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Viewing 31 to 60 of 10886
2017-03-28
Technical Paper
2017-01-0414
Bin Li, Xiaobo Yang, James Yang, Yunqing Zhang, Zeyu Ma
In this paper, a detailed 3D tire model is first proposed which includes a rigid rim with thickness, different layers of discretized belt points and a number of tread blocks attached on the area formatted by the neighboring belt points. The parameters of the proposed 3D tire model can be divided into two parts: the stiffness and damping values which only involve the in-plane motion and the stiffness and damping values which involve the out-of-plane motion, i.e. the lateral direction. In this paper, the relations between the in-plane parameters of the 3D tire model and the 2D tire model are given. Based on this relation, it is shown that the 3D tire model can generate exactly the same prediction results as the 2D tire model for tire straight line driving dynamics.
2017-03-28
Technical Paper
2017-01-0066
Shogo Nakao, Akihiko Hyodo, Masaki Itabashi, Tomio Sakashita, Shingo Obara, Tetsuya Uno, Yasuo Sugure, Yoshinobu Fukano, Mitsuo Sasaki, Yoshihiro Miyazaki
This paper presents a high-fidelity electrical-failure simulation environment of belt drive electric power steering (BEPS) system based on our proposed “Virtual Failure Mode and Effects Analysis (vFMEA)” method. The vFMEA system is able to dynamically inject an analog fault into a circuit model of electrical control unit (ECU) of BEPS system, and analyze system-level failure effects and verify software-implemented safety mechanisms, which consequently reduces both cost and time of development. It consists of a cycle-accurate microcontroller model with mass-production software components in binary format implemented, analog and digital circuit models, mechanical models, and a dynamic fault –injection mechanism. In this paper, the vFMEA method was applied to the verification of the safety mechanisms implemented on the ECU of BEPS system, and accuracy of the simulation was evaluated.
2017-03-28
Technical Paper
2017-01-1478
Srinivas Kurna, Sajal Jain, Palish Raja, Laxman Vishwakarma
In automobile, steering system's main function is to allow driver to guide vehicle on desired course. Steering system consists of various components & linkages. Using these linkages, the torque from steering wheel got transferred to Tyre which results in turning of vehicle. The steering components are subjected to various loading conditions over the life of vehicle. As steering components are safety critical elements in vehicle therefore it should not failure in any load condition because failure of any of these component causes vehicle failure. In commercial vehicle segment, vehicle failure means delay in freight delivery & results in huge loss to costumer. Therefore, while designing steering components one should consider all the possible loading which is not possible through theoretical calculation. Therefore, Physical tests has to be done to validate design of steering system which is very costly & time consuming process.
2017-03-28
Technical Paper
2017-01-1495
Srinivas Kurna, Ruchik Tank, Krishna Srikanth Achanta
At the time of invention of road coaches, the vehicle consisted only of an axle with wheels & a body attached. Smooth roads were built for a better ride comfort however they were not consistent. The road coaches were too bumpy & uncomfortable for the passenger along with the driver who was not able to control the vehicle. That's why the engineers had to turn their attention to the suspension system for a better ride comfort & handling. The technology has advanced with the time so has the suspension system. Weveller type leaf spring is one of the many type of suspension systems available in the industry. The job of a suspension system is to maximize the friction between the tires and the road surface, to provide steering stability with good handling and to act as a cushioning device ensuring the comfort of the driver & passengers. The suspension also protects the vehicle itself and any cargo or luggage from damage and wear.
2017-03-28
Journal Article
2017-01-0418
Gregory McCann, Prashant Khapane
An increase in data measurement and recording within vehicles has allowed Anti-lock Braking Systems (ABS) to monitor a vehicles dynamic behavior in far more detail. This increased monitoring helps to improve vehicle response in scenarios such as braking whilst cornering and braking on uneven surfaces. Durability and Robustness (D&R) CAE department within Jaguar Land Rover discovered that the lack of a complex ABS system in virtual vehicle models was contributing to poor lateral and longitudinal loads correlation throughout the suspension and mounting systems. Last year the team started a project to incorporate Continentals ABS system, provided by '©Continental AG' for physical JLR vehicles, into SIMPACK virtual vehicles by means of a co-simulation. The work involved collaboration between 3 departments in Jaguar Land Rover and ultimately led to implementation of the ABS into the JLR wide virtual database.
