Criteria

Text:
Display:

Results

Viewing 1 to 30 of 2302
Event
2015-06-22
This session includes papers in the areas of static, dynamic, and fatigue characterization of elastomers, bushings, mounts and shock absorbers used in the mobility industry. Particular emphasis is given to new and innovative analysis and testing methodologies to quantify the non-linear properties of these systems in addition to the effects of temperature, frequency, and aging. Papers dealing with specific applications and case studies of existing methodologies are also welcome.
Training / Education
2014-11-17
While a variety of new engineering tools are becoming available to assist in creating optimal vehicle designs, subjective evaluation of vehicle behavior is still a vital tool to ensure desired braking, handling, and other dynamic response characteristics. In order to better prepare today's engineer for this task, this course offers twelve modules devoted to the key fundamental principles associated with longitudinal and lateral vehicle dynamics. Each focused classroom session is paired with an on-track exercise to immediately reinforce these concepts with a dedicated behind-the-wheel driving session, effectively illustrating these principles in the real world.
Training / Education
2014-11-12
Just as the chassis and suspension system provides an ideal framework for the automobile, this popular SAE seminar provides an informative framework for those involved in the design of these important systems. Emphasizing the fundamental principles that underlie rational development and design of suspension components and structures, this course covers the concepts, theories, designs and applications of automotive suspension systems.
Training / Education
2014-11-03
                                                                 Understanding vehicle dynamics is one of the critical issues in the design of all vehicles, including heavy trucks. This seminar provides a comprehensive introduction to the fundamentals of heavy truck dynamics. It covers all of the critical subsystems that must be considered by designers and decision makers in determining the effect of various components on heavy truck dynamics. This seminar begins where the tires meet the ground, progressing up through the various components and bringing together the theory and practice of heavy truck dynamics.
Training / Education
2014-10-20
This seminar will present an introduction to Vehicle Dynamics from a vehicle system perspective. The theory and applications are associated with the interaction and performance balance between the powertrain, brakes, steering, suspensions and wheel and tire vehicle subsystems. The role that vehicle dynamics can and should play in effective automotive chassis development and the information and technology flow from vehicle system to subsystem to piece-part is integrated into the presentation. Governing equations of motion are developed and solved for both steady and transient conditions. Manual and computer techniques for analysis and evaluation are presented.
Event
2014-10-09
This session focuses on theoretical and experimental vehicle dynamics aspects of both on- and off-road vehicles. Papers on topics such as off-road vehicle chassis and suspension, NVH, driver/operator comfort, as well as on-road suspension design, active and semi-active suspension systems and controls, and full vehicle dynamic studies are welcomed. Topics ranging from on-road vehicles to trucks to construction and mining machinery are covered in CV205.
Event
2014-10-07
Active Safety Systems are becoming commonplace on commercial vehicle systems. These systems can include but are not limited to safety systems that assist to mitigate or in some cases, avoid accidents by intervening through visual/audible warnings, providing steering assist or active braking to slow the vehicle down. The size and complexity of the commercial vehicles offers some challenges to the application of these systems. This panel session will bring together experts in the area to discuss the recent developments and challenges going forward in the application of Anti-lock braking systems, Traction control systems, Electronic Stability Control systems, Lane Keeping Systems, Adaptive Cruise Control, Autonomous Emergency Braking system for commercial vehicles.
Event
2014-10-07
This technical session invites papers on dynamics and performance of conventional and unmanned, on-road/off-road vehicles with emphasis on dynamics and design of chassis, suspension, tires, and tracks. In the area of vehicle chassis with four and more number of driving wheels, papers are welcome, but not limited to: various types of suspensions and their interaction with the driving gear, steering, and driveline systems. Research papers presenting results on analysis, optimization, and control of tire dynamics and design for road and terrain vehicle applications are encouraged to be submitted to this session. Special attention is also given to rubber-track chassis systems and their asphalt passability and terrain mobility. Papers on conventional track system dynamics, design, and reliability issues are also invited. Energy efficiency issues, stochastic modeling, smoothness of ride, integrated design of chassis subsystems are also considered.
