the tire-road Friction Coefficient. A specially constructed tire test-rig is used to experimentally evaluate the performance of the tire sensor and the developed approach. Experimental results show that the proposed tire-road Friction Coefficient estimation approach is quite promising.Copyright © 2010 by ASME
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Friction Coefficient measurement for autonomous winter road maintenance
Vehicle System Dynamics, 2009Co-Authors: Gurkan Erdogan, Lee Alexander, Rajesh RajamaniAbstract:Real-time measurement of tyre-road Friction Coefficient is extremely valuable for winter road maintenance operations, since knowledge of tyre-road Friction Coefficient can be used to optimise application of deicing chemicals to the roadway. In this paper, a wheel-based tyre-road Friction Coefficient measurement system is developed for snowploughs. Unlike a traditional Norse meter, this system is based on measurement of lateral tyre forces, has minimal moving parts and does not use a brake actuator. Hence, it is reliable and inexpensive. A key challenge is quickly detecting changes in the estimated tyre-road Friction Coefficient while rejecting the high levels of vibratory noise in the measured force signal. Novel filtering and signal processing algorithms are developed to address this challenge, including a biased quadratic mean filter and an accelerometer-based vibration removal filter. Detailed experimental results are presented on the performance of the Friction estimation system on different types of road surfaces. It is also shown that disturbances due to lateral and longitudinal vehicle manoeuvres on the estimated Friction Coefficient can be removed by using accelerometer-based filtering.
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Friction Coefficient measurement system for winter maintenance vehicles
American Control Conference, 2008Co-Authors: Gurkan Erdogan, Lee Alexander, Rajesh RajamaniAbstract:Real-time measurement of tire-road Friction Coefficient is extremely valuable for winter road maintenance operations. In winter maintenance, knowledge of tire-road Friction Coefficient can be used to optimize application of deicing and anti-icing chemicals to the roadway. In this paper, a wheel based tire-road Friction Coefficient measurement system is developed for snowplows. Unlike a traditional Norse meter, this system is based on measurement of lateral tire forces, has minimal moving parts and does not use any actuators. Hence, it is reliable and inexpensive. A key challenge is quickly detecting changes in estimated tire-road Friction Coefficient while rejecting the high levels of noise in measured force signals. Novel filtering and signal processing algorithms are developed to address this challenge including a biased quadratic mean filter and an accelerometer based vibration removal filter. Detailed experimental results are presented on the performance of the Friction estimation system on different types of road surfaces. Experimental results show that the biased quadratic mean filter works very effectively to eliminate the influence of noise and quickly estimate changes in Friction Coefficient. Further, the use of accelerometers and an intelligent algorithm enables elimination of the influence of driver steering maneuvers, thus providing a robust Friction measurement system under all operating conditions.
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gps based real time tire road Friction Coefficient identification
2004Co-Authors: Junmin Wang, Lee Alexander, Rajesh RajamaniAbstract:This project concentrates on the development of real- time tire-road Friction Coefficient estimation systems for snowplows that can reliably estimate different road surface Friction levels and quickly detect abrupt changes in Friction Coefficient. Two types of systems are developed - a vehicle-based system and a wheel-based system. The vehicle-based Friction measurement system utilizes vehicle motion measurements from differential global positioning system (GPS) and other on-board vehicle sensors. The wheel-based Friction measurement system utilizes a redundant wheel that is mounted at a small angle to the longitudinal axis of the vehicle. Complete technical details on the vehicle-based Friction measurement system are presented in this report. Compared to previously published results in literature, the advantage of the vehicle-based system developed here is that it is applicable during both vehicle acceleration and braking and works reliably for a wide range of slip ratios, including high slip conditions. The system can be used on front/rear-wheel drive as well as all-wheel drive vehicles. Extensive results are presented from experimental results conducted on various surfaces with a winter maintenance vehicle called the Safeplow. The experimental results show that the system performs reliably and quickly in estimating Friction Coefficient on different road surfaces during various vehicle maneuvers.