2017-03-28
Technical Paper
2017-01-0436
Tianjun Zhu, Bin Li
A new extending planar model for multi-axles articulated vehicle with nonlinear tire model is presented. This nonlinear multi-axles articulated vehicle model is specifically intended for improving the model performance in operating regimes where tire lateral force is near the point of saturation, and it has the potential to be applied to extend the specific axles model to any representative configuration of articulated vehicles model. At the same time, the extending nonlinear vehicle model can reduce the model's sensitivity to the tire cornering coefficients. Firstly A nonlinear tire model is used in conjunction with the 6-axle planar articulated vehicle model to extend the ranges of the original linear model into the nonlinear regimes of operation. Secondly the performance analysis of proposed nonlinear vehicle model is verified through the double lane change maneuver on different road adhesion coefficient using Trucksim software.
2017-03-28
Technical Paper
2017-01-1483
Jia Mi, Lin Xu, Sijing Guo, Mohamed A. A. Abdelkareem, Lingshuai Meng
This paper presents a novel application of hydraulic electromagnetic energy-regenerative shock absorber (HESA) into bogie system of railway vehicles. In order to find out the relationship and differences between first suspension system and second suspension system when installed it, HESA is built in AMESim to make comparison studies on the different department suspensions caused by the nonlinear damping behaviors of the HESA. The simulation results show that the system can effectively reduce the impact between wheel and rail tracks, while maintaining good potential to recycle vibratory energy. And the relationships as well as differences between the first suspensions and second suspensions have been concluded, which are useful for the design of HESA-Bogie.
2017-03-28
Technical Paper
2017-01-1503
Jared Johan Engelbrecht, Tony Russell Martin, Piyush M. Gulve, Nagarjun Chandrashekar, Amol Dwivedi, Peter Thomas Tkacik, Zachary Merrill
Most commercial heavy-duty truck trailers are equipped with either a two sensor, one modulator (2S1M) or four sensor, two modulator (4S2M) anti-lock braking system (ABS). Previous research has been performed comparing the performance of different ABS modules, in areas such as longitudinal and lateral stability, and stopping distance. This study focuses on relating ABS module type, and wheel speed sensor placement to trailer wheel lock-up and subsequent impact to tire wear for tandem axle trailers with the nationally common Hendrickson air-ride suspension. Prior to tire wear inspection, functionality of the ABS system was tested electronically using a scan tool communicating with the SAE J560 plug access port on the trailer. Observations were documented on trailers using the 2S1M system with the wheel speed sensor placed on either the front or rear axle of a tandem pair.
2017-03-28
Technical Paper
2017-01-1481
Kyung-bok Lee, Sanghyuk Lee, Namyoung Kim, Bong Soo Kim, Tae soo Chi, Do young Kim
Conventional EPS systems are operated by one type of steering tuning map set by steering test drivers before releasing to customers. That is, steering feeling can't change by other conditions such as road condions(low mu, high mu, unpaved roads) or some specific driving condtions(emergency braking/EPS fail modes/full gasing start). Those conditiions can't afford the drivers consistent steering feel and vehicle driving. This paper approached the techonology detecting those conditions by using vehicle sensors such as wheel speed/vehicle speed/steering angle/steering torque/steering speed and so on. After detecting those conditions and judging which one is the best steering feel and safe vehicle driving, EPS system automatically can be changed with the steering friction level and selection of steering opitmized mapping on several conditions. I believe that this technology can afford the customer "Joy of driving and fun to drive".
2017-03-28
Technical Paper
2017-01-1509
L. Daniel Metz
We examine some characteristics, physical properties and idealized delamination and rupture failure modes of pneumatic tires. After measurement of some typical tire properties, calculations regarding stresses resulting from various tire failure and rupture scenarios are developed.
