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Vehicle audio system performance is an important attribute for final costumers. In this sense, its evaluation is an important aspect for selecting the design and validation process for automobile manufacturers. Usually the vehicle audio system performance is evaluated only by subjective judgment. However the design requirements demands objective measurements to set targets establish benchmarking and apply refinements to the design. Thus, in order to evaluate and improve sound system performance, it has been established a subjective evaluation process on reproducing and analyzing customer perception in a more reliable way. To support this information, objective evaluations have been used based on total harmonic distortion (THD), normalized frequency response (NFR) methods and spectrogram, which have been shown as straight and fast objective tools. Reinforcing the objective evaluations, qualitative time-frequency spectrogram has been used.

Recently a sound absorption study was undertaken involving a wide range of samples of common automotive materials from ten different manufacturers. The study included 128 porous absorbers of varying thicknesses and material types (cotton blends, microfibers, etc.). This paper presents the results of that study. It was found that no single material outperformed all the others; rather, metrics such as specific air flow resistance were more important than the specific material making up the absorber. In general, samples within a certain range of thickness and specific air flow resistance showed the best performance. However, there was no single value of specific flow resistance that was optimal for all material thicknesses. Instead thinner materials required higher flow resistivity than thicker materials. In addition, because the specific air flow resistance is such an important parameter, the presence or lack of a scrim had a significant impact on absorption results.

This paper takes a look at one of the problems associated with the concept of autonomous control of vehicles in the current traffic environment, namely the changing of lanes. Given the increase in traffic density on highways and interstate roads over the past few decades, safe navigation of individual vehicles has required increased driver attention and diligence to an increased number of visual information cues. The concept of autonomous vehicles operating without driver intervention in the present traffic system appears daunting. One aspect of traffic maneuvering involves changing lanes to a position between two other vehicles. Although this aspect appears straightforward, it is the lack of accurate knowledge of other vehicle maneuvering which makes the task difficult. Using Model Predictive Control (MPC) techniques, the task is addressed in an optimization problem framework.

Considering that the most part of commercial vehicles are equipped with air brakes it is very important assure specific technical requirements for air brake system and its components. In addition, the effects of brake system failure are more critical for commercial vehicles which require more attention on their requirements details. Historically, the development of air brakes technology started on North America and Europe and consequently two strong and distinct resolutions were structured: FMVSS 121 and ECE R.13, respectively. For passenger cars were developed the ECER.13H to harmonize North American and European resolutions. However, for commercial vehicles regional applications, culture and implementation time must be considered. These commercial vehicles peculiarities must be understood and their specific requirements harmonized to attend the global marketing growth.

It is very important and unquestionable that we need to have a clear technical requirement for Air Brake Systems and its components, since it is one of most important regarding safety. Looking to heavy commercial vehicles and possible air brake system failures, everything becomes clearly to pay total attention for these normative and regulatory requirements. Historically, the development of Brakes technology has started on EUA and Europe and consequently two strong and distinct requirements were structured: FMVSS 121 and ECE-R13. From decades people are trying to harmonize these requirements and for passenger cars, the evolution was faster. However, for commercial vehicles there are more peculiarities considering regional applications and some of them cultural and implementation time. As globally market is growing so fast as well new markets around the world, become fundamental the clearly understanding of these similarities, variants, peculiarities and correlated requirements.

The growing competition of the automotive market makes more and more necessary the reduction of development time and consequently, the increase of the capacity to quickly respond to the launching of the competitors. One of the most costly phases on the vehicle development process is the field durability test, both in function of the number of prototypes employed and the time needed to its execution. More and more diffused, the fatigue life prediction methods have played an important part in the durability analysis via CAE. Nevertheless, in order they can be reliable and really being able to reduce the development time and cost, they need to be provided with load cases that can accurately represent the field durability tests. This work presents a CAE approach used for light trucks in order to get a reasonable understanding of component durability behavior due to payload increase. In general, road load data is not available for a new payload condition.

The following paper will discuss the latest developments that are taking place in the automobile industry pertaining to the development of a high-speed data bus standard. By 2005, it is likely that we will see the introduction of numerous high-speed, real time multimedia applications proliferating into the vehicle. These applications will provide the car owner access to information, entertainment, communication, and safety as well as the Internet. These systems will also drive the need to have a high-speed data bus serving as a backbone for data traffic between different applications. Currently, the minimum bus speed being considered for such applications is 100 Mbps, which is suitable for transmitting a compressed video and audio data stream. Concerns about electromagnetic interference (EMI) and weight have driven the physical media requirement to be plastic optical fiber (POF).

Design for Six Sigma has been applied successfully in many industries, but industry differences present challenges that influence implementation. Implementers in the automotive industry face the challenge of integrating DFSS into mature and complex product development systems. This requires a clear definition of the DFSS role in an organization and clear guidelines for project scope. But effective definitions and guidelines will vary depending on an organization's place in the supply chain. In addition, varying levels of project scope present challenges in determining effective metrics. Organizations are best served by a flexible set of metrics that drive the right behavior at all organizational levels. Once roles and metrics are established, balancing DFSS with other ongoing programs becomes a challenge. Over time, the elements of DFSS should be integrated into a holistic system that produces high quality, market-winning products.

Aluminum extrusions are used in the automotive industry for body structure applications requiring cross-section design flexibility, high section stiffness, and high strength. Heat-treatable 6xxx series extrusion alloys have typically been used in automotive due to commercial availability, competitive cost, high strength, and impact performance. This paper presents a characterization study of mechanical properties of 6xxx series aluminum extrusions using digital image correlation (DIC). DIC has been used to capture spatial strain distribution and its evolution in time during material deformation. The materials of study were seamless and structural 6061 and 6082 extrusions. The alloys have been tensile tested using an MTS load frame with a dual optical camera system to capture the stereoscopic digital images. Notable results include the differing anisotropy of seamless and structural extrusions, as well as the influence of artificial aging on anisotropy.

High frequency variations in crankcase pressure have been observed in Inline-four cylinder (I4) engines and an understanding of the causes, frequency and magnitude of these variations is helpful in the design and effective operation of various engine systems. This paper shows through a review and explanation of the physics related to engine operation followed by comparison to measured vehicle data, the relationship between crankcase volume throughout the engine cycle and the observed pressure fluctuations. It is demonstrated that for a known or proposed engine design, through knowledge of the key engine design parameters, the frequency and amplitude of the cyclic variation in crankcase pressure can be predicted and thus utilized in the design of other engine systems.

Over the past decades, Computer Aided Engineering (CAE) based assessment of vehicle durability, NVH (Noise, Vibration and Harshness) and crash performance has become very essential in vehicle development and verification process. CAE activity is often organized as different groups based on the specific attributes (durability, NVH and crash). Main reasons for this are the expertise required and the difference in the finite element software technologies (explicit vs implicit) used to perform and interpret various CAE analyses in each of the attributes. This leads to individual attribute team creating its own model of the vehicle and there is not much exchange of the CAE models between the attribute teams. Different model requirements for each attribute make model sharing challenging. However, CAE analyses for all attributes start with common CAD and follow the same sub-process in vehicle development cycle.

Analysis of road accidents has shown that an important portion of fatal crashes involving Commercial Vehicles are caused by rollovers. ESC systems in Commercial Vehicles can reduce rollovers, severe understeer or oversteer conditions and minimize occurrences of jackknifing events. Several studies have estimated that this positive effect of ESC on road safety is substantial. In Europe, Electronic Stability Control (ESC) is expected to prevent by far the most fatalities and injuries: about 3,000 fatalities (-14%), and about 50,000 injuries (-6%) per year. In Europe, Electronic Stability Control Systems is mandatory for all vehicles (since Nov. 1st, 2011 for new types of vehicle and Nov. 1st, 2014 for all new vehicles), including Commercial Vehicles, Buses, Trucks and Trailers.

In automotive industry, the interior quietness is a task that manufacturers are constantly improving for passenger comfort. In order to improve the interior quietness there are considered the contribution of structure borne and airborne noise. An alternator used in vehicles for generation of electricity can be considered as a contributor of airborne noise. Due to the characteristics of an alternator, it could radiate mechanical, aerodynamic and electromagnetic noise. The last two characteristics are normally perceived by customer during powertrain and idle evaluation. In this paper is presented correlation between interior noise measured on road test and alternator radiated noise measured on bench test.