Seibum B. Choi - One of the best experts on this subject based on the ideXlab platform.
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early detection of tire road Friction Coefficient based on pneumatic trail stiffness
Advances in Computing and Communications, 2016Co-Authors: Kyoungseok Han, Eunjae Lee, Seibum B. ChoiAbstract:This paper presents a method for estimating the maximum lateral tire-road Friction Coefficient and wheel side slip angle based on the pneumatic trail information that exhibits unique characteristics according to the road surface conditions. The high sensitivity of the pneumatic trail for the wheel side slip angle enables the proposed observer to detect the peak tire-road Friction Coefficient in low slip regions. The conventional method that is highly dependent on the tire model has drawbacks due to model uncertainty. In order to overcome these shortcomings, the proposed method minimizes the use of existing tire models. In addition, traction force is also considered in this paper using a correction factor. The estimation results are obtained recursively under the persistent excitation condition. A simulation is conducted first in order to verify the performance of the proposed method using a combination of the Carsim and Matlab & Simulink. Then, vehicle experiments are conducted on a proving ground in order to verify the feasibility of the proposed method. The verification results reveal that the early detection of the maximum tire-road Friction Coefficient is possible with less excitation signals than the conventional methods.
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Robust estimation of maximum tire-road Friction Coefficient considering road surface irregularity
International Journal of Automotive Technology, 2016Co-Authors: Y. Hwang, Seibum B. ChoiAbstract:An accurate estimation of the maximum tire-road Friction Coefficient may provide higher performance in a vehicle active safety control system. Unfortunately, real-time tire-road Friction Coefficient estimation is costly and necessitates additional sensors that must be installed and maintained at all times. This paper proposes an advanced longitudinal tire-road Friction Coefficient estimation method that is capable of considering irregular road surfaces. The proposed algorithm uses a stiffness based estimation method, however, unlike previous studies, improvements were made by suggesting a third order model to solve problems related to nonlinear mu-slip curve. To attain the tire-road Friction Coefficient, real-time normalized force is obtained from the force estimator as exerted from the tire in the low slip region using the recursive least squares method. The decisive aspect of using the suggested algorithm lies in its low cost and versatility. It can be used under irregular road conditions due to its capability of easily obtaining wheel speed and acceleration values from production cars. The newly improved algorithm has been verified to computer simulations as well as compact size cars on dry asphalt conditions.
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linearized recursive least squares methods for real time identification of tire road Friction Coefficient
IEEE Transactions on Vehicular Technology, 2013Co-Authors: Mooryong Choi, Jiwon Oh, Seibum B. ChoiAbstract:The tire-road Friction Coefficient is critical information for conventional vehicle safety control systems. Most previous studies on tire-road Friction estimation have only considered either longitudinal or lateral vehicle dynamics, which tends to cause significant underestimation of the actual tire-road Friction Coefficient. In this paper, the parameters, including the tire-road Friction Coefficient, of the combined longitudinal and lateral brushed tire model are identified by linearized recursive least squares (LRLS) methods, which efficiently utilize measurements related to both vehicle lateral and longitudinal dynamics in real time. The simulation study indicates that by using the estimated vehicle states and the tire forces of the four wheels, the suggested algorithm not only quickly identifies the tire-road Friction Coefficient with great accuracy and robustness before tires reach their Frictional limits but successfully estimates the two different tire-road Friction Coefficients of the two sides of a vehicle on a split- μ surface as well. The developed algorithm was verified through vehicle dynamics software Carsim and MATLAB/Simulink.
Kyongsu Yi - One of the best experts on this subject based on the ideXlab platform.
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real time slip based estimation of maximum tire road Friction Coefficient
IEEE-ASME Transactions on Mechatronics, 2004Co-Authors: Karl Hedrick, Kyongsu YiAbstract: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.