2017-03-28
Technical Paper
2017-01-1565
Xiangkun He, Kaiming Yang, Xuewu Ji, Yahui Liu, Weiwen Deng
Abstract A vehicle dynamics stability control system based on integrated-electro-hydraulic brake (I-EHB) system with hierarchical control architecture and nonlinear control method is designed to improve the vehicle dynamics stability under extreme conditions in this paper. The I-EHB system is a novel brake-by-wire system, and is suitable to the development demands of intelligent vehicle technology and new energy vehicle technology. Four inlet valves and four outlet valves are added to the layout of a conventional four-channel hydraulic control unit. A permanent-magnet synchronous motor (PMSM) provides a stabilized high-pressure source in the master cylinder, and the four-channel hydraulic control unit ensures that the pressures in each wheel cylinder can be modulated separately at a high precision. Besides, the functions of Anti-lock Braking System, Traction Control System and Regenerative Braking System, Autonomous Emergency Braking can be integrated in this brake-by-wire system.
2017-03-28
Technical Paper
2017-01-0480
Mingde Ding
For structural application, composite parts structure is much more affected by load cases than steel part structure. Engine room bracket of EV, which is structural part and is used to bear Motor Controller, Charger and so on, has different load cases for different EV. Three commonest load cases that are Case 1: bearing 65kg (without suspension part), Case 2: bearing 68kg(including 3.5kg suspension part) and Case 3: bearing 70.1kg (including 5.6kg suspension part). According to topology optimization, structurel 1 was obtained, and then CAE analysis including (strength, stiffness and model) was carried out for abovement three load cases. For Case 1 and Case 2, the analysis result can meet the requirement. However, for Case 3, the stiffness and model analysis result can not satisfy the requirement. To meet the analysis result of Case 3, Structure 1 was optimized and structure 2 was obtained. The CAE analysis was conducted and the results can satisfy the requirements.
2017-03-28
Technical Paper
2017-01-1572
Wesley Kerstens
The detection, and diagnosis, of sensor faults in real-time is necessary for satisfactory performance of vehicle Electronic Stability Control (ESC) and Roll Stability Control (RSC) systems. This paper presents an observer designed to detect faults of a roll-rate sensor that is robust to model uncertainties and disturbances. A reference vehicle roll angle estimate, independent of roll-rate sensor measurement, is formed from available ESC inertial sensor measurements. Residuals are generated by comparing the reference roll angle, and roll-rate, with the observer outputs. Stopping rules based on the current state of the vehicle and the magnitude of the residuals are then used to determine if a sensor fault is present. The system’s low order allows for efficient implementation in real-time on a fixed-point microprocessor. Modification of the roll-rate sensor signal during in vehicle experiments shows the algorithm’s ability to detect faults.
2017-03-28
Technical Paper
2017-01-0459
Salah H. R. Ali, Badr S. N. Azzam, T. A. Osman, A. M. Moustafa
The frictional composite is an important material in braking system for automotive, trucks or heavy-duty vehicles. In this paper, a proposed frictional composite material has been developed to achieve the ISO requirements for heavy-duty vehicle brakes. This new frictional material has been fabricated with various compositions. Tribological, chemical, mechanical, thermal conductivity and acoustic noise level tests have measure its performance compared to other selected commercial samples under certain operating conditions. Additionally, surface characteristics of selected samples have been performed using optical photograph microscopic to insure the materials homogeny after operation. The results of test measurements showed that the proposed frictional material has satisfied the standard recommended values for the friction coefficient with maintaining a lower level of wear. The developed material has also satisfied a good strength and stiffness properties.
2017-03-28
Technical Paper
2017-01-0401
Ye Yuan, Junzhi Zhang, Yutong Li, Chen Lv
Abstract As the essential of future driver assistance system, brake-by-wire system is capable of performing autonomous intervention to enhance vehicle safety significantly. Regenerative braking is the most effective technology of improving energy consumption of electrified vehicle. A novel brake-by-wire system scheme with integrated functions of active braking and regenerative braking, is proposed in this paper. Four pressure-difference-limit valves are added to conventional four-channel brake structure to fulfill more precise pressure modulation. Four independent isolating valves are adopted to cut off connections between brake pedal and wheel cylinders. Two stroke simulators are equipped to imitate conventional brake pedal feel. The operation principles of newly developed system are analyzed minutely according to different working modes. High fidelity models of subsystems are built in commercial software MATLAB and AMESim respectively.
