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Journal Article

Connected Car Architecture and Virtualization

2016-04-05
2016-01-0081
Connectivity has become an essential need for daily device users. With the car projected to be the “ultimate mobile device”, connectivity modules will eventually be mainstream in every car. Network providers are expanding their infrastructure and technology to accommodate the connected cars. Besides making voice and emergency calls the connected car will be sharing data with telematics service providers, back end systems and other vehicles. This trend will increase vehicle modules, complexity, entry points and vulnerabilities. This paper will present the current connected car architectures. The paper will present current architectural issues of the connected car and its vulnerabilities. The paper will present a new proposed architecture for the future connected car that enhances efficiency and security.
Technical Paper

Test Strategy for Linux based Platforms using Open Source Tools

2016-04-05
2016-01-0053
Today open source software is widely used in different domains like Desktop systems, Consumer electronics (smart phones, TV, washing machines, camera, printers, smart watches), Automotive, Automation etc. With the increased involvement of the open source software in the different domains including the safety critical ones, there has been a requirement of the well-defined test strategy to test and verify such systems. Currently there are multiple open source tools and frameworks to choose from. The paper describes the various open source test strategies and tools available to qualify such systems, their features, maintenance, community support, advantages and disadvantages. Target audience would be the software engineers, program managers, using an open source stack for the product development.
Technical Paper

Key Aspects of Electronics Automotive Components Testing

2013-10-07
2013-36-0569
Electronics components are estimated to be between 9 to 15 % of a total vehicle cost, and this trend will remain strong for the next years. The amount of electronics content in a vehicle has grown steadily since 1970's, and as a result, development challenges such as testing and validation are a key aspect of its overall development costs. Testing costs can amount easily to US$ 500 k in medium complex automotive parts of a vehicle (e.g. instrument cluster) depending on a specific OEM customer demand, and this on top of limited regional laboratory capacity can also lead to increased testing time. The goal of this paper is to outline key aspects of electronics in vehicle components testing, including overall costs and timing, and propose a lean approach to optimize such costs & timing. The key aspects of such optimization include not only resources, but also laboratories and upfront OEM customer planning.
Journal Article

Assessment of Automatic Volume Leveling for Automotive Sound Systems

2013-04-08
2013-01-0162
This paper presents an assessment of competing algorithms for normalizing volume levels between tracks and/or sources in an automotive infotainment system. Portable media players such as smartphones and iPod® devices are extremely popular for listening to music collections or streaming content from the Internet. The lack of normalization is a source of dissatisfaction if the user experiences significant changes in audio level between tracks. Several commercially available algorithms exist to solve this problem. This research includes a double-blind listening test comparing an audio sample processed with the different leveling algorithms to an unprocessed reference. The listener preference rating is recorded and results indicate which algorithm is preferred.
Journal Article

Ensuring Audio Signal Quality in Automotive Infotainment Systems

2013-04-08
2013-01-0163
In automotive infotainment systems, multiple types of digital audio signals are usually present. Some come from internal sources, such as a CD or USB stick, and some come from external sources, such as an internet stream or digital radio. These sources usually have different sample-rates, and may also be different from one or more system sample-rates. Managing and transporting these signals throughout the system over different sample-rate domains require detailed upfront architecture analysis and correct system design to ensure signal quality is maintained to the desired level. Incorrect design can add significant user-perceivable noise and distortion. This paper examines the key analysis factors, the effects of poor design and the approaches for achieving robust signal handling and ensuring desired signal quality.
Journal Article

A New Automotive Air Conditioning System Simulation Tool Developed in MATLAB/Simulink

2013-04-08
2013-01-0850
Accurate evaluation of vehicles' transient total power requirement helps achieving further improvements in vehicle fuel efficiency. When operated, the air-conditioning (A/C) system is the largest auxiliary load on a vehicle, therefore accurate evaluation of the load it places on the vehicle's engine and/or energy storage system is especially important. Vehicle simulation models, such as "Autonomie," have been used by OEMs to evaluate vehicles' energy performance. However, the load from the A/C system on the engine or on the energy storage system has not always been modeled in sufficient detail. A transient A/C simulation tool incorporated into vehicle simulation models would also provide a tool for developing more efficient A/C systems through a thorough consideration of the transient A/C system performance. The dynamic system simulation software MATLAB/Simulink® is frequently used by vehicle controls engineers to develop new and more efficient vehicle energy system controls.
Journal Article

Quality Inspection of Spot Welds using Digital Shearography

2012-04-16
2012-01-0182
Spot Welding is an important welding technique which is widely used in automotive and aerospace industry. One of the keys of checking the quality of the welds is measuring the size of the nugget. In this paper, the Shearographic technique is utilized to test weld joint samples under the thermal loading condition. The goal is to identify the different group of the nuggets (i.e. small, middle, and large sizes, which indicate the quality of spot welds). In the experiments, the sample under test is fixed by a magnet method from behind at the four edges. Thermal loading was applied in the back side and the sample is inspected using the digital Shearographic system in the front side. Results show the great possibility of classifying the nugget size into three groups and the measurement is well repeatable.
Technical Paper

