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Automotive product lines promote reuse of software artifacts such as architectures, designs and implementations. System architectures, and especially software architectures, are difficult to create due to the need to support variations. Traditional approaches emphasize the identification and description of generic components, which makes it difficult to support variations among products. The paper proposes an approach for transforming a software architecture to product design through using patterns in a four-way refinement and evolution process. The paper investigates how patterns may be used to verify the conceptual integrity in the view integration procedure to support software sharing in an open automotive system.

This study reports on laser-based diagnostics to temporally track the evolution of liquid and gaseous fuel in the cylinder of a direct injection production type Diesel engine. A two-dimensional Mie scattering technique is used to record the liquid phase and planar laser-induced fluorescence of Diesel is used to track both liquid and vaporised fuel. LIF-Signal is visible in liquid and gas phase, Mie scattering occurs only in zones where fuel droplets are present. Distinction between liquid and gaseous phase becomes therefore possible by comparing LIF- and Mie-Signals. Although the information is qualitative in nature, trends of spray evolution are accessible. Within this study a parametric variation of injection pressure, in-cylinder conditions such as gas temperature and pressure as well as piston geometry are discussed. Observations are used to identify the most sensitive parameters and to qualitatively describe the temporal evolution of the spray for real engine conditions.

Vehicle inspection in repair shops is often still based on paper forms. Information Technology (IT) does not yet support the entire inspection process. In this paper, we introduce a small wearable IT device that is controlled by speech and enables service technicians to wirelessly access relevant data and to perform on-site communication. Users can carry this device in a pocket and use a small headset to enter speech and receive audio feedback. This system provides a completely speech-enabled functionality and thus offers a hands-free operation. After showing the applicability of wearable computers in this environment, we developed a proprietary hardware system consisting of a thin-client connected via a Digital Enhanced Cordless Telecommunications (DECT) link to a standard Personal Computer (PC) that runs a speech engine and hosts a database. Several field tests in garages helped us during the evolution of our prototypes where service technicians critiqued the prototypes.

Pre-crash functionality is defined in three functional steps: PRESET, PREFIRE and PREACT. The functional steps are described in the order of growing situation analysis performance requirements and an increasing amount of necessary system application effort. Each functional step defines its own range of view, the so-called virtual barrier. The definition of the virtual barrier is subject to various constraints in respect to sensor configuration and pre-crash performance. A more detailed description of PRESET functionality for frontal pre-crash is given together with a test example. Pre-crash sensing technology uses platform radar sensors. The platform sensors are designed for the integration of all possible functions that rely on sensor information from the close surroundings of the vehicle. This development approach guarantees a high cost efficiency, flexibility and modularity of the sensor system while still guaranteeing the full pre-crash functionality.

Among the currently available sensor interfaces for automotive applications, only the PSI5 interface - as standardized in the new 2001 PSI5 V2.0 - meets the rising system requirements, the increased requirements of the new environmental regulations, and the requirements of current functional safety standards. PSI5 not only features the capability to transmit highly accurate sensor data, high EMC robustness, bus capability, and bidirectional communication, but also offers savings in the cable harness and a reduced number of connector pins by using just two wires. It therefore offers enhanced technical functionality at a reasonable cost. To improve the environmental friendliness and sustainable operation of drive concepts, Bosch is also employing sophisticated and cross-linked sensors, actuators and control units. In addition, there is also the need to optimize system functions, weight, construction space and costs.

The electrification of vehicles marks the introduction of new products to the automotive market and a continued effort to optimize their performance. The electric motor is an important component with which a further optimization of efficiency, power density and cost can be achieved. Additional benefits can be realized in the laminated core. This paper presents an innovative method to produce laminated stacks by a chain of processes different from conventional ways. The process chain presents a sequence of precision blanking, buffering, heat treatment and gluing. The effect of these processes is compared with existing solutions that typically contain some individual features but usually not the combination that enhances the overall effect. The heat treatment decreases residual stresses from previous process steps and reduces power losses in the laminated core. Depending on the design, benefits around 20% are found.

Ultrasonic transducers are widely used in automotive and industrial applications for surround sensing. Anisotropic directivity patterns with a narrow-angled beam in the vertical plane and a wide-angled beam in the horizontal plane are needed in automotive applications particularly. Today’s ultrasonic transducers for automotive applications are mainly metal based, pot-like ultrasonic transducers. The anisotropic directivity pattern is achieved by increasing the thickness of the vibrating plate-like part of the structure locally. Composites with locally structured fiber reinforcements open up the possibility to design the dynamical behavior of components without changing its contour. Using this new dimension of design to modify the directivity pattern of sound radiating components is less examined in literature.

A major source for soot particle formation in Gasoline-Direct-Injection (GDI) engines are fuel-rich zones near walls as a result of wall wetting during injection. To address this problem, a thorough understanding of the wall film formation and evaporation processes is necessary. The wall temperature before, during and after fuel impingement is an important parameter in this respect, but is not easily measured using conventional methods. In this work, a recently developed laser-based phosphor thermography technique is implemented for investigations of spray-induced surface cooling. This spatially and temporally resolved method can provide surface temperature measurements on the wetted side of the surface without being affected by the fuel-film. Zinc oxide (ZnO) particles, dispersed in a chemical binder, were deposited onto a thin steel plate obtaining a coating thickness of 17 μm after annealing.

Large Eddy Simulations (LES) and tracer-based Laser-Induced Fluorescence (LIF) measurements were performed to study the dynamics of fuel wall-films on the piston top of an optically accessible, four-valve pent-roof GDI research engine for a total of eight operating conditions. Starting from a reference point, the systematic variations include changes in engine speed (600; 1,200 and 2,000 RPM) and load (1000 and 500 mbar intake pressure); concerning the fuel path the Start Of Injection (SOI=360°, 390° and 420° CA after gas exchange TDC) as well as the injection pressure (10, 20 and 35 MPa) were varied. For each condition, 40 experimental images were acquired phase-locked at 10° CA intervals after SOI, showing the wall-film dynamics in terms of spatial extent, thickness and temperature.

Rapid opening, closing and rebounds of needle from seat and stopper plate give rise to fluid transients in fuel injectors, which are strongly coupled to the dynamics of needle and body motions. A mathematical model, based on unsteady compressible flow in the injector and steady incompressible flow in inlet and outlet section in conjunction with the equation of motion for needle and body, allows the quantitative description of the injector operation cycle. Agreement between prediction and experiment in terms of needle motion, needle velocity and pressure history is good. The mathematical model is used to show the effects, which various contributions to the hydrodynamic interaction force have on the needle motion, on pressure history and on injected mass.

On the way to automated driving, the installation rate of surround sensing systems will rapidly increase in the upcoming years. The respective technical progress in the areas of driver assistance and active safety leads to a numerous and valuable information and signals to be used prior to, during and even after an accident. Car makers and suppliers can make use of this new situation and develop integrated safety functions to further reduce the number of injured and even deaths in car accidents. Nevertheless, the base occupant safety remains the core of this integrated safety system in order to ensure at least a state-of-the-art protection even in vehicles including partial, high or full automation. Current networked safety systems comprehend a point-to-point connection between single components of active and safety systems. The optimal integration requires a much deeper and holistic approach.

In order to optimize the performance and emission of engines, advanced control and diagnostic systems require detailed feedback information about the combustion process. In this context, cost-effective solutions are of interest. The contribution describes a method for reconstructing cylinder-individual features of each combustion cycle by processing the instantaneous fluctuations of the engine speed and the in-cylinder pressure of one cylinder. Model-based torque estimation, analyzing both of the signals simultaneously, provides an accurate estimation of the mean indicated pressure. Using this method, a new algorithm for advanced misfire detection is presented. Furthermore, a new pressure model with a feasible number of parameters is proposed. It is combined with the torque estimation in order to reconstruct the unknown pressure traces of the cylinders not equipped with sensors.

Aerodynamic styling is playing an increasing role in the design of today's passenger cars. The profile sections of the frontends of cars imply that the available installation space for the headlamps - particularly its overall depth and height is decreased in size. New types of headlamps had to be developed. One result of extensive investigations are stepped reflectors with up to six paraboloids with different focal lengths arranged around the same focal point. This type of reflector (called homofocular reflector) cannot be formed from sheet steel but from plastic by injection molding. Depending on thermal, mechanical and geometric boundary conditions three different reflector materials can be used: lacquered thermosets, unlacquered thermoplastics by one or two material injection moldings. Similar to sheet steel the use of glass lenses reduces considerably the freedom of the designer. This disadvantage of offset by the use of plastic lenses.

Future emission standards for heavy-duty vehicles like Euro 4, Euro 5, US '07 require advanced engine functionality. One contribution to achieve this target is the catalytic reduction of nitrogen oxides by injection of urea water solution to the exhaust gas. An overview on a urea dosing system, also called DENOXTRONIC, is given and a dosing strategy is described.

Until now, the use of biometric systems has not been in the public eye. The high cost of sensors and processing has meant that biometrics was previously restricted to high security access, financial transaction and law enforcement applications. However, as a result of improvements in technology, biometric sensor price and reliability have achieved levels where biometrics is being seriously considered for automotive systems. This paper introduces the field of biometrics, the key terms and processes. Fingerprint Technology and Identification by Fingerprint are discussed, as are the use and applicability of biometrics in automotive applications, including Personal Profiling, Keyless Engine Start and vehicle access authorization. The key findings of investigations over the last years are discussed.

Due to its high number of free parameters, the new generation of gasoline engines with direct injection require an efficient calibration process to handle the system complexity and to avoid a dramatic increase in calibration costs. This paper presents a concept of specific toolboxes within a standardized and automated calibration environment, supporting the complexity of GDI engines and establishing standard procedures for distributed development. The basic idea is the combination of a new and more efficient online DoE approach with the automatic and adaptive identification of the region of interest in the high dimensional parameter space. This guarantees efficient experimental designs even for highly non-linear systems with often irregularly shaped valid regions. As the main advantage for the calibration engineer, the new approach requires almost no pre-investigations and no specific statistical knowledge.

The paper begins with an overview of the history of ABS for commercial vehicles followed by a brief description of the technology of the BOSCH ABS at the time it went into mass production in 1981. Subsequently it describes the field experiences with ABS including the experiences of drivers and operators. These experiences are reflected in the equipment which BOSCH offers today. Additional functions such as ASR (traction control) have been integrated. The paper provides an overview of the functions available today and their implementation. The paper concludes with a discussion on potential continued developments and an attempt to describe the systems which will be required by the mid 9os.

Safety-critical embedded software has to satisfy stringent quality requirements. One such requirement, imposed by all contemporary safety standards, is that no critical run-time errors must occur. Runtime errors can be caused by undefined or unspecified behavior of the programming language; examples are buffer overflows or data races. They may cause erroneous or erratic behavior, induce system failures, and constitute security vulnerabilities. A sound static analyzer reports all such defects in the code, or proves their absence. Sound static program analysis is a verification technique recommended by ISO/FDIS 26262 for software unit verification and for the verification of software integration. In this article we propose an analysis methodology that has been implemented with the static analyzer Astrée. It supports quick turn-around times and gives highly precise whole-program results.

This study presents measurements of transient flow field and spray structures inside an optically accessible DISI (direct-injection spark-ignition) internal combustion engine. The flow field has a direct effect upon mixture and combustion processes. Given the need to increase the efficiency and performance of modern IC engines and thus reduce emissions a detailed understanding of the flow field is necessary. The method of choice was high-speed two-component particle image velocimetry (PIV) imaging a large field of view (43 x 44 mm₂). To capture the temporal evolution of the main flow features the repetition rate was set to 6 kHz which resolves one image per 1° crank angle (CA) at 1000 rpm. The crank angle range recorded was the latter half of the compression stroke at various engine speeds as well as various charge motions (neutral, tumble and swirl). Moreover, consecutive cycles were recorded allowing a detailed investigation of cycle-to-cycle variations.

The official Indian accident statistics show that the number of road accidents and fatalities are one of the highest worldwide. These official statistics provide important facts about the current accident situation. It is suspected that for various reasons not all accidents are reported to the official statistic. This study estimates the degree of underreporting of traffic accidents with casualties in India. In order to get a national overview of the traffic accident situation it is necessary to improve the knowledge about underreported accidents. Therefore, the in-depth accident database of “Road Accident Sampling System India” (RASSI) was analyzed [1]. This project is organized by a consortium that has collected traffic accidents scientifically in four different regions since 2011 on the spot which have been reported either by police or by local hospitals and own patrol by RASSI engineers.