2017-03-28
Technical Paper
2017-01-0402
Zhigang Zhang, Shi Xiaohui, Ye Bin
Abstract Based on the formation mechanism of engaging force of clutch, the engagement was divided into four stages: idle stage, cushion spring stage, diaphragm spring stage and locked stage. The mechanism of transmitted torque in each stage was analyzed and the transmitted torque model of clutch was deduced. Multi-load step analysis method based on finite element was used to analyze the coupling load-deformation characteristics of diaphragm spring and cushion spring in engagement, and the change laws of engaging force, diaphragm spring force and release bearing force were achieved and their coupling interaction were studied. And then change of friction coefficient of clutch with oscillating temperature was measured on friction test rig, and effect of temperature on transmitted torque was further discussed. Finally, simulation results of transmitted torque were validated by the experiment. Results indicate that the transmitted torque in clutch engagement has a nonlinear characteristic.
2017-03-28
Technical Paper
2017-01-0428
Tianqi Lv, Yan Wang, Xingxing Feng, Yunqing Zhang
Abstract Steering returnability is an important index for evaluating vehicle handling performance. A systematic method is presented in this paper to reduce the high yaw rate residue and the steering response time for a light duty truck in the steering return test. The vehicle multibody model is established in ADAMS, which takes into consideration of the frictional loss torque and hydraulically assisted steering property in the steering mechanism, since the friction, which exists in steering column, spherical joint, steering universal joint, and steering gear, plays an important role in vehicle returnability performance. The accuracy of the vehicle model is validated by road test and the key parameters are determined by executing the sensitivity analysis, which shows the effect of each design parameter upon returnability performance.
2017-03-28
Technical Paper
2017-01-0430
Bangji Zhang, Kaidong Tian, Wen Hu, Jie Zhang, Nong Zhang
Abstract This paper introduces a vehicle model in CarSim, and replaces a portion of its standard suspension system with an HIS model built in an external software to implement co-simulations. The maneuver we employ to characterize the HIS vehicle is a constant radius method, i.e. observing the vehicle’s steering wheel angle by fixing its cornering radius and gradually increasing its longitudinal speed. The principles of the influence of HIS systems on cornering mainly focus on two factors: lateral load transfer and roll steer effect. The concept of the front lateral load transfer occupancy ratio (FLTOR) is proposed to evaluate the proportions of lateral load transfer at front and rear axles. The relationship between toe and suspension compression is dismissed firstly to demonstrate the effects of lateral load transfer and then introduced to illustrate the effects of roll motion on cornering.
2017-03-28
Technical Paper
2017-01-0433
Yang Xing, Chen Lv, Wang Huaji, Hong Wang, Dongpu Cao
Abstract Recently, the development of braking assistance system has largely benefit the safety of both driver and pedestrians. A robust prediction and detection of driver braking intention will enable driving assistance system response to traffic situation correctly and improve the driving experience of intelligent vehicles. In this paper, two types unsupervised clustering methods are used to build a driver braking intention predictor. Unsupervised machine learning algorithms has been widely used in clustering and pattern mining in previous researches. The proposed unsupervised learning algorithms can accurately recognize the braking maneuver based on vehicle data captured with CAN bus. The braking maneuver along with other driving maneuvers such as normal driving will be clustered and the results from different algorithms which are K-means and Gaussian mixture model (GMM) will be compared.
2017-03-28
Technical Paper
2017-01-0439
Joydeep Chatterjee, Yuva Kishore Vaddi, Chetan Prakash Jain
Abstract In urban driving conditions, the steering vibration plays a major role for a customer, spending a significant amount of time behind the steering wheel. Considering the urban drive at Indian roads, 1000~1600rpm band becomes primary area of concern. In this paper, study has been conducted to define the target areas as well as its achievement in reference to given driving pattern on a front wheel powered passenger car for steering vibration. During the concept stage of vehicle development, a target characteristic of steering wheel vibration was defined based on the competitor model benchmarking and prior development experience. A correlated CAE model was prepared to evaluate the modification prior to prototype building and verification. Vibration level in all 3 degrees of freedom at the steering wheel location was measured in the initial vehicle prototypes and target areas of improvement are identified.