Technical Paper
2014-10-01
Christopher Gill, Christopher Knight, Scott McGarry
Vehicle shock absorbers are designed to dissipate kinetic energy through frictional viscous forces. In some circumstances, this can be in the order of kilowatts of instantaneous power dissipation. This study quantitatively assesses the vehicle damper system energy dissipation of a low-mass utility vehicle and a high-mass hauling vehicle, using empirically derived regression models of the working dampers and custom data logging equipment. The damper force and power is derived from post-processing of the measurement of critical damper metrics, including linear velocity and temperature. Under typical operating conditions, the low-mass utility vehicle showed an average power dissipation of 39 W for a single shock absorber, and approximately 150 W for a complete vehicle-damper model. The high-mass hauling vehicle demonstrated an average power dissipation of 102 W for a single shock absorber, and approximately 600 W for a complete vehicle-damper model under laden operating conditions. Our results provide evidence of the amount of energy available for harvesting from a vehicles' damper system using a kinetic energy recovery device.
Technical Paper
2014-09-30
Xianjian Jin, Guodong Yin, Youyu Lin
Knowledge of vehicle dynamics variables is very important for vehicle control systems that aim to improve handling characteristics and passenger safety. However for both technical and economical reasons some fundamental data (e.g., Lateral tire-road forces and vehicle sideslip angle) are not measurable in a standard car. This paper proposes a novel Interacting Multiple Model Filter-Based method to estimate lateral tire-road forces by utilizing real-time measurements. The method uses measurements (yaw rate, roll rate, accelerations, steering angle and wheel speed) only from sensors which have already been integrated in modern cars. The estimation method of lateral tire-road forces is based on an interacting multiple model (IMM) filter that integrates in-vehicle sensors of in-wheel-motor-driven electric vehicles to adapt multiple vehicle-road system models to variable driving conditions. Considering extended roll dynamics and load transfer, a four-wheel nonlinear vehicle dynamics model (NVDM) is built.
Technical Paper
2014-09-30
Boris Belousov, Tatiana I. Ksenevich, Vladimir Vantsevich, Sergei Naumov
An open-link locomotion module (OLLM) is an autonomous energy self-sufficient locomotion setup for designing ground wheeled vehicles of a given configuration that includes drive/driven and steered/non-steered wheels with individual suspension and brake systems. Off-road applications include both trucks and trailers. The paper concentrates on the module's electro-hydraulic suspension design and presents results of analytical and experimental studies of a trailer with four driven (no wheel torque applied) open-link locomotion modules. On highly non-even terrain, the suspension design provides the sprung mass with sufficient vibration protection at low level of normal oscillations, enhanced damping and stabilized angular movements. This is achieved by the introduction of two control loops: (i) a fast-acting loop to control the damping of the normal displacements; and (ii) a slow-acting control loop for varying the pressure and counter-pressure in the suspension system. Thus, two separate but coordinated controls were designed for both loops to act under small (less than ±7 degrees) and big (larger than ±7 degrees) pitch and roll angles of a vehicle designed with a set of the modules.
Technical Paper
2014-09-30
Guoying Chen, Dong Zhang
Abstract Four-wheel independent control electric vehicle is a new type of x-by-wire EV with four wheels independent steering and four wheels independent drive/brake systems. In order to take full advantage of the vehicle's performance potential, this paper presents a novel integrated chassis control strategy. In the paper, the strategy is designed by the hierarchical control structure and divided into integrated control layer and allocation layer. By this method, the control logical can be modularized and simplified. In the integrated control layer, Model Prediction Control (MPC) is adopted to design the integrated control unit, which belongs to be a kind of local optimization algorithm with feedback correction features. Using this method could avoid the system performance degradation caused by the control model mismatch. The control allocation layer is to optimally distribute the vehicle control forces to the steering/driving/brake actuators on each wheel. In order to maximize the use of the tire adhesions, the algorithm sets the tire load rate minimized as the control target.
