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This paper discusses a methodology for calculating the probability of a redundant system to fail in a specified time interval after a first fault has occurred. That probability is first derived in general and then specified for a system consisting of independent components having exponential failure rate densities. Four different redundant system configurations of a safety relevant automotive control system are discussed and compared with respect to their reliability characteristics. The four configurations differ in system topologies as well as the intelligence of the system components with respect to self-monitoring.

Integrated Chassis Management ICM is a novel and demanding approach to develop a vehicle chassis and all its control systems in a common process which explicitly addresses the interrelations between them. Primary aims are the improvement of driving safety and comfort by creating synergies in the use of sensor information, hardware, and control strategies. The Electronic Brake Management EBM is an essential part of ICM and an important step to its development.

Fast and exact measurement of engine oil consumption is a very difficult task. Our aim is to achieve this measurement at a common test bed without engine modifications. We resolved this problem with a new technique using Laser Mass Spectrometry to detect appropriate tracers in the raw engine exhaust. The tracers are added to the engine oil. to the engine oil. For detection of these tracers we use a Laser Mass Spectrometer (LAMS). This is a combination of resonant laser ionization (with an all-solid-state laser) and Time-of-Flight Mass Spectrometry. Currently this is the only way to detect oil originated molecules (like our tracers) in the raw exhaust very fast (50 Hz) and sensitive (ppb-region). Thus, engine mapping of oil consumption over load and speed can be performed in 1-2 days with about 90 measurements. Even measurement during dynamic engine operation is possible, but not quantitative (due to the lack of information about dynamic exhaust gas mass flow).

The Columbus Orbital Facility (COF) is being developed as the European Laboratory contribution to the International Space Station (ISS) program. The COF Active Thermal Control System (ATCS) is based on a single phase water loop for the collection of waste heat from payloads and subsystems and the rejection to the ISS Heat Exchangers (HXs). During 1993 the budget constraints and the shifting to November 2002 of the European Laboratory launch led to an incremental qualification approach for the COF ATCS water loop: to qualify the ATCS water loop by analysis using mathematical models correlated throughout a series of testing. The water loop testing has been developed through different incremental steps whose results were correlated by means of ESATAN-FHTS models. The water loop setup testing was upgraded, step by step, by using commercial and flight representative items on the basis of the equipment development status.

Exhaust acoustics simulation is an important part of the exhaust system process. Especially important is the trend towards a coupled approach to performance and acoustics design. The present paper describes a new simulation tool developed for such coupled simulations. This tool is based on a one-dimensional fluid dynamics solution of the flow in the engine manifolds and exhaust and intake elements. To represent the often complex geometries of mufflers, an easy-to-use graphical pre-processor is provided, with which the user builds a model representation of mufflers using a library of basic elements. A comparison made to two engines equipped with exhaust silencers, shows that the predictions give good results.

In order to optimise the vibro-acoustic behaviour of panel-like structures in a more systematic way, accurate structural models are needed. However, at the frequencies of relevance to the vibro-acoustic problem, the mode shapes are very complex, requiring a high spatial resolution in the measurement procedure. The large number of required transducers and their mass loading effects limit the applicability of accelerometer testing. In recent years, optical measuring methods have been proposed. Direct electronic (ESPI) imaging, using strobed continuous laser illumination, or more recently, pulsed laser illumination, have lately created the possibility to bring the holographic testing approach to the level of industrial applicability for modal analysis procedures. The present paper discusses the various critical elements of a holographic ESPI modal testing system.

This paper describes a strategy that allows a vehicle builder to quickly design and build an electrical communication and control system infrastructure. The power, ground, and communication infrastructure connects readily available operator interfaces and other electromechanical devices together with high level controllers to provide a complete vehicle electrical system.

Innovative electric systems demand a new approach for the distribution of electric energy in passenger cars. This paper describes a very promising solution-the dual voltage power network with an upper voltage level of 42V, and the considerations which led to the selection of this voltage level. Owing to the significant impact on the industry, a common standard is required. Depending on their profile, OEMs will select their own strategies for implementation, either as a base for innovation or to enhance overall system efficiency. This will lead to different approaches and timeframes.

As features in vehicles and their associated loading on the vehicle's power supply increase, the existing 14V power supply system is being pushed to its limits. At some point it will be necessary to provide a complementary higher supply voltage for higher power loads to ensure reliable operation. Industry efforts have been underway to define the next step(s) toward a common architecture. These efforts are currently focused on a dual voltage 14V/42V system with specified voltage limits. A change in the vehicle's power supply voltage and over-voltage specifications have a direct impact on semiconductors. Cost, reliability, available process technology, and packaging are among the areas that are affected. Reducing or eliminating the load dump transient can provide cost reduction, especially for power switching devices. Smart semiconductor switches with integrated diagnostic and protection features provide the potential to replace fuses in the new architecture.

As the new generation of RISC powertrain MCUs propagate through the automotive development cycle, there will likely be more difficulty in debugging the ECU reliably and efficiently. Simply stated, there is less support for the development process in the new high-performance single-chip RISC MCUs, which could create critical and costly delays in the development cycle. Additionally, as powertrain MCUs continue to evolve, superscalar or multiple-issue RISC implementations may be used as the central processor. With the capability to issue multiple instructions in one clock cycle, this will only magnify the development support problem. Thus it is essential to address this impending problem with a strategy that both automotive and tools developers can agree. A strategy for development standards is presented in this paper, and a new powertrain MCU development interface standard is proposed.

The study of oil emission is of essential interest for the engine development of modern cars, as well as for the understanding of hydrocarbon emissions especially during cold start conditions. A laser mass spectrometer has been used to measure single aromatic hydrocarbons in unconditioned exhaust gas of a H2-fueled engine at stationary and transient motor operation. These compounds represent unburned oil constituents. The measurements were accompanied by FID and GC-FID measurements of hydrocarbons which represent the burned oil constituents. The total oil consumption has been determined by measuring the oil sampled by freezing and weighing. It has been concluded that only 10 % of the oil consumption via exhaust gas has burned in the cylinders. A correlation of the emission of single oil-based components at ppb level detected with the laser mass spectrometer to the total motor oil emission has been found.

Wheel slip control system have found a remarkable penetration in all car segments. The information on the wheel behavior has lead to further developments which control the brake performance as well as the driving of the car in general. Latest systems introduced especially on luxury cars use wheel individual brake intervention to ensure vehicle stability under various driving maneuvers within the physical limits. Such systems use vehicle dynamic sensors and special hydraulics which serve as energy source for the automatic brake application. The technical effort of such systems like the Dynamic Stability Control DSC has limited the installation to upper class cars so far. New approaches are required to allow for a more wide spread penetration. Optimized hydraulics together with a rational design of the electronics seems to offer a basis for a more cost effective design.

This paper is going to discuss typical requirements for micromachined sensors. The most common examples today are pressure and acceleration sensors. We will discuss the function and applications of pressure and acceleration sensors. There are two differences between accelerometers and pressure sensors: sensor technology and signal conditioning. Pressure sensors employ bulk micromachining techniques where accelerometers use surface micromachining. Pressure sensors are typically signal conditioned with bipolar circuitry. Acceleration sensors use CMOS signal conditioning. We will also explain the electrical characteristics of both pressure and acceleration sensors along with mechanical package styles. We will be focusing our effort on automotive based applications. Some typical applications for pressure sensors in the automotive environment are MAP, BAP, lumbar seat, air bag and tire pressure. The requirements of the MAP/BAP application will also be discussed in detail.

This paper presents an object-oriented method customized for a tool-assisted development of car software components. Tough market conditions motivate smart software development. ASCET SD is a tool to generate target code from graphic specifications, avoiding costly programming in C. But ASCET lacks guidelines on what to do, how to do it, in what order, like a fully equipped kitchen without a cooking book. Plans to employ the tool for BMW vehicle software sparked off demand for an adequate, object-oriented real-time methodology. We show how to scan the methodology market in order to adopt an already existing method for this purpose. The result of the adaptation of a chosen method to ASCET SD is a pragmatic version of ROOM, which we call BROOM. We present a modeling guidebook that includes process recommendations not only for the automotive sector, but for real-time software development in general.

Increasing demand for dynamically controlled safety features, passenger comfort, and operational convenience in upper class automobiles requires an intensive use of electronic control units including software portions. Modeling, simulation, rapid prototyping, and verification of the software need new technologies to guarantee passenger security and to accelerate the time-to-market of new products. This paper presents the state-of-the-art of the design methods for the development of electronic control unit software at BMW. These design methods cover both discrete and continuous system parts, smoothly integrating the respective methods not merely on the code level, but on the documentation, simulation, and design level. In addition, we demonstrate two modeling and prototyping tools for discrete and continuous systems, namely Statemate and MatrixX, and discuss their advantages and drawbacks with respect to necessary prototyping demands.

The automotive pressure sensor is one of the most widespread applications of a micromachined device, and has evolved into a relatively mature technology, expanding beyond its original use as an engine control sensor into other vehicle control and diagnostic systems. The need for flexibility in various applications, low cost, high volume manufacturing capability, and survivability in harsh environments has strongly influenced sensor signal conditioning, calibration, element design, and packaging. Many of the issues affecting the development and commercialization of micromachined automotive pressure sensors are also relevant to other emerging microfabricated devices. This paper shows how the commercial success of a product using microfabricated technology is highly dependent upon other core competencies, beyond just the capability to perform the micromachining operations necessary to create the sensing device.

A monolithic sensing solution for manifold absolute pressure (MAP) is presented. This work includes examination of design, fabrication, temperature compensation, packaging and electromagnetic compatibility (EMC) testing of the fully integrated monolithic sensor. The circuit uses integrated bipolar electronics and conventional IC processing. The amplification circuit consists of three op-amps, seven laser trimmable resistors, and other active and passive components. Also discussed is a summary of an automotive application MAP sensor general specification, test methods, assembly, packaging, reliability and media testing for a single chip solution.

An Integrated Barometric Absolute Pressure Sensor (IBAP) solution for barometric pressure sensing is presented here. The IBAP is a silicon bulk micromachined monolithic pressure sensor. This work includes an examination of the design, fabrication, temperature compensation, and testing aspects. In addition, options and issues related to the mounting of the IBAP device will be presented. Two techniques, including surface mounting the sensor on the engine control unit (ECU) PWB are discussed.

The production of the BMW ALPINA B12 5.7 with Switch-Tronic transmission provides the markets of Europe and Japan with an exclusive, luxury-orientated, high performance limited series limousine. This is the first vehicle worldwide to be fitted with the progressive exhaust gas aftertreatment technology known as the Electrically Heated Catalyst (EHC), in which the effectiveness of the power utilized is increased significantly by an alternating heating process for both catalytic converters. Only since this achievement has the implementation of the EHC been viable without extensive modification to the battery and alternator. With this exhaust gas aftertreatment concept, the emissions of this high performance vehicle will fall to less than half the maximum permissible for compliance with 1996 emission standards.

A lot of very valuable information has already been gained in the process of dismantling, assorting and reconditioning plastic parts on old cars, in reconditioning defective plastic parts from workshops, and in the use of reject parts from production. This know-how is now applied primarily to increase the use of recycled plastics and to optimise the composition and design of future plastic components in the interest of recycling, since further development in these areas is essential in order to establish economically stable material cycles functioning properly in the long term. The present paper describes the most important criteria through which the materials and designs chosen affect the processes and principles of recycling in the case of plastic parts and components.