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Viewing 1 to 30 of 10604
2016-06-15
Technical Paper
2016-01-1832
Ramakrishna Kamath
Intermediate shaft assembly is used to connect steering gear to the steering wheel. The primary function of the intermediate shaft is to transfer torsional loads. There is a high probability of noise propagating through the Intermediate shaft to the driver. The current standard for measuring the noise is by performing vehicle level subjective evaluations. If improperly clamped at either of the yokes, a sudden change in the direction of the torsional load on the Intermediate shaft can generate a displeasing noise. Noise can also be generated from the constant velocity joint. Intermediate shaft noise can be measured using a microphone or can be correlated to acceleration values. The benefit of measuring the acceleration over sound pressure level is the reduction of complexity of the test environment and test set up. The nature of the noise in question requires the filtering of low frequency data. This paper presents a new test procedure that has been developed by General Motors.
2016-06-15
Technical Paper
2016-01-1834
Florian Fink, Gregor Koners
Abstract This paper describes the prediction process of wheel forces and moments via indirect transfer path analysis, followed by an analysis of the influence of wheel variants and suspension modifications. It proposes a method to calculate transmission of noise to the vehicle interior where wheel forces and especially moments were taken into account. The calculation is based on an indirect transfer path analysis with geometrical modifications of the frequency response functions. To generate high quality broadband results, this paper also points out some of the main clearance cutting criteria. The method has been successfully implemented to show the influence of wheel tire combinations as well as the influence of suspension modifications. Case studies have been performed and will be presented in this paper. Operational noise and vibration measurements have been carried out on Daimler NVH test tracks. The frequency response functions were estimated in an acoustic laboratory.
2016-06-15
Journal Article
2016-01-1827
Giorgio Bartolozzi, Marco Danti, Andrea Camia, Davide Vige
Abstract The time to market in the automotive industry is constantly decreasing pushing the carmaker companies to increase the efforts in numerical simulations and to decrease the number of prototypes. In the NVH field, this time constraint reflects in moving the well-established finite element simulations towards the so called “full-vehicle simulations”. Specifically, the CAE techniques should be able to predict the complete behavior of the vehicles in mission conditions, so to reproduce some usual tests, such as the “coast down” test on different roads. The aim of this paper is to present a methodology to improve rolling noise simulations exploiting an integrated full-vehicle approach. An accurate modeling of all the subsystems is needed, with particular attention to the wheels and the suspension systems. Therefore, the paper firstly covers the modeling approach used to obtain the FE models of tires and suspension system.
2016-06-15
Technical Paper
2016-01-1765
Kelly Savva, Ahmed Haris, Eliot Motato, Mahdi Mohammadpour, Stephanos Theodossiades, Homer Rahnejat, Patrick Kelly, Alexander Vakakis, Lawrence Bergman, Donald McFarland
Abstract Legislation on vehicle emissions and the requirements for fuel efficiency are currently the key development driving factors in the automotive industry. Research activities to comply with these targets point to engine downsizing and new boosting technologies, which have adverse effects on the NVH performance, durability and component life. As a consequence of engine downsizing, substantial torsional oscillations are generated due to high combustion pressures. Meanwhile, to attenuate torsional vibrations, the manufacturers have implemented absorbers that are tuned to certain frequency ranges, including clutch dampers, Dual Mass Flywheel (DMF) and centrifugal pendulum dampers. These devices add mass/inertia to the system, potentially introducing negative effects on other vehicle attributes, such as weight, driving performance and gear shiftability.
2016-06-15
Journal Article
2016-01-1777
Sebastian Oberst, Zhi Zhang, Joseph CS Lai
Abstract Despite significant progress made in the past 20 years in discovering some of the mechanisms of brake squeal, it remains difficult to predict the underlying friction-induced instabilities reliably. Most numerical analyses are based on linear deterministic analyses of structural vibrations such as the complex eigenvalue analysis (CEA). However, nonlinear multi-scale processes govern friction contact with high sensitivities to operating and/or environmental conditions. In addition, uncertainties in the material properties and boundary conditions such as contact and friction laws are rarely considered. Hence, it is quite common to underpredict or overpredict the number of instabilities and extensive brake noise dynamometer tests are still required in industry to ensure acceptable brake noise performance. In this paper, simplified finite element brake models are used to illustrate the role of nonlinearity in brake squeal.
2016-06-15
Technical Paper
2016-01-1779
Sergio Carvajal, Daniel Wallner, Reinhard Helfrich, Michael Klein
Abstract Numerical methods for brake squeal analysis are widely accepted in industry. The use of complex eigenvalue analysis is a successful approach to predict the appearance of squeal noise. Using simulation in an early design stage reduces time to market, saves costs, and improves the physical behavior and robustness of the brake system. State of the art of brake simulation comprises sampling for many parameter sets in a wide range of interesting values. Based on high performance, stability maps can be created in short time containing many results, which gives a deep insight into the brake behavior under varying parameters. An additional benefit of sampling is the possibility to detect parts with high potential for improving the NHV comfort. In the sequel, mathematical optimization methods like topology optimization or shape optimization are used for systematic improvements.
2016-04-27
Standard
J2530_201604
This SAE Recommended Practice provides performance, sampling, and certifying requirements, test procedures, and marking requirements for aftermarket wheels intended for normal highway use on passenger cars, light trucks, and multipurpose passenger vehicles. For aftermarket wheels on trailers drawn by passenger cars, light trucks or multipurpose vehicles, see SAE J1204. These performance requirements apply only to wheels made of materials included in Table 1 and Table 2. New nomenclature and terms are added to clarify wheel constructions typically not used in OEM applications. The testing procedures and requirements are based on SAE standards listed in the references.
2016-04-27
Standard
J2562_201604
This SAE Recommended Practice provides uniform laboratory procedures for biaxial fatigue testing of wheels intended for normal highway use and temporary use on passenger car vehicles and light trucks and minimum cycle requirement for ferrous wheels for ballasted passenger car applications. The appendices provide scalable load files that are applicable to ballasted passenger cars and ballasted light trucks. A load file for unballasted passenger cars will be added to this document.
2016-04-27
WIP Standard
J773
This SAE Standard covers dimensional, material, and general specifications and methods of test for two types of general purpose conical spring washers, designated type L and type H, for use as loose washers over screws and bolts, and also for use as pre-assembled washers in screw and washer assemblies. Both the type L and type H washers are available in three washer series (narrow, regular and wide), having varied proportions designed to fulfill specific application requirements for load distribution. Where so specified by the user, washers shall be supplied with peripheral teeth. All sizes and types of washers specified in this standard are not necessarily stock production items. Users should consult with manufacturers concerning availability.
2016-04-25
Article
ZF TRW recently announced through its joint venture, Brakes India Ltd, that it has won the first business award for its Electric Park Brake (EPB) system in India. Launching with a major global vehicle manufacturer, the technology will start production in 2017, marking the first launch of its kind for the Indian market, the supplier claims.
2016-04-20
Standard
J3001_201604
This procedure is applicable to modes from 500 and 13,000 Hz. The parameters measured with this procedure are defined as the damping factor, ξ for first nine vibration modes of the beam. The measurement will be done in free-free conditions and with temperature.
2016-04-15
Article
“One Ford," the technological and commercial philosophy the company is energetically pursuing to minimize the need for market-specific vehicle modifications. The Mustang, now on sale in the U.K. and Europe, proves the system works.
2016-04-15
WIP Standard
J1861
This SAE Recommended Practice establishes minimum tolerance requirements for pilot operated and mechanically actuated modulating type valves, and through type valves used in the service brake control system when tested in accordance with the test procedure outlined in SAE J1859. This document applies to the nominal input-output characteristics as specified by vehicle original equipment manufacturer and labeled by the valve manufacturer as outlined in SAE J1860. The tolerance requirements will include: a. Crack (opening) pressure or force. Crack pressure may be measured at the initial output pressure or as the pressure differential before output pressure exceeds 14 kPa (2 psi). Crack force may be measured at initial output pressure or before output pressure exceeds 14 kPa (2 psi). b. Pressure differential (input-output)
2016-04-15
WIP Standard
J1860
This SAE Recommended Practice applies to those air brake system valves used to control the vehicle service brakes and test procedures defined by SAE J1859 to measure performance characteristics. This Recommended Practice adheres to standard industry practice of using English units for specifying valve characteristics.
2016-04-15
Journal Article
2015-01-9020
Emre Sert, Pinar Boyraz
Abstract Studies have shown that the number of road accidents caused by rollover both in Europe and in Turkey is increasing [1]. Therefore, rollover related accidents became the new target of the studies in the field of vehicle dynamics research aiming for both active and passive safety systems. This paper presents a method for optimizing the rear suspension geometry using design of experiment and multibody simulation in order to reduce the risk of rollover. One of the major differences of this study from previous work is that it includes statistical Taguchi method in order to increase the safety margin. Other difference of this study from literature is that it includes all design tools such as model validation, optimization and full vehicle handling and ride comfort tests. Rollover angle of the vehicle was selected as the cost function in the optimization algorithm that also contains roll stiffness and height of the roll center.
2016-04-14
WIP Standard
J1859
This SAE Recommended Practice establishes uniform test procedures for determining input-output characteristics for those pilot-operated and mechanically actuated, modulating-type valves and through-type valves used in the service brake control system.
2016-04-13
WIP Standard
J1982
This SAE Recommended Practice establishes uniform engineering nomenclature for the most common wheel constructions, and their components used on passenger cars, light trucks, and multipurpose vehicles. These wheel constructions are welded “Disc Wheels”, “Cast Wheels” and “Forged Wheels”. This nomenclature and the accompanying drawings are intended to define fundamental wheel terms rather than to provide a comprehensive tabulation of all wheel design types.
2016-04-12
Standard
AIR5490A
This document provides information on contamination and its effects on brakes having carbon-carbon composite friction materials (carbon). Carbon is hygroscopic and porous, and therefore readily absorbs liquids and contaminants. Some of the contaminants can impact intended performance of the brake. This document is intended to raise awareness of the effects of carbon brake contamination and provide information on industry practices for its prevention. Although not addressed in this report, contaminants can cause problems with other landing system components including tires.
2016-04-07
Magazine
Defying the disruptors and driving innovation Four top engineering executives discuss how their "traditional" companies are finding new technology opportunities and business growth amid the start-ups-and are even doing some disrupting themselves. Preparing for a 48-volt revival The quest to improve fuel economy is not waning, nor is the desire to achieve higher mpg through the use of just the right lightweight material for the right vehicle application. Additive manufacturing enhances GTDI pistons Selective Laser Melting may help manufacture future gasoline-engine pistons with enhanced heat-transfer properties and reduced weight.
2016-04-05
Standard
J230_201604
This SAE Recommended Practice covers a high-strength corrosion-resisting steel wire, uniform in mechanical properties, intended for the manufacture of springs and wire forms. It covers processing requirements of springs and forms fabricated from this wire.
2016-04-05
Standard
J217_201604
This SAE Recommended Practice covers a high-quality corrosion resisting steel wire, cold drawn, formed, and heat treated to produce uniform mechanical properties. It is magnetic in all conditions. It is intended for the manufacture of springs and wire forms that are to be heat treated after forming to enhance the spring properties. This document also covers processing requirements of the springs and forms fabricated from this wire.
2016-04-05
Standard
J510_201604
This SAE Standard is limited to concise specifications promoting an adequate understanding between spring maker and spring user on all practical requirements in the finished spring. The basic concepts for the spring design and for many of the details have been fully addressed in HS-J788, SAE Information Report, Manual on Design and Application of Leaf Springs, which is available from SAE Headquarters. NOTE: For leaf springs made to metric units, see SAE J1123.
2016-04-05
Technical Paper
2016-01-1566
Liangyao Yu, Xiaoxue Liu, Kefeng Yang, Xiaohui Liu, Shuhao Huo
This paper focuses on reviewing the existing studies of in-tire energy harvesting systems. Energy harvesting systems are widely applied in different areas. But studies in the application of energy harvesters embedded in tires for vehicle control are still rare, most of which focus on solving the problem of power supply of tire pressure sensors. Traditionally the sensors are powered by an embedded battery, which must be changed periodically due to the limited energy storage. Furthermore, the number of in-tire sensors will increase as safety of vehicles has drawn more attention, requiring more in tire electricity supply. So a substitution of the battery, the in-tire energy harvesting system, is worth studying. Currently introduced methods of in-tire energy harvesting principles include piezoelectric, electromagnetic and electrostatic. The source of the energy can be in tire vibration, deformation, rotation and so on.