Technical Paper
2014-09-30
Dong Zhang, Changfu Zong, Guoying Chen, Pan Song, Zexing Zhang
Abstract A full drive-by-wire electric vehicle, named Urban Future Electric Vehicle (UFEV) is developed, where the four wheels' traction and braking torques, four wheels' steering angles, and four active suspensions (in the future) are controlled independently. It is an ideal platform to realize the optimal vehicle dynamics, the marginal-stability and the energy-efficient control, it is also a platform for studying the advanced chassis control methods and their applications. A centralized control system of hierarchical structure for UFEV is proposed, which consist of Sensor Layer, Identification and Estimation Layer, Objective Control Layer, Forces and Motion Distribution Layer, Executive Layer. In the Identification and Estimation Layer, identification model is established by utilizing neural network algorithms to identify the driver characteristics. Vehicle state estimation and road identification of UFEV based on EKF and Fuzzy Logic Control methods is also conducted in this layer. In the Objective Control Layer, a real-time ideal reference model of vehicle dynamics for drivers with different characteristics are built up with Radical Basis Function (RBF) neural network by using the driving simulator test data, which is used for the control objective of the UFEV.
Technical Paper
2014-09-30
Yiting Kang, Subhash Rakheja, Wenming Zhang
Abstract A range of axle suspensions, comprising hydro-pneumatic struts and diverse linkage configurations, have evolved in recent years for large size mining trucks to achieve improved ride and higher operating speeds. This paper presents a comprehensive analysis of different independent front suspension linkages that have been implemented in various off-road vehicles, including a composite linkage (CL), a candle (CA), a trailing arm (TA), and a double Wishbone (DW) suspension applied to a 190 tons mining truck. Four different suspension linkages are modeled in MapleSim platform to evaluate their kinematic properties. The relative kinematic properties of the suspensions are evaluated in terms of variations in the kingpin inclination, caster, camber, toe-in and horizontal wheel center displacements considering the motion of a hydro-pneumatic strut. The results revealed the CL and DW suspensions yield superior kinematic response characteristics compared to the CA and TA suspensions. Toe-in and horizontal wheel center displacements of the CA and TA vary significantly, which could strongly affect the vehicle handling performance and cause greater tire wear.
Technical Paper
2014-09-28
Mohamed Samy Barakat
The Braking System is the most crucial part of the racing vehicle. There is no doubt, that if only one minority failure in the braking system took place, this would be more than enough reason to cause the racing team disqualification from the competition. Time is the main and the most important criteria for any racing competition; on the other hand the formula student “FS UK SAE” competition care the most about developing the automotive engineering sense in the students by putting them under strict rules normally taken from the original version “formula 1” to encourage their creativity to reach the optimum performance under these strict rules. One of the most important rules is “No Braking by wire”, and the obvious consequences are more stopping distance and time. Braking distance is a critical facture in achieving racing success in a competitive domain. This report will cover using the bias bar, dynamic weight distribution “before and after braking” and carefully choosing the braking and suspension system components dimensions, in order to fulfill the main functions of “ABS and EBD” which are preventing the wheels from lock-up and preventing side skid of the vehicle during cornering in the different dynamic tests with full consideration of the maximum approachable deceleration of the vehicle without locking up without using any kind of electronic “actuators or control”.
Video
2014-09-11
Senior Editor Lindsay Brooke recently tested a McLaren 650S, with surprising results.
WIP Standard
2014-07-21
No scope available.
Technical Paper
2014-06-30
Hiromichi Tsuji, Satoshi Takabayashi, Eiji Takahashi, Hitoshi Murakami, Shinichi Maruyama
A finite element (FE) model of vibro-acoustic coupling analysis, such as a vehicle noise and vibration, is utilized for the improvement of the performance in the vehicle development phase. However, the accuracy of the analysis is not enough for substituting a prototype phase with a digital phase in the product development phases. Therefore, conducting the experiments with the prototype vehicle or the existed production vehicle is still very important for the performance evaluation and the model validation. The vehicle noise transfer function of the road noise performance cannot be evaluated with the existed excitation equipment, such as the 3 or 6 directional electromagnetic shaker. Therefore, this paper proposes new experimental method to measure the road noise vehicle transfer function. This method is based on the reciprocity between the tire contact patch and the driver's ear location. The reaction force sensor of the tire contact patch is newly developed for the reciprocal loud speaker excitation at the passenger ear location.