Statistical Modeling of Fatigue Crack Growth in Wing Skin Fastener Holes

2012-04-16
2012-01-0482
Estimation and prediction of residual life and reliability are serious concerns in life cycle management for aging structures. Laboratory testing replicating fatigue loading for a typical military aircraft wing skin was undertaken. Specimens were tested until their fatigue life expended reached 100% of the component fatigue life. Then, scanning electron microscopy was used to quantify the size and location of fatigue cracks within the high stress regions of simulated fastener holes. Distributions for crack size, nearest neighbor distances, and spatial location were characterized statistically in order to estimate residual life and to provide input for life cycle management. Insights into crack initiation and growth are also provided.
Technical Paper

Assessment Metric Identification and Evaluation for Side Airbag (SAB) Development

2011-04-12
2011-01-0257
This paper discusses steps for identifying, evaluating and recommending a quantifiable design metric or metrics for Side Airbag (SAB) development. Three functionally related and desirable attributes of a SAB are assumed at the onset, namely, effective SAB coverage, load distribution and efficient energy management at a controlled force level. The third attribute however contradicts the “banana shaped” force-displacement response that characterizes the ineffective energy management reality of most production SAB. In this study, an estimated ATD to SAB interaction energy is used to size and recommend desired force-deformation characteristic of a robust energy management SAB. The study was conducted in the following three phases and corresponding objectives: Phase 1 is a SAB assessment metric identification and estimation, using a uniform block attached to a horizontal impact machine.
Technical Paper

Human Factors Flight Test Evaluation of an Airport Surface Display with Indications & Alerts (SURF IA)

2010-09-30
2010-01-1663
This paper presents the results of a human factors flight test evaluation of a display of Enhanced Traffic Situational Awareness on the Airport Surface with Indications and Alerts (SURF IA). The study is an element of the FAA-sponsored Surface Conflict Detection and Alerting with Consideration of Arrival Applications program. The objective of the flight test was to conduct a comparative evaluation of two candidate SURF IA displays: a detailed Airport Surface Situation Awareness (ASSA) display and a runways-only Final Approach Runway Occupancy Awareness (FAROA) display. Six pilots with a current Air Transport Pilot Certificate each completed 18 scenarios. A Beechcraft King Air C-90 and a Cessna Citation Sovereign aircraft were deployed for the flight tests. The scenarios were conducted at Seattle-Tacoma International Airport and at Snohomish County Paine Field Airport, with each aircraft acting as ‘traffic’ for the other aircraft.
Technical Paper

Improving Load Regeneration Capability of an Aircraft

2009-11-10
2009-01-3189
This paper presents new concepts for improving management of the electrical load power regeneration of an aircraft. A novel electrical system that allows for load regeneration back to the distribution bus is described. This approach offers the benefits of reduced weight, volume, and cost, as well as improved reliability. Also described is an electrical machine control mechanism that creates motor power to run the prime mover (i.e., the main engine to dissipate the regenerated power). Instead of main engine generation, this approach can be applied to an auxiliary power unit (APU) or power and thermal management system (PTMS). Background information regarding the regeneration concept is presented. The concept definition and the various modes of operation of the improved system are analyzed and described in detail. Results from the dynamic simulation of the system model are included.
Technical Paper

Photometric and Colorimetric Measurement Procedures for Airborne Electronic Flat Panel Displays — SAE ARP 4260

2009-11-10
2009-01-3143
SAE ARP 4260 Photometric and Colorimetric Measurement Procedures for Airborne Electronic Flat Panel Displays [1] has recently been revised. This new revision reaffirms that ARP 4260 is pertinent to the aviation industry, changes the content to keep up with the state of the art, and adds clarification where needed. ARP 4260 contains methods used to measure the optical performance of airborne electronic flat panel display systems and is referenced in SAE ARP 4256, Design Objectives for Liquid Crystal Displays for Part 25 (Transport) Aircraft [2] and in SAE AS 8034, Minimum Performance Standard for Airborne Multipurpose Electronic Displays [3].
Technical Paper

Cascade Distillation Subsystem Development: Progress Toward a Distillation Comparison Test

2009-07-12
2009-01-2401
Recovery of potable water from wastewater is essential to the success of long-duration human missions to the moon and Mars. Honeywell International and a team from the NASA Johnson Space Center (JSC) are developing a wastewater processing subsystem that is based on centrifugal vacuum distillation. The wastewater processor, which is referred to as the cascade distillation subsystem (CDS), uses an efficient multistage thermodynamic process to produce purified water. A CDS unit employing a five-stage distiller engine was designed, built, and delivered to the NASA JSC Advanced Water Recovery Systems Development Facility for performance testing; an initial round of testing was completed in fiscal year 2008 (FY08). Based, in part, on FY08 testing, the system is now in development to support an Exploration Life Support Project distillation comparison test that is expected to begin in 2009.
Journal Article