For the past seven years, the Ford Motor Company has been working on the development of catalytic exhaust treating systems designed to minimize the emission of certain vehicle exhaust gas constituents. In 1959, the development of a low-temperature, catalytic-converter system for the oxidation of exhaust gas hydrocarbons was described in a paper presented to the SAE. That system, which used vanadium pentoxide as the catalyst, has since been extensively developed in a program that included 250,000 miles of converter evaluation on vehicles. Many of the basic system requirements and problems covered in those tests are relevant in vehicle applications of a catalytic converter system with any type of catalyst. With the insertion of a carbon monoxide limit in the California Exhaust Standard, work on the low-temperature, catalytic converter system was discontinued since this system did not, and was not designed to, oxidize carbon monoxide.

As systems necessarily become more integrated and increasingly complex through market demands for more features, technical risks and therefore business risks increase. It becomes correspondingly harder to show that the properties desired of these Systems of Systems (SoS) actually hold under normal or abnormal operation. In particular, it is hard to detect emergent properties of a SoS because properties of individual systems are not necessarily compositional, especially during failure. This paper describes the objectives of a project addressing the problem of Dependable System of Systems and other related research in the field of Automotive Electronics. The capability being developed is based upon the scalable ‘Assumption-Commitment’[1] paradigm so that it can be applied to large and complex systems of systems.

As part of a continuous research and innovation effort, Ford Motor Company has been evaluating hydrogen as an alternative fuel option for vehicles with internal combustion engines since 1997. Ford has recently designed and built an Econoline (E-450) shuttle bus with a 6.8L Triton engine that uses gaseous hydrogen fuel. Safe practices in the production, storage, distribution, and use of hydrogen are essential for the widespread public and commercial acceptance of hydrogen vehicles. Hazards and risks inherent in the application of hydrogen fuel to internal combustion engine vehicles are explained. The development of a Hydrogen Management System (H2MS) to detect hydrogen leaks in the vehicle is discussed, including the evolution of the H2MS design from exploration and quantification of risks, to implementation and validation of a working system on a vehicle. System elements for detection, mitigation, and warning are examined.

New supplier / manufacturer relationship are necessary to produce products quickly, cost-effectively, and with features expected by the customer. However, the need for a new relationship is not universally accepted and endorsed. Resistance can be minimized through supplier self-assessment (such as Ford Motor Company's web-based instruments), management initiatives, and incentives. Trust and sharing are hallmarks. This strategy requires a new workplace paradigm affecting culture and people issues. Teams, extend across companies, share ideas and innovations. Decisions need to be mutually beneficial and the long-term value, for supplier and manufacturer, needs to be considered.

Throughout the evolution of transportation technology the automotive industry has continually devised methods of diagnosing and servicing vehicle electrical and electronic concerns. Methodologies have always included special test equipment accompanied by volumes of printed manual procedures. Today's vehicle technology, with its highly interactive/integrated systems control capability, has brought on a new level of complexity and confusion to the service technician. In order to assist the technician in the diagnosis of microprocessor based control systems, the service industry has developed highly sophisticated on-board vehicle diagnostics as well as off-board computer based equipment. This paper describes the progression of service test equipment provided by Ford Motor Company to assist in vehicle electrical/electronic diagnostics. Similar to all industry manufacturers Ford Motor has devised both on-board and off-board systems which are required to fix the car right the first time.

Numerical analyses frequently accompany experimental investigations that study injury biomechanics and improvements in automotive safety. Limited by computational speed, earlier mathematical models tended to simplify the system under study so that a set of differential equations could be written and solved. Advances in computing technology and analysis software have enabled the development of many sophisticated models that have the potential to provide a more comprehensive understanding of human impact response, injury mechanisms, and tolerance. In this article, 50 years of publications on numerical modeling published in the Stapp Car Crash Conference Proceedings and Journal were reviewed. These models were based on: (a) author-developed equations and software, (b) public and commercially available programs to solve rigid body dynamic models (such as MVMA2D, CAL3D or ATB, and MADYMO), and (c) finite element models.

A detailed investigation of influence of friction on drawbead restraining force modeling is presented in this paper. It is motivated by the need to accurately correlate line bead strengths, which are usually the output of an optimized draw development for controlling materials flow and achieving desired formability, and the physical drawbead geometries required for die face engineering. A plane-strain drawbead model with linear Coulomb friction is first established and the restraining forces corresponding to a range of bead penetration depths are obtained. The comparison of the simulation results with experimental data indicates that, while a larger Coefficient of Friction (COF) has better correlation for smaller bead penetrations and smaller COF does better for deeper bead penetrations, no single COF matches satisfactorily for overall range of bead penetration depths.