WIP Standard
2014-06-16
This recommended practice is a source of information for body and trim engineers and represents existing technology in the field of on-highway vehicle seating systems. It provides a more uniform system of nomenclature, definitions of functional requirements, and testing methods of various material components of motor vehicle seating systems.
Magazine
2014-06-03
Systems-engineering a new 4x4 benchmark Chrysler Powertrain teamed with AAM to create the industry's most capable, sophisticated-and arguably most fuel-efficient-AWD/4WD driveline. Top engineers talk about their collaboration. Achates aims at 2025 light-truck power After more than a decade of steady development, Achates Power's opposed-piston two-stroke diesel is impressing powertrain experts with its test results and pace of technical progress. Lighter, stronger chassis Development of a new high-strength aluminum casting alloy for the production of suspension components.
Technical Paper
2014-05-07
Eraldo de Jesus Soares, Alan M. Oliva, Camilo A. Adas, Fernando C. Dusi, Paulo Sergio P. Santos, Marco A. Fogaça Accurso, Marcus Kliewer
Abstract The purpose of this paper is to show a multiaxial bench test for static and dynamic testing of leaf springs for suspension of commercial vehicles. The bench test simulates the critical operating conditions (track, ramp, speed bump on track, curves and braking), with stroke control for strength and deformation analysis. One of the main advantages in bench test is to reduce the time of the test, its repeatability, its cost saving and monitoring its performance through inspections and graphic records. The aim of the test is to evaluate the behavior in durability of the components, to analyze the possible failure mode and to be able to approve or reject the component based on the test's results. Criteria were set to accelerate the test by comparing signals measured on the field and bench test with deflection by stress curves. These criteria were maintained under extreme conditions for longer than the observed in previous and real applications. With this, the low incidence of strength and stroke is measured by optimizing the time of the test.
Technical Paper
2014-05-07
Claudio Gomes Fernandes, Eric Noguchi, Rômulo Castro, Uilian Almeida
Abstract Automotive industry has shown, in the recent years, a dramatically increase of competition at emergent markets. The incoming of new Brands, for example in the Brazilian market, is causing the OEMs to decrease costs while increase quality, which represents a big challenge nowadays. In this challenging scenario, virtual simulation has become mandatory. While cutting costs since no physical prototypes are required, virtual models also reduces development time. Time to time, as computers processing capacity grows, virtual models are becoming more and more accurate, being able to capture even high non-linear phenomena, which ten years ago would not be feasible. It is also known the natural tendency of vehicle dynamics engineers to develop shock absorber tuning only by means of subjective evaluation. Many reasons can be raised to this tendency, but one of them is the lack of representation of the entire shock absorber behavior in the virtual models. In this sense, the present work shows an attempt to capture the main non-linearities of shock absorbers that affect the most the vehicle behavior in terms of ride and handling.
Technical Paper
2014-05-07
Frederico A. A. Barbieri, Vinicius de Almeida Lima, Leandro Garbin, Joel Boaretto
Abstract Brazil presents a very diverse road and traffic conditions and due to several factors the number of truck accidents is very high. Inside truck accidents group, the one that causes the highest number of losses and fatalities is the rollover crash and understanding rollover dynamics is very important to prevent such events. The diversity of cargo vehicles arrangements requires a detailed study regarding the dynamic behavior these vehicle combinations in order to increase operation safety. The same tractor unit can be used with different types and numbers of trailers and/or semi-trailers, each one with different suspension configurations. These truck combinations have distinct dynamic performances that need evaluation. In this sense, this work presents a first phase study on the dynamic behavior of different types of cargo vehicle configuration. A 6×2 tractor is combined with a two distinct grain semi-trailer with different types of suspension: pneumatic and leaf spring. The study is conducted in order to verify the difference in dynamic behavior and the resulting stability of the two configurations in different conditions of speed and maneuvers.
