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2015-06-16
WIP Standard
J2678
This document provides the rationale used by the Navigation Function Accessibility Subcommittee (the Subcommittee) for the development and content of a SAE J2364 Recommended Practice: Navigation and Route Guidance Function Accessibility While Driving. It provides both the reasoning for the overall recommended practice as well as each of its elements.
2015-06-15
Technical Paper
2015-01-2303
Katherine Tao, Alan Parrett, David Nielubowicz
Abstract The headliner system in a vehicle is an important element in vehicle noise control. In order to predict the performance of the headliner, it is necessary to develop an understanding of the substrate performance, the effect of air gaps, and the contribution from any acoustic pads in the system. Current Statistical Energy Analysis (SEA) models for predicting absorption performance of acoustic absorbers are based on material Biot properties. However, the resources for material Biot property testing are limited and cost is high. In this paper, modeling parameters for the headliner substrate are identified from a set of standard absorption measurements on substrates, using curve fitting and optimization techniques. The parameters are then used together with thickness/design information in a SEA model to predict the vehicle headliner system absorption performance.
2015-06-15
Technical Paper
2015-01-2339
Márcio Calçada, Alan Parrett
Abstract Sound absorption materials can be key elements for mass-efficient vehicle noise control. They are utilized at multiple locations in the interior and one of the most important areas is the roof. At this location, the acoustic treatment typically comprises a headliner and an air gap up to the body sheet metal. The acoustic performance requirement for such a vehicle subsystem is normally a sound absorption curve. Based on headliner geometry and construction, the sound absorption curve shape can be adjusted to increase absorption in certain frequency ranges. In this paper an overall acoustic metric is developed to relate design parameters to an absorption curve shape which results in improved in-vehicle performance. This metric is based on sound absorption coefficient and articulation index. Johnson-Champoux-Allard equivalent fluid model and diffuse field equations are used. The results are validated using impedance tube measurements.
2015-06-15
Technical Paper
2015-01-2210
Quan Wan
Abstract Five parameters are often used in acoustic modeling of porous absorption material, which are air flow resistivity σ, porosity φ, tortuosity α∞, viscous and thermal characteristic lengths Λ and Λ′. These parameters are not easy to be directly tested, especially the latter three parameters. One software capable of identifying inversely these parameters from impedance tube test results becomes increasingly popular. However, its detail stability analysis is rarely reported till now. This paper studies its stability on those porous fiber materials generally applied in vehicle interior trim, such as PET fiber, shoddy, PP/PET mixed fiber. Some conclusions are obtained. (1) The identification of α∞, Λ and Λ′ is always stable when σ and φ are assumed in advance.
2015-06-15
Technical Paper
2015-01-2249
Saad Bennouna, Said Naji, Olivier Cheriaux, Solene Moreau, Boureima Ouedraogo, Jean Michel Ville
Abstract Passengers' thermal comfort inside a car cabin is mainly provided by the Heating, Ventilation and Air Conditioning (HVAC) module. Air provided by HVAC is blown via a blower, passing through different components: flaps, thermal exchangers, ducts… and then distributed to car cabin areas. Interaction between airflow and HVAC components generates noises that emerge in car cabin. Due to this fact, noise is naturally created and its level is linked to flow rate. Valeo is aiming, though CEVAS project, to develop a prediction tool which will provide HVAC spectrum and sound quality data. This tool will be based, in particular, on aeroacoustic measurements using 2N-ports model and Particle Image Velocimetry methods to provide characteristics of HVAC components.
2015-06-15
Technical Paper
2015-01-2235
Arnaud Caillet, Denis Blanchet
Abstract The need in the automotive industry to understand the physical behavior of trims used in a vehicle is high. The PEM (poro-elastic method) was developed to permit an explicit representation of the trims in the FEM full vehicle models and to give tools to diagnose the effect of the trims and test design changes (porous material property, geometry, etc.,). During the last decade, the evolution of software and hardware has allowed the creation of models with highly detailed trim description (porous material using Biot parameters, plastic trims, etc.,). These models can provide good correlation up to 400Hz compared to measurements in contrast to classical NSM (Non Structural Mass) methodology which shows limitations.
2015-06-15
Technical Paper
2015-01-2266
Andrzej Pietrzyk
Abstract Several of the exterior noise sources existing around a vehicle can cause airborne noise issues at relatively low frequencies. SEA, traditionally used for airborne sound issues is not suitable for the frequency range of interest. Finite Element analysis has been used. Handling of the non-reflecting condition on the outer boundary of the exterior cavity is an issue. Recently, advances have been made in several commercially available codes, which made the analysis practical. Including the poro-elastic material model for foam-based carpets is also becoming practically possible. The purpose of the current study is to investigate the practical applications of those new developments against test data, and to estimate the feasibility of using these procedures in the vehicle development projects. Measurements were carried out in a new semi-anechoic chamber at Volvo Cars.
2015-06-15
Technical Paper
2015-01-2271
Yong Du Jun, Bong Hyun Park, Kang Seok Seo, Tae Hyun Kim, Myoung Jae Chae
Abstract Modern automotive seats require improvements in their design, safety, comfort including sitting and riding comfort. Among those, seat comfort is known to be difficult to evaluate because the comfort is a human feeling. As an approach to evaluate the human comfort in an objective manner, an objective measure is proposed for seat riding comfort evaluation under low frequency vibratory conditions which represents typical roll and pitch motions of driving motor vehicles. The related feeling due to this low frequency vehicle motion is termed ‘hold feeling’ because the seated body may tend to deviate from the defined seating position under such vehicle motion input. Dynamic pressure measurements have been conducted in the frequency range up to 1.0 Hz to monitor the interface pressure change behavior of the seat-subject body.
2015-06-15
Technical Paper
2015-01-2273
Curtis Jones, Zhengyu Liu, Suhas Venkatappa, James Hurd
Abstract This paper presents the methodology of predicting vehicle level automotive air-handling system air-rush noise sound quality (SQ) using the sub-system level measurement. Measurement setup in both vehicle level and sub-system levels are described. To assess the air-rush noise SQ, both 1/3 octave band sound pressure level (SPL) and overall Zwicker's loudness are used. The “Sound Quality Correlation Functions (SQCF)” between sub-system level and vehicle level are developed for the specified climate control modes and vehicle segment defined by J.D. Power & Associates, while the Zwicker's loudness is calculated using the un-weighted predicted 1/3 octave band SPL. The predicting models are demonstrated in very good agreement with the measured data. The methodology is applied to the development of sub-system SQ requirement for upfront delivery of the optimum design to meet global customer satisfaction
2015-06-15
Journal Article
2015-01-2276
Zhengyu Liu, Donald Wozniak, Manfred Koberstein, Curtis Jones, Jan Xu, Suhas Venkatappa
Abstract Refrigerant flow-induced gurgling noise is perceived in automotive refrigerant systems. In this study, the condition of the gurgling generation is investigated at the vehicle level and the fundamental root cause is identified as the two-phase refrigerant flow entering the TXV for system equipped with variable displacement compressors. By conducting literature reviews, the acoustic characteristics of the flow patterns and the parameters affecting the flow regimes in horizontal and vertical tubes are summarized. Then the gurgling mechanism is explained as the intermittent flow is developed at the evaporator inlet. In the end, the improved and feasible design for avoiding the intermittent flow (slug, plug or churn flow) or minimizing its formation is proposed and verified in refrigerant subsystem (RSS) level. Finally, the guidelines for the attenuation and suppression of the gurgle are provided.
2015-06-15
Journal Article
2015-01-2275
Manfred Koberstein, Zhengyu Liu, Curtis Jones, Suhas Venkatappa
Abstract In the thermal expansion valve (TXV) refrigerant system, transient high-pitched whistle around 6.18 kHz is often perceived following air-conditioning (A/C) compressor engagements when driving at higher vehicle speed or during vehicle acceleration, especially when system equipped with the high-efficiency compressor or variable displacement compressor. The objectives of this paper are to conduct the noise source identification, investigate the key factors affecting the whistle excitation, and understand the mechanism of the whistle generation. The mechanism is hypothesized that the whistle is generated from the flow/acoustic excitation of the turbulent flow past the shallow cavity, reinforced by the acoustic/structural coupling between the tube structural and the transverse acoustic modes, and then transmitted to evaporator. To verify the mechanism, the transverse acoustic mode frequency is calculated and it is coincided to the one from measurement.
2015-06-15
Journal Article
2015-01-2323
Abdelhakim Aissaoui, Ravindra S Tupake, Vilas Bijwe, Mohammed Meskine, Franck Perot, Alain Belanger, Rohit J Vaidya
For the automotive industry, acoustic comfort is of increasing importance. The market and customer expectation make the HVAC system noise quality a question to be addressed as early as possible in the vehicle development process. On one hand, the so-called traditional sources of annoyance such as engine, road-tires contact, exhaust systems and wind-noise have been significantly reduced for most traditional combustion engine vehicles. On the other hand, considered in the past as secondary noise sources, HVAC systems become the main sources for hybrid and electric and Stop-start vehicles. Previous studies have demonstrated the ability of a CFD/CAA approach based on the Lattice Boltzmann Method (LBM) to predict HVAC system noise including real and complex ducts, registers, mixing unit and blower geometries.
2015-06-10
WIP Standard
J2914
This document provides an overview on how and why EGR coolers are utilized, defines commonly used nomenclature, discusses design issues and trade-offs, and identifies common failure modes. The reintroduction of exhaust gas into the combustion chamber is just one component of the emission control strategy for internal combustion (IC) engines, both diesel and gasoline, and is useful in reducing exhaust port emission of Nitrogen Oxides (NOx). Other means of reducing NOx exhaust port emissions are briefly mentioned, but beyond the scope of this document.
2015-06-09
Article
Hand gesture transfer of information from the center console screen to the head-up display or gauge cluster display is a featured capability shown in a demonstration vehicle.
2015-06-09
Article
Touch screens have become a common interface between drivers and their vehicle. But touch screens can also be distracting. In this episode of SAE Eye on Engineering, Senior Editor Lindsay Brooke looks at Continental Automotive's new haptic feedback display.
2015-06-04
Article
The company has put its first complete touch display with haptic feedback into demonstrator vehicles as a prelude to production. The unit is a touch-sensitive 8-in flat screen with an integrated haptic actuator system.
2015-06-04
Article
Motorists may soon be able to point the headlamps of their cars with just their eyes to see better at night.
2015-06-04
Standard
J2802_201506
This document specifies the minimum recommendations for Blind Spot Monitoring System (BSMS) operational characteristics and elements of the user interface. A visual BSMS indicator is recommended. BSMS detects and conveys to the driver via a visual indicator the presence of a target (e.g., a vehicle), adjacent to the subject vehicle in the “traditional” Adjacent Blind Spot Zone (ABSZ). The BSMS is not intended to replace the need for interior and exterior rear-view mirrors or to reduce mirror size. BSMS is only intended as a supplement to these mirrors and will not take any automatic vehicle control action to prevent possible collisions. While the BSMS will assist drivers in detecting the presence of vehicles in their ABSZ, the absence of a visual indicator will not guarantee that the driver can safely make a lane change maneuver (e.g., vehicles may be approaching rapidly outside the ABSZ area).
2015-06-04
Standard
J2988_201506
The scope of this document is a technology-neutral approach to speech input and audible output system guidelines applicable for OEM and aftermarket systems in light vehicles. These may be stand-alone interfaces or the speech aspects of multi-modal interfaces. This document does not apply to speech input and audible output systems used to interact with automation or automated driving systems in vehicles that are equipped with such systems while they are in use (ref. J3016:JAN2014).
2015-06-02
Standard
AIR1069B
Determine the required minimum oxygen concentration to be breathed prior to, during, and after a loss of cabin pressurization, and determine recommended means necessary to provide the required oxygen concentrations.
2015-05-29
Standard
ARP986D
This SAE Aerospace Recommended Practice (ARP) defines recommended analysis and test procedures for qualification of pneumatically, electrically, manually, and hydraulically actuated air valves. They may be further defined as valves that function in response to externally applied forces or in response to variations in upstream and/or downstream duct air conditions in order to maintain a calibrated duct air condition (e.g., air flow, air pressure, air temperature, air pressure ratio, or air shutoff). Qualification testing performed on the airplane to verify compatibility of the valve function and stability as part of a complete system is outside the scope of this document. Refer to ARP1270 for design and certification requirements for cabin pressurization control system components. As this document is only a guide, it does not supersede or relieve any requirements contained in detailed Customer specifications.
2015-05-27
Article
A second coolant loop in a Fiat Grande Punto prototype provides liquid cooling of the A/C condenser and turbo intercooler, with potential for including air coolers for engine and transmission oil, power steering fluid and other heat exchangers. Engineers measured a 5% improvement in fuel economy during A/C-on operation during NEDC testing.
2015-05-08
WIP Standard
J2365
This SAE Recommended Practice applies to both Original Equipment Manufacturer (OEM) and aftermarket route-guidance and navigation system functions for passenger vehicles. This recommended practice provides a method for calculating the time required to complete navigation system-related tasks. These estimates may be used as an aid to assess the safety and usability of alternative navigation and route guidance system interfaces to assist in their design. This document does not consider voice-activated controls, voice output from the navigation system, communication between the driver and others, or passenger operation.
2015-05-07
Standard
ARP4156C
This document defines the method for voltage identification by the use of color-coded insulators at the base of the lamps. Table 1 shows the design volts and corresponding insulator colors. The part numbers shown are for example purposes only, as an option. Insulator colors are to be easily distinguishable as green, yellow, red, and white. Additional colors may be added by a revision process as required.
2015-05-07
Standard
J2842_201505
The intent of this standard is to establish a framework to assure that all evaporators for R-744, R-1234yf, and R-445A mobile air conditioning (MAC) systems meet appropriate testing and labeling requirements. SAE J639 requires vehicle manufacturers to perform assessments to minimize reasonable risks in production MAC systems. The evaporator (as designed and manufactured) shall be part of that risk assessment and it is the responsibility of the vehicle manufacturer to assure all relevant aspects of the evaporator are included. It is the responsibility of all vehicle or evaporator manufacturers to comply with the standards of this document at a minimum. (Substitution of specific test procedures by vehicle manufactures that correlate well to field return data is acceptable.) As appropriate, this standard can be used as a guide to support risk assessments.
2015-05-07
Standard
J1757/1_201505
The scope of this SAE Standard is to provide methods to determine display optical performance in all typical automotive ambient light illumination - with focus on High Ambient Contrast Ratio, which is critical for display legibility in a sunshine environment. It covers indoor measurements and simulated outdoor lighting. It is not the scope of this document to set threshold values for automotive compliance. However some recommended values are presented for reference.
2015-05-05
WIP Standard
J3099
Presents the seating accommodation model used to determine seat track length for accommodation in design.
2015-05-04
WIP Standard
J576
This SAE Recommended Practice provides test methods and requirements to evaluate the suitability of plastic materials intended for optical applications in motor vehicles. The tests are intended to determine physical and optical characteristics of the material only. Performance expectations of finished assemblies, including plastic components, are to be based on tests for lighting devices, as specified in SAE Standards and Recommended Practices for motor vehicle lighting equipment. Field experience has shown that plastic materials meeting the requirements of this document and molded in accordance with good molding practices will produce durable lighting devices.
2015-05-01
Journal Article
2015-01-9017
Johannes Wurm, Matthias Fitl, Michael Gumpesberger, Esa Väisänen, Christoph Hochenauer
Abstract Nowadays, investigating underhood airflow by using numerical simulation is a standard task in the development process of passenger cars and commercial vehicles. Numerous publications exist which deal with simulating the airflow through the engine compartment of road vehicles. However, hardly anything can be found which deals with off-road vehicles and nothing exists which focuses on snowmobiles. In the presented paper the airflow and the thermal conditions inside the engine compartment of a snowmobile are investigated by the usage of computational fluid dynamics (CFD) as well as experimental methods. Field tests at arctic conditions have been conducted on a serial snowmobile to measure temperatures inside the compartment and to gain realistic boundary conditions for the numerical simulation. Thermocouples (type K) were attached under the hood to measure exhaust, air, coolant and surface temperatures of several components at previously defined load cases.
2015-05-01
Magazine
Unmanned Aerial Systems Deploying Next-Generation UAS Platforms with 3U VPX Unmanned Ground Vehicles UGVs - On the Cutting Edge of Thermal Management Unmanned Surface/Underwater Vehicles Controlling the Seas - Introducing a New Concept in Autonomous Surface/Underwater Vehicles Robotics Connectivity in Robotic Systems
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