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This SAE Standard specifies a message set, and its data frames and data elements specifically for use by applications intended to utilize the 5.9 GHz Dedicated Short Range Communications for Wireless Access in Vehicular Environments (DSRC/WAVE, referenced in this document simply as “DSRC”), communications systems. Although the scope of this Standard is focused on DSRC, this message set, and its data frames and data elements have been designed, to the extent possible, to also be of potential use for applications that may be deployed in conjunction with other wireless communications technologies. This Standard therefore specifies the definitive message structure and provides sufficient background information to allow readers to properly interpret the message definitions from the point of view of an application developer implementing the messages according to the DSRC Standards.

This paper summarizes the techniques and guidelines which were used to reduce the driver perceived noise level of a 145-210 HP series of agricultural tractors. Graphs of case study test results and comments on subjective noise quality are provided to guide the acoustic novice through the complexities of the vehicle sound environment in a methodical problem solving format.

Transfer path analysis is a powerful tool to support the vehicle NVH development. On the one hand it is a fast method to gain an overview of the complex interplay in the vehicle noise generation process. On the other hand it can be used to identify critical noise paths and vehicle components responsible for specific noise phenomena. FEV has developed several tools, which are adapted to the considered noise phenomena: Powertrain induced interior noise and vibration is analyzed by VINS (Vehicle Interior Noise Simulation), which allows the deduction of improvement measures fast enough for application in the accelerated vehicle development process. Further on vehicle/powertrain combinations not realized in hardware can be evaluated by virtual installation of the powertrain in the vehicle, which is especially interesting in the context of engine downsizing from four to three or six to four cylinders.

General Motors Powertrain Group (GMPTG) has developed an all new small block V8 engine, designated LS1, for introduction into the 1997 Corvette. This engine was designed to meet both customer requirements and competitive challenges while also meeting the ever increasing legislated requirements of emissions and fuel economy. This 5.7L V8 provides increased power and torque while delivering higher fuel economy. In addition, improvements in both QRD and NVH characteristics were made while meeting packaging constraints and achieving significant mass reductions.

The potential contributions of acoustical technology to manufacturing companies pervade nearly all of its functions from marketing and product planning to design engineering and quality control. Despite this, however, companies generally feel uneasy when they embark on programs to use acoustics in their operations because the technology seems complicated and somehow harder to “get a handle on” than it is in other cases. But the issues of product sound, and the benefits of acoustics on a diagnostic tool are too important to ignore, so in this paper we discuss these issues in a “20 questions” format to help planners, engineers and managers as they proceed to implement acoustical technology in their organizations.

The 2018 Ultimate GD&T Pocket Guide explains the most common rules, symbols, and concepts used in geometric dimensioning and tolerancing. This one-of-a-kind reference guide includes more than 100 detailed examples to illustrate concepts. Numerous charts for quick reference provide explanations of each GD&T symbol, modifier, and more. This valuable on-the-job resource clarifies how to interpret standard-compliant technical drawings that use ASME Y14.5-2018.

Contact the appropriate representative of the 2023 Noise and Vibration Conference and Exhibition.

The term “3 inch ice shapes” has assumed numerous definitions throughout the years. At times it has been used to generally characterize large glaze ice accretions on the major aerodynamic surfaces (wing, horizontal stabilizer, vertical stabilizer) for evaluating aerodynamic performance and handling qualities after a prolonged icing encounter. It has also been used as a more direct criterion while determining or enforcing sectional ice shape characteristics such as the maximum pinnacle height. It is the authors’ observation that over the years, the interpretation and application of this term has evolved and is now broadly misunderstood. Compounding the situation is, at present, a seemingly contradictory set of guidance among (and even within) the various international regulatory agencies resulting in an ambiguous set of expectations for design and certification specialists.

In order to reproduce heavy bass with a small diameter loudspeaker for automotive use similar to the intensity and low distortion of a home-use Hi-Fi system, a large volume velocity must be obtained. This is done by lowering the minimum resonant frequency of system and by linearly expanding the amplitude range of diaphragm. We have developed a 3-D woofer system using a centering suspension that consists of four tubes of square cross-section continuously laid in the circumferential direction and a cone suspension that has V-shaped pleats in both of the circumferential and diameter directions for the vibration system. The results are good acoustic characteristics in an automotive cabin that are low in distortion with high output in the low frequency range up to 100Hz.

Beside the automotive industry, where 2-cylinder inline engines are catching attention again, twin-cylinder configurations are quite usual in the small engine world. From stationary engines and range-extender use to small motorcycles up to big cruisers and K-Cars this engine architecture is used in many types of applications. Because of very good overall packaging, performance characteristics and not least the possibility of parts-commonality with 4-cylinder engines nearly every motorcycle manufacturer provides an inline twin in its model range. Especially for motorcycle applications where generally the engine is a rigid member of the frame and vibrations can be transferred directly to the rider an appropriate balancing system is required.

Traditional acoustic measurements inside any cavity have historically been conducted with a small number of microphones. By this means it is possible to gain information about parameters like frequencies, orders and sound pressures. However, a space-selective analysis is nearly impossible and it is not feasible to find the position of the sound sources in space in a practical way. While traditional beam forming systems with planar microphone arrays have enlarged the possibilities of acoustic measurements, they do not give comprehensive information about the sound sources in the entire vehicle interior. Therefore, the components of the Acoustic Camera of the GFal were extended by a spherical, acoustically transparent and omni-directional array. A new option is to map onto a common 3D-CAD-model of the object of interest, for instance a vehicle interior. The advantages and disadvantages of 2D- and 3D-mappings will be discussed in the paper.

Accurate measurement of countersinks in curved parts has always been a challenge. The countersink reference is defined relative to the panel surface which includes some degree of curvature. This curvature thus makes accurate measurements very difficult using both contact and 2D non-contact measurements. By utilizing structured light 3D vision technologies, the ability to very accurately measure a countersink to small tolerances can be achieved. By knowing the pose of the camera and projector, triangulation can be used to calculate the distance to thousands of points on the panel and countersink surface. The plane of the panel is then calculated using Random Sample Consensus (RANSAC) method from the dataset of points which can be adjusted to account for panel curvatures. The countersink is then found using a similar RANSAC method.

A continuously growing demand comes from the automotive industry in order to get an experimental tool allowing for the optimization of materials and sound insulating products implementation inside the car, so as to propose the best acoustic performance at reduced costs. The acoustical imaging system LORHA provides part of the solution and its demonstrated capability of measuring the acoustic field inside a vehicle makes it an advanced tool for performing extensive studies of the acoustic transparency of car openings. This paper focuses on the methodology and recent operational results obtained within the tight collaboration established between METRAVIB RDS, its partner HUTCHINSON and well known car manufacturers.

This work describes the definition and implementation of a dedicated system (hardware and software) for the quantitative evaluation of the anthropometrics and morphological parameters of the back shape. This was applied to the digital 3D analysis of subjects affected by spinal pathologies. In fact in clinical practice it is needed to have a repeatable and easy method to frequent non invasive screening of the rib system records a 3D model of the back shape standard and automated procedure. Its clinical validation is presented.

This SAE Recommended Practice which defines the terms and tabulates the limits of the characteristics for various protective devices used in conjunction with 400-cycle ground power for civil aircraft is intended to assist the airlines in standardizing on 400-cycle protective systems. The limits found to be acceptable in the civil aircraft industry are presented.

This SAE Standard specifies the test methods, dimensions, and requirements for single core 60 V cables intended for use in road vehicle applications where the nominal system voltage ≤60 V DC (25 V AC). It also specifies additional test methods and/or requirements for 600 V cables intended for use in road vehicle applications where the nominal system voltage is >60 V DC (25 V AC) to ≤600 V DC (600 V AC). Where practical, this standard uses ISO 6722 for test methods, dimensions, and requirements. This standard covers ISO conductor sizes which usually differ from SAE conductor sizes. It also covers the individual cores in multicore cables. See ISO 6722 for “Temperature Class Ratings”.

This Standard specifies the test methods, dimensions, and requirements for single-core 60 V cables intended for use in road vehicle applications where the nominal system voltage ≤ 60 V DC (25 V AC). It also specifies additional test methods and/or requirements for 600 V cables intended for use in road vehicle applications where the nominal system voltage is > 60 V DC (25 V AC) to ≤ 600 V DC (600 V AC). Where practical, this standard uses ISO 6722 for test methods, dimensions, and requirements. This standard covers ISO conductor sizes which usually differ from SAE conductor sizes. It also covers the individual cores in multi-core cables. See ISO 6722 for “Temperature Class Ratings”.

The trend of the 2 wheel vehicle obliges to define accurate methodology for analysing each aspect of the vehicle design. The paper will present the definition process of simple, easy to reproduce, cheap tests for the Electric System, and for the components of it, describing the obtainable results. It will be presented which tests are significant, and which variable must acquired, and the method for organizing the data according to the desired study target aim. As example of the System Approach is proposed the analysis of the Electric Generator Power Unit, it will be presented and described the reason why it could be convenient to install a Lundell Generator.

In the design or match process of vehicle powertrain system, gearbox rattle is a common NVH problem which directly affects passengers’ judgment on the quality and performance of vehicle. During the development process of a passenger car, prototype vehicles have serious gear rattle problem. In order to efficiently and fundamentally control this problem, this work first studied the characteristics and mechanisms of the gearbox rattle. The study results revealed that the torsional vibration of powertrain system was the root cause of gearbox rattle. Then a simulation model of the full vehicle was built with the aid of Simulink® toolbox, which is a graphical extension to MATLAB® for modeling and simulation of variety of systems. With this model, the sensitivity analysis and parametrical optimization were performed, and the simulation results indicated that the dual-mass flywheel (DMF) was the best measure to control the rattle.

Nowadays quasi-3D approaches are included in many commercial and research 1D numerical codes, in order to increase their simulation accuracy in presence of complex shape 3D volumes, e.g. plenums and silencers. In particular, these are regarded as valuable approaches for application during the design phase of an engine, for their capability of predicting non-planar waves motion and, on the other hand, for their low requirements in terms of computational runtime. However, the generation of a high-quality quasi-3D computational grid is not always straightforward, especially in case of complex elements, and can be a time-consuming operation, making the quasi-3D tool a less attractive option. In this work, a quasi-3D module has been implemented on the basis of the open-source CFD code OpenFOAM and coupled with the 1D code GASDYN.