Technical Paper
2014-05-07
Marcos dos Santos, Ricardo Guedes Manini, Jayme B. Curi, Cleber Chiqueti
Abstract ”U” bolts are fixing elements and they are used to clamp an elastic joint. From the past, they still looking as an old design and unfortunately, suspension engineers are not specialists in fasteners and elastic joints. That is why we will show important assumptions and concepts to design and specifications this clamp element “U” bolt and its influence over leaf-springs. Currently, “U” bolt is used to clamp an elastic or elastic-plastic joint of heavy duty suspension, formed by leaf-spring, axle, spring pad, “U” bolt plate. This kind of suspension is typically used to trucks, buses and trailers. We are wondering, which one important assumption that an engineer must be careful when designs a new suspension changing from old designs to an updated technology. We provide a theoretical analysis and a FEA analysis to compare torque efficacy x leaf-spring reactions and what are effects this relationship can cause in a suspension. To have a shortest development time and provide back an expected result from the suspension system, engineers should to consider more and new assumptions, evaluate virtual and practical performance of leaf-springs with “U” bolt designed to clamp all elastic joint and even the correct torque specification to the “U” bolt.
Technical Paper
2014-05-07
Alfred Memmel, Anibal Berberich
Abstract Variable Damping systems for commercial vehicle applications have been in the market for several years now. The systems modify damping according to the actual demand within milliseconds. This reduces vertical accelerations which lead to improved comfort while maintaining vehicle stability and safety at the same time. Driver, cargo and vehicle are better protected. The technical effort for variable damping systems was in the past rather high and affected a limited market penetration. On the other side the used control algorithms did not tap the full potential of the system performance. New concepts, like integration of sensors or concentration on the most relevant axle, in combination with new control algorithms, simplifies the systems architecture and improves the performance. Besides the functional advantages, the system improves vehicle efficiency as it reduces the energy dissipated by the dampers. This energy would have to be generated by the engine. Less damping also relates to reduction of fuel consumption.
Technical Paper
2014-05-07
Saulo Machado Rodrigues, André Soares, Henrique Zambon, Odair Berti, Rudimar Mazzochi
During the field tests of a prototype of a cabin suspension assembly applied in a commercial vehicle it has been evidenced the premature failure in the torsion bar. Due to this failure, which happened with 20% of approval total test, one verified that the adding of a lateral displacement control bar (Panhard), attached to the torsion bar, promoted a significant additional force to it, which was not predicted in the initial dimensioning. Due to that, it was executed a re-design of the assembly, paying a special attention to the torsion bar, considering the influence of Panhard bar. To do that, several numerical simulations were carried out, using the finite element software Abaqus, whose boundary conditions were determined based on data collected in the field tests. Lately, the new concepts developed were submitted to bench tests, applying hydraulic actuators to apply the loads, in which one executed an experimental verification of stresses to calibrate the numerical models.
Technical Paper
2014-05-07
Fabio Augusto Schuh, Leandro Luís Corso, Leonardo Hoss
Abstract Applying knowledge available at technical literature for cycle counting, damage caused by each load cycle through S-N curve, and fatigue damage accumulation by Palmgren-Miner rule, durability prediction is performed for a leafspring of a commercial vehicle with 6×4 suspension system. Max principal tension is measured by means of strain gages in the most representative points for fatigue life of the leafspring, determined with FEA, while vehicle runs over off-road track in a proving ground. Load and tension are also measured in a laboratory bench test for this component. Correlation between off-road track and bench test is then performed. Finally, representative samples of the component are tested with dynamic loading until fatigue fracture in bench test, and using data from these tests, statistical analysis is performed with application of Weibull distribution, allowing life prediction in statistical terms.
Viewing 1 to 30 of 2302

Filter

  • Range:
    to:
  • Year: