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This paper presents an evaluation of a vehicle dynamics model intended to be used for the National Advanced Driving Simulator (NADS). Dynamic validation for high performance simulation is not merely a comparison between experimental and simulation plots. It involves strong insight of vehicle's subsystems mechanics, limitations of the mathematical formulations, and experimental predictions. Lateral, longitudinal, and ride dynamics are evaluated using field test data, and analytical diagnostics. The evaluation includes linear and non-linear range of vehicle dynamics response.

The evolution of the diagnostic equipment for automotive application is the direct effect of the implementation of sophisticated and high technology control systems in the new generation of passenger cars. One of the most challenging issues in automotive diagnostics is the ability to assess, to analyze, and to integrate all the information and data supplied by the vehicle's on-board computer. The data available might be in the form of fault codes or sensors and actuators voltages. Moreover, as environmental regulations get more stringent, knowledge of the concentration of different species emitted from the tailpipe during the inspection and maintenance programs can become of great importance for an integrated powertrain diagnostic system. A knowledge-based diagnostic tool is one of the approaches that can be adopted to carry out the challenging task of detecting and diagnosing faults related to the emissions control system in an automobile.

Friction plays an important role in the deep drawing process. Previous research shows friction condition can be tailored by applying micro-textures on tooling surfaces. A friction model is proposed to reveal the mechanism of altering friction condition by configuring micro-texture. A discrete friction concept is proposed to improve drawability of sheet metal and demonstrates numerically on a non-symmetric geometry drawing process.

A number of automotive diagnostic equipment and procedures have evolved over the last two decades, leading to two generations of on-board diagnostic requirements (OBDI and OBDII), increasing the number of components and systems to be monitored by the diagnostic tools. The goal of On-Board Diagnostic is to alert the driver to the presence of a malfunction of the emission control system, and to identify the location of the problem in order to assist mechanics in properly performing repairs. The aim of this paper is to suggest a methodology for the development of an Integrated Powertrain Diagnostic System (EPDS) that can combine the information supplied by conventional tailpipe inspection programs with onboard diagnostics to provide fast and reliable diagnosis of malfunctions.

Design charts which predict acoustic absorption of porous insulators were verified experimentally using the two-microphone technique to measure the normal incidence absorption coefficient of three glass fiber materials in two different arrangements - a single-layer sample and a single layer in front of an air space, each backed by a rigid termination. The specific flow resistivities of the materials ranged from 2,000 to 52,000 mks rayls/m. Experimentally determined absorption coefficients were in agreement with those predicted by the design charts. The results indicate that these charts could be a useful tool in designing sound absorbers for practical applications.

The introduction of advanced electronic controls in passenger vehicles over the last decade has made traditional diagnostic methods inadequate to satisfy on- and off-board diagnostic needs. Due to the complexity of today's automotive control systems, it is imperative that appropriate diagnostic tools be developed that are capable of satisfying current and projected service and on-board requirements. The performance of available diagnostic and test equipment is still amenable to further improvement, especially as it pertains to the diagnosis of incipient and intermittent faults. It is our contention that significant improvement is possible in these areas. This paper briefly summarizes the evolution of on- and off-board diagnostic tools documented in the published literature, with the aim of giving the reader an understanding of their capabilities and limitations, and it further proposes alternative solutions that may be adopted as a basis for an advanced diagnostic instrument.