2017-03-28
Journal Article
2017-01-1493
Dexin Wang, Yiqin Mao, Timothy Drotar, Frank Esser, Hessel van Dijk, Michel Paas
Traditional steering feel tuning and objective verification tests are conducted on vehicle prototypes that are a subset of the total number of buildable combinations of body style, drivetrain and tires. The development time, prototype costs, and number of allowable prototypes are factors that limit the ability to tune and verify all the possible configurations. A new model-based process and a toolset have been developed to enhance the existing steering development process such that steering tuning efficiency and performance robustness can be improved. The innovative method utilizes the existing vehicle dynamics simulation and/or physical test data in conjunction with steering system control models, and provides users with simple interfaces which can be used by either CAE or development engineers to perform virtual tuning of the vehicle steering feel to meet vehicle steering performance targets.
2017-03-28
Journal Article
2017-01-1506
Johannes Wiessalla, Yiqin Mao, Frank Esser
Stability control systems like the ESC (Electronic Stability Control) are triggered when the vehicle extends the thresholds controllable by an average driver. This happens more probable on slippery surfaces, e.g. snow, ice and wet roads. Testing of stability systems on dry asphalt can be done almost any time of the year. Testing on slippery surfaces however is more restricted by weather and proving grounds. Another drawback in testing is the reproducibility of the measurements, since the surface condition changes during the tests and the vehicle behaviour gets more sensitive on low surface. Therefore, simulation enables a good pre-assessment of the stability systems independent from testing conditions. Essential for this is a good knowledge about the contact between road and surface, meaning a good tyre model and a reasonable set of tyre model parameters. Getting these parameters for snow and ice was described in two papers of the authors published before.
2017-03-28
Journal Article
2017-01-1502
Madeline Harper, Janice Tardiff, Daniel Haakenson, Maria Joandrea, Matthew Knych
Tire manufacturers have long grappled with the challenge of balancing the conflicting tire attributes of traction, rolling resistance, and treadwear. Improvements to one of these “magic triangle” attributes often comes at the expense of the other attributes. Recent regulations have further increased the pressure on manufacturers to produce optimized tires with minimal performance compromises. In order to meet this challenge, the tire industry is looking to new material systems beyond the traditional tire tread components. Polymeric materials beyond the base elastomers and processing oils used in tread provide opportunities to modify the physical and viscoelastic properties of tread. In this study, various polymeric materials were evaluated as additives in a model tire tread formulation. Hydrocarbon resin, high styrene resin, and thermoplastic styrene elastomers were added to the model formulation at various loading levels and through various addition strategies.
2017-03-28
Journal Article
2017-01-1507
Prashanta Gautam, Yousof Azizi, Abhilash Chandy
The tire noise is caused due to the complex interactions between the rotating tire and the road surface at the tire/road interface. It is usually caused due to a combination of individually complex noise generation mechanisms, which can be either structural or air related. The influence of each of these noise generation mechanisms may vary, depending on various conditions such as tire design, road surface and operating conditions. Due to the many variables that affect the many noise generation mechanisms in tires, it is usually a very complex task to isolate and categorize those that are present in the overall tire/road noise spectrum. Various approaches are used to categorize noise generation mechanisms in tires. In this paper, a statistical model is used, under the assumption that the tire noise acoustic pressure at a specific frequency band is related to the vehicle speed, in order to study tire noise at different speeds.
2017-03-28
Journal Article
2017-01-1563
Abhijeet Behera, Murugan Sivalingam
Two and three wheeler vehicles are largely used in many developing and under developing countries because of its lower cost, better fuel economy and easy to handle. Although, the construction of them is simpler than the four wheeler vehicle, they pose some problems related to instability. Wobble is the main cause of instabilities in two wheeler and three wheeler vehicles. In this study, a mathematical model was proposed and developed to determine wobble instability of a two wheeler. Nonlinear equations were formulated by using kinematics and d’Alembert’s principle with the help of multi body formalism. The non-linear equations found above were linearized with respect to rectilinear and upright motion, considering no rolling. It led to formation of matrix. The real part of Eigen value of the matrix was found to be negative, implication of whose was an asymptotic stable motion.