Jin-oh Hahn - One of the best experts on this subject based on the ideXlab platform.
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IMECE2002-32157 GPS-BASED REAL-TIME IDENTIFICATION OF TIRE-ROAD Friction Coefficient
2020Co-Authors: Jin-oh Hahn, R Rajamani, L AlexanderAbstract:ABSTRACT Vehicle control systems such as collision avoidance, adaptive cruise control and automated lane-keeping systems as well as ABS and stability control systems can benefit significantly from being made "road-adaptive". The estimation of tire-road Friction Coefficient at the wheels allows the control algorithm in such systems to adapt to external driving conditions. This paper develops a new tire-road Friction Coefficient estimation algorithm based on measurements related to the lateral dynamics of the vehicle. A lateral tire force model parameterized as a function of slip angle, Friction Coefficient, normal force and cornering stiffness is used. A real-time parameter identification algorithm that utilizes measurements from a differential GPS system and a gyroscope is used to identify the tire-road Friction Coefficient and cornering stiffness parameters of the tire. The advantage of the developed algorithm is that it does not require large longitudinal slip in order to provide reliable Friction estimates. Simulation studies indicate that a parameter convergence rate of one second can be obtained. Experiments conducted on both dry and slippery road indicate that the algorithm can work very effectively in identifying a slippery road. Two other new approaches to realtime tire road Friction identification system are also discussed in the paper
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gps based real time identification of tire road Friction Coefficient
IEEE Transactions on Control Systems and Technology, 2002Co-Authors: Jin-oh Hahn, Rajesh Rajamani, Lee AlexanderAbstract:Vehicle control systems such as collision avoidance, adaptive cruise control, and automated lane-keeping systems as well as ABS and stability control systems can benefit significantly from being made "road-adaptive." The estimation of tire-road Friction Coefficient at the wheels allows the control algorithm in such systems to adapt to external driving conditions. This paper develops a new tire-road Friction Coefficient estimation algorithm based on measurements related to the lateral dynamics of the vehicle. A lateral tire force model parameterized as a function of slip angle, Friction Coefficient, normal force and cornering stiffness is used. A real-time parameter identification algorithm that utilizes measurements from a differential global positioning system (DGPS) system and a gyroscope is used to identify the tire-road Friction Coefficient and cornering stiffness parameters of the tire. The advantage of the developed algorithm is that it does not require large longitudinal slip in order to provide reliable Friction estimates. Simulation studies indicate that a parameter convergence rate of 1 s can be obtained. Experiments conducted on both dry and slippery road indicate that the algorithm can work very effectively in identifying a slippery road.
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gps based real time identification of tire road Friction Coefficient
ASME 2002 International Mechanical Engineering Congress and Exposition, 2002Co-Authors: Jin-oh Hahn, Rajesh Rajamani, Lee AlexanderAbstract:Vehicle control systems such as collision avoidance, adaptive cruise control and automated lane-keeping systems as well as ABS and stability control systems can benefit significantly from being made “road-adaptive”. The estimation of tire-road Friction Coefficient at the wheels allows the control algorithm in such systems to adapt to external driving conditions. This paper develops a new tire-road Friction Coefficient estimation algorithm based on measurements related to the lateral dynamics of the vehicle. A lateral tire force model parameterized as a function of slip angle, Friction Coefficient, normal force and cornering stiffness is used. A real-time parameter identification algorithm that utilizes measurements from a differential GPS system and a gyroscope is used to identify the tire-road Friction Coefficient and cornering stiffness parameters of the tire. The advantage of the developed algorithm is that it does not require large longitudinal slip in order to provide reliable Friction estimates. Simulation studies indicate that a parameter convergence rate of one second can be obtained. Experiments conducted on both dry and slippery road indicate that the algorithm can work very effectively in identifying a slippery road. Two other new approaches to real-time tire road Friction identification system are also discussed in the paper.Copyright © 2002 by ASME