Developing Safety Standards for FCVs and Hydrogen Vehicles

2009-04-20
2009-01-0011
The SAE Fuel Cell Vehicle (FCV) Safety Working Group has been addressing FCV safety for over 9 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable as a Recommended Practice for FCV development with regard to the identification of hazards and the definition of countermeasures to mitigate these hazards such that FCVs can be operated in the same manner as conventional gasoline internal combustion engine (ICE)-powered vehicles. SAE J2578 is currently being revised so that it will continue to be relevant as FCV development moves forward. For example, test methods were refined to verify the acceptability of hydrogen discharges when parking in residential garages and commercial structures and after crash tests prescribed by government regulation, and electrical requirements were updated to reflect the complexities of modern electrical circuits which interconnect both AC and DC circuits to improve efficiency and reduce cost.
Journal Article

The Effects of Detailed Tire Geometry on Automobile Aerodynamics - a CFD Correlation Study in Static Conditions

2009-04-20
2009-01-0777
A correlation study was performed between static wind tunnel testing and computational fluid dynamics (CFD) for a small hatchback vehicle, with the intent of evaluating a variety of different wheel and tire designs for aerodynamic forces. This was the first step of a broader study to develop a tool for assessing wheel and tire designs with real world (rolling road) conditions. It was discovered that better correlation could be achieved when actual tire scan data was used versus traditional smooth (CAD) tire geometry. This paper details the process involved in achieving the best correlation of the CFD prediction with experimental results, and describes the steps taken to include the most accurate geometry possible, including photogrammetry scans of an actual tire that was tested, and the level of meshing detail utilized to capture the fluid effects of the tire detail.
Technical Paper

Development of an Engineering Analysis Tool for Time-Temperature Analysis of Automotive Components

2009-04-20
2009-01-1179
This paper describes the development of an engineering analysis tool that assesses the life of vehicle components, after exposure to heat. As a standard engineering practice, each component or part of a component has a “long term” and a “short term” temperature goal based on the part’s material physical properties. At higher temperatures, component’s physical properties degrade at a faster rate, and the component’s useful life can be significantly reduced. The extent of degradation depends upon the duration of exposure, the magnitude of the over-temperature and rate of thermal degradation. This tool utilizes actual vehicle test data from test cells or road testing, material physical properties, and expected vehicle duty cycle to determine the expected component life. When component temperature goals are exceeded, the software calculates the total duration of time above the goal temperature.
Technical Paper

Application of Kinetics of Thermal Degradation for Time-Temperature Analysis of Automotive Components

2009-04-20
2009-01-1178
A fundamental problem in the development of automotive thermal protection strategies is the understanding of the effect of time and temperature on vehicle components life and their performance throughout the life of the vehicle. Due to restrictions on emissions and the stringent requirements for improved fuel economy, the use of polymers and synthetic materials has been widely adopted in automotive applications. It is therefore critical to develop a process to estimate life of engineering materials based on thermal testing and material physical properties. While a series of carefully selected vehicle tests can determine components temperatures during different testing conditions, a need still exists to determine the expected component life and performance throughout the life of the vehicle. Kinetic models have been widely used, in literature, to determine the aging of polymeric and composite materials over time.
Technical Paper

Blind Spot Monitoring by a Single Camera

2009-04-20
2009-01-1291
A practical and low cost Blind Spot Monitoring system is proposed. By using a single camera, the range and azimuth position of a vehicle in a blind spot are measured. The algorithm is based on the proposed RWA (Range Window Algorithm). The camera is installed on the door mirror and monitoring the side and rear of the host vehicle. The algorithm processes the image and identifies range and azimuth angle of the vehicle in the adjacent lane. This algorithm is applied to real situations. The 388 images including several kinds of vehicles are analyzed. The detection rate is 86% and the range accuracy is 1.6[m]. The maximum detection range is about 30[m].
Technical Paper

A Method for Obtaining Optimum Fuel Economy Performance using Transient Combustion Measurements

2009-04-20
2009-01-0243
An experiment was conducted testing a powertrain package consisting of a four cylinder four valve engine coupled to a four speed automatic transmission in a dynamometer test cell. Cylinder pressure transducers, an encoder, and other instrumentation were used to measure transient combustion events. The transient cycle chosen for testing was a Cold 80 of the Federal Test Procedure (FTP) that produces a standardized fuel economy value. After analyzing the combustion events, a determination was made between the spark advance delivered and a revised spark advance for optimum combustion efficiency. Based upon the relationship between spark advance and fuel consumption, a prediction for the improved fuel consumption was made. The testing was then repeated to evaluate the revised spark advance and the fuel economy benefits in comparison to the predicted values.
Technical Paper

Numerical Simulation of a Direct-Injection Spark-Ignition Engine with Different Fuels

2009-04-20
2009-01-0325
This paper focuses on the numerical investigation of the mixing and combustion of ethanol and gasoline in a single-cylinder 3-valve direct-injection spark-ignition engine. The numerical simulations are conducted with the KIVA code with global reaction models. However, an ignition delay model mitigates some of the deficiencies of the global one-step reaction model and is implemented via a two-dimensional look-up table, which was created using available detailed kinetics models. Simulations demonstrate the problems faced by ethanol operated engines and indicate that some of the strategies used for emission control and downsizing of gasoline engines can be employed for enhancing the combustion efficiency of ethanol operated engines.
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