2017-03-28
Journal Article
2017-01-1558
Jose Velazquez Alcantar, Francis Assadian, Ming Kuang
Hybrid Electric Vehicles (HEV) offer improved fuel efficiency compared to their conventional counterparts at the expense of adding complexity and at times, reduced total power. As a result, HEV generally lack the dynamic performance that customers enjoy. To address this issue, the paper presents a HEV with eAWD capabilities via the use of a torque vectoring electric rear axle drive (TVeRAD) unit to power the rear axle. The addition of TVeRAD to a front wheel drive HEV improves the total power output. To further improve the handling characteristics of the vehicle, the TVeRAD unit allows for wheel torque vectoring at the rear axle. The proposed TVeRAD design uses a main traction motor to provide traction force to the wheels and a small torque vectoring motor which can distribute torque from one side to the other depending on the direction of the torque vectoring motor torque. Bond graphs are used to develop a dynamic model of the proposed drivetrain architecture.
2017-03-28
Journal Article
2017-01-1569
Amro Elhefnawy, Alhossein sharaf, Hossam Ragheb, Shawky Hegazy
This paper presents an advanced control system, which integrates three fuzzy logic controllers namely; Direct Yaw-moment Control (DYC), Active Roll-moment Control (ARC) and Active Front Steering (AFS) to enhance vehicle cornering and overturning stability. Based on a well-developed and validated fourteen degree of freedom (DOF) full vehicle model with non-linear tyre characteristics, a reference 3-DOF yaw-roll plane vehicle model is introduced to control yaw rate, sideslip angle, and roll angle of the vehicle body. The control actions of both direct yaw and active roll moments are performed by generating differential braking moments across the front wheels, while the control action of the active steering is performed by modifying the steering wheel angle. Different standard cornering tests are conducted in MATLAB / Simulink environment such as J-turn, fishhook and lane change manoeuvres.
2017-03-28
Journal Article
2017-01-1584
Peng Hang, Xinbo Chen, Fengmei Luo, Shude Fang
Compared with the traditional front-wheel- steering (FWS) vehicles, four-wheel-independent-steering (4WIS) vehicles have better handing stability and path tracking performance. In view of this, a novel 4WIS electric vehicle (EV) with steer-by-wire (SBW) system is proposed in this paper. As to the 4WIS EV, a linear quadratic regulator (LQR) optimal controller is designed to make the vehicle track the desired path based on the linear dynamic model. Taking the effect of uncertainties in vehicle parameters into consideration, a robust controller utilizing μ synthesis approach is designed and the controller order reduction is implemented based on Hankel-Norm approximation. In order to evaluate the performance of the designed controllers, numerical simulations of two maneuvers are carried out using the nonlinear vehicle model in MATLAB/Simulink.
2017-03-28
Journal Article
2017-01-1573
Andreas Carlitz, Sebastien Allibert, Thomas Schmitz, Axel Engels
A twistbeam is a very cost effective rear suspension architecture which has drawbacks compared to an independent suspension. One drawback is the lateral compliance during cornering compromising handling. Common solutions to correct this issue are complex reinforcements or an additional Watts linkage. However, these solutions drive high cost and additional weight. The challenge was to find a cost efficient solution which comes close to the functional performance of an IRS. Due to the attachment by bushings, the set-up of a twistbeam is always a compromise between ride comfort and dynamic lag. The more comfort is desired, the softer the bushings will be, resulting in less agility and slower response. The goal was to determine a way to separate ride comfort and dynamic agility. A solution was found using a special set of springs working as a dynamic anti-compliance mechanism.
2017-03-28
Technical Paper
2017-01-1490
Silvia Faria Iombriller
The air suspension development and application has becoming increasingly applied also in commercial vehicles, offering to the driver more dynamic comfort as well as contributing to the reduction of impact loads on highways. Through this project pursuit show the analysis and application of an air suspension system for commercial tractor vehicles application. A special focus was given to pneumatic actuation system, responsible for leveling and control of suspension´s stiffness under different conditions of usage, laden and unladen. The project was conducted starting with the vehicle dynamic performance analysis, evaluating the pneumatic suspension circuit modifications in order to obtain the vehicle dynamic behavior improvement, ensuring directional stability under different maneuvering conditions. For entire development were also used quality tools, considering the possible failure modes and effects as well as virtual simulation tools (Adams) and bench validations.
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