2016-04-05
WIP Standard
J1301
The scope and purpose of this SAE Recommended Practice is to provide a classification system for deformation sustained by trucks involved in collisions on the highway. Application of the document is limited to medium trucks, heavy trucks, and articulated combinations. The TDC classifies collision contact deformation, as opposed to induced deformation, so that the deformation is segregated into rather narrow limits or categories. Studies of collision deformation can then be performed on one or many data banks with assurance that data under study are of essentially the same type. Many of the features of the SAE J224 MAR80 have been retained in this document, although the characters within specific columns vary. Each document must therefore be applied to the appropriate vehicle type. It is also important to note that the Truck Deformation Classification (TDC) does not identify specific vehicle configurations and body types.
2016-04-05
Technical Paper
2016-01-1562
Hongyu Zheng, Jinghuan Hu, Jidong Lv
There is no mechanical connection between steering wheel and front wheel in vehicle Steer by Wire. The advantages of steer by wire system such as its modular structure and variable steering ratio provide wide development prospect for vehicle performance. Accurate, stable coupling between modules is the basis of its normal operation, the property of variable steering ratio influences vehicle handling stability directly, they are all the core component of Steer-by-Wire system control method. In steering angle ratio and road feeling control algorithm of steer by wire system, the parameters of steering system and electrical machine have important influence on control algorithm. Therefore, establishing steer by wire vehicle simulation platform and steer by wire experimental verification platform should be arranged at first.
2016-04-05
Standard
J1528_201604
Test Material: Only fully processed new springs which are representative of springs intended for the vehicle shall be used for the tests. No complete spring or separate leaf shall be used for more than one test.
2016-04-05
Standard
J1123_201604
This SAE Standard is limited to concise specifications promoting an adequate understanding between spring maker and spring user on all practical requirements in the finished spring. The basic concepts for the spring design and for many of the details have been fully dealt with in HS J788.
2016-04-05
Journal Article
2016-01-0305
Subhash Hanmant Bhosale, Aditya Malladi, Abhijit Londhe
Abstract Designing a vehicle chassis involves meeting numerous performance requirements related to various domains such as Durability, Crashworthiness and Noise-Vibration-Harshness (NVH) as well as reducing the overall weight of chassis. In conventional Computer Aided Engineering (CAE) process, experts from each domain work independently to improve the design based on their own domain knowledge which may result in sub-optimal or even non-acceptable designs for other domains. In addition, this may lead to increase in weight of chassis and also result in stretching the overall product development time and cost. Use of Multi-Disciplinary Optimization (MDO) approach to tackle these kind of problems is well documented in industry. However, how to effectively formulate an MDO study and how different MDO formulations affect results has not been touched upon in depth.
2016-04-05
Journal Article
2016-01-0387
Yunkai Gao, Jingpeng Han, Jianguang Fang, Shihui Wang
Abstract A compiled method of the programmed load spectrum, which can simplify and accelerate the fatigue bench test of a car body, is proposed and its effectiveness is checked by the fatigue simulation. By using the multi-body dynamics model with a satisfactory accuracy, the virtual iteration is applied to cascade body loads from the wheel hubs. Based on the rain-flow counting method and statistics theory, the distributions of the body loads are analyzed, and then the programmed load spectrum is compiled and simplified. Through comparative study, the simulation results of random and programmed load spectrum are found to agree well with each other in terms of the damage distribution and fatigue life, which demonstrates the effectiveness of the presented method.
2016-04-05
Technical Paper
2016-01-0381
Moorthy Senniappan, Rajendra More, Shreyas Bhide, Siddesh Gowda
Abstract In the present scenario, automobile manufacturers are forced to reduce the weight of each components through design optimization. In a bid to enhance the fuel efficiency and load carrying capacity of the vehicle; however this approach may not be practical for all the parts in real life, and the engineer will end up adding further mass to the component. This is carried out to enhance the strength of the component, since considerable over load application in real world usage condition which can damage the component drastically. In this paper, steering tie rod arm of a heavy commercial vehicle was taken as a case study. The Steering tie rod arm is a part which connects the wheel spindle with steering system linkage i.e. Track rod. Track rod transfers the steered force from one wheel to another wheel and steering tie rod arm transfers the force from track rod to wheel spindle to steer both the wheels in same direction.
Viewing 1 to 30 of 10604

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