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This paper presents an overview of the evolution & revolution of automotive E/E architectures and how we at Bosch, envision the technology in the future. It provides information on the bottlenecks for current E/E architectures and drivers for their evolution. Functionalities such as automated driving, connectivity and cyber-security have gained increasing importance over the past few years. The importance of these functionalities will continue to grow as these cutting-edge technologies mature and market acceptance increases. Implementation of these functionalities in mainstream vehicles will demand a paradigm shift in E/E architectures with respect to in-vehicle communication networks, power networks, connectivity, safety and security. This paper expounds on these points at a system level.

In the context of the energy transition, CO2-neutral solutions are of enormous importance for all sectors, but especially for the mobility sector. Hydrogen as an energy carrier has therefore been the focus of research and development for some time. However, the development of hydrogen combustion engines is in many respects still in the conception phase. Automotive system providers and engineering companies in the field of software development and simulation are showing great interest in the topic. In a joint project with the industrial partners Robert Bosch GmbH and AVL Germany, combustion in a H2-DI-engine for use in light-duty vehicles was methodically investigated using the CFD tool AVL FIRE®. The collaboration between Robert Bosch GmbH and the Institute for Mobile Systems (IMS) at Otto von Guericke University Magdeburg has produced a model study in which model approaches for the combustion of hydrogen can be analyzed.

The development of future automotive electronic systems requires new concepts in the software architecture, development methodology and information exchange. At Bosch an XML and MSR based technology is applied to achieve a consistent information handling throughout the entire software development process. This approach enables the tool independent exchange of information and documentation between the involved development partners. This paper presents the software architecture, the specification of software components in XML, the process steps, an example and an exchange scenario with an external development partner.

The contribution presents a new data driven modeling approach for diesel HCCI combustion. Input parameters of the combustion model are external actuating variables as for example the start of injection. The model incorporates experimental data of the engine in HCCI mode, in the standard diesel mode and in the transition region between both modes. New disclosed dependencies between characteristic values of the cylinder pressure and the fuel burn rate are used to linearize the combustion model for a given operating point. In this paper the validation of the combustion model is discussed based on dynamic measuring data of the urban part of the NEDC. Finally, the combustion model is integrated in a zero-dimensional diesel engine model.

The emission of particulate matter from future GDI engines has to be optimized, to comply with more stringent emission standards such as EU6. Therefore, the mechanisms responsible for the formation of particles have to be analyzed in detail. The understanding of the in-cylinder processes, necessary for this purpose, can only be achieved by a complementary use of optically accessible single-cylinder engines as well as the numerical simulation. This however leads to great demands on the 3D flow simulation. In this paper the complete CFD approach, incorporating a detailed description of the entire underlying model chain is shown. Particularly the wall surface temperature and the temperature drop due to the interaction with liquid fuel spray were identified as important parameters influencing the spray-wall interaction and thus also the particulate emissions. Nevertheless, in conventional CFD models, the spray cooling cannot be captured because of an assumed constant wall temperature.

Particulate emissions from Gasoline Direct Injection (GDI) engines have been an important topic of recent research interest due to their known environmental effects. This review paper will characterise the influence of different gasoline direct injection fuel systems on particle number (PN) emissions. The findings will be reviewed for engine and vehicle measurements with appropriate driving cycles (especially real driving cycles) to evaluate effects of the fuel injection systems on PN emissions. Recent technological developments alongside the trends of the influence of system pressure and nozzle design on injector tip wetting and deposits will be considered. Besides the engine and fuel system it is known that fuel composition will have an important effect on GDI engine PN emissions. The evaporation qualities of fuels have a substantial influence on mixture preparation, as does the composition of the fuel itself.

Mathematical modelling has proved to be a valuable tool for understanding the performance of diesel injection systems. There are several programs for the simulation of conventional injection equipment, but up to now it has been very expensive to simulate new concepts of injection equipment. Therefore a general program system for simulation of transient hydraulic processes - especially in diesel injection systems - has been developped. By this system, any new injection equipment can be simulated user-friendly and without needing to write new programs. The differential equations are solved by mathematical methods, which promise stability in all conditions and offer short calculation times. Since 1983 the program system has been applied to a lot of non-conventional and conventional injection systems and has proved its reliability.

Antilock Braking Systems (ABS) and Traction Control Systems (ASR) should ensure maximum stability and steerability even under extreme driving conditions. Since high performance systems additionally improve brake distance and traction within the given physical limits, every vehicle equipped with ABS and ASR offers considerably higher active safety. ABS was introduced into the market by the Robert Bosch GmbH more than ten years ago, and more than 3 million systems have been produced by the end of 1988. Volume production of ASR began in 1987. This paper describes several high-, medium-, and low performance concepts and compares them with regard to safety and performance. Although it seems to be nearly impossible to define a cost/benefit ratio between monetary values and safety, our purpose here is to identify further development strategies through the use of a decision matrix.

In 1978, Bosch was the first supplier on the market to offer full-function antilock braking systems. In 1993, six years will have passed since Bosch delivered the first traction control system for passenger cars. In the meantime, a considerable amount of experience has been gained through ongoing development and testing. This experience enabled us to define the requirements for directional stability, optimum control strategy, maximum usage of the entire spectrum of drive torque intervention possibilities, and optimized hydraulics for automatic brake intervention. The result is Bosch ABS/ASR5, which in now being introduced to the market. This new ABS/ASR family is designed in modules, which offers high flexibility in function and assembly. Systems are available with traction improvement, or with optimized directional stability and traction. Each version is adapted to the needs of the vehicle drive layout, and adaptable to customer requirements.

The transition from the multi-component ABS2 design to the one housing concept of ABS5.0 represented a significant step in improving the ABS unit. ABS5.3 is the successor of ABS5.0 to achieve a highly compact, light weight inexpensive design, for the broad use of ABS in all passenger cars and light trucks. New technologies applied are the staking technique for hydraulic components, the use of microhybrid electronics design and solenoid coils being integrated within the attached electronic control unit. The unit can be manufactured in global alliance achieved by simultaneous engineering, applying CAD, FE-analysis, flow calculation and simulation, noise analysis and quality assurance which includes FMEA, error simulation, durability tests and the dry testing concept. The ABS5.3 design can be easily expanded to Traction Control (ASR).

Control of a car is lost, or considerably reduced, whenever one or more of the wheels exceed the stability limit during braking or accelerating due to excessive brake or drive slip. The problem of ensuring optimum stability, steerability and brake distance of a car during hard braking is solved by means of the well-known Anti-lock Braking System (ABS). The task to guarantee stability, steerability and optimum traction during acceleration, particularly on asymmetrical road surfaces and during cornering maneuvers, is being performed by the traction control system (ASR). Several means to provide an optimum traction control are described, e. g the control of engine torque by influencing the throttle plate and/or the ignition and/or the fuel injection.

Closed loop vehicle control comprising of the driver, the vehicle and the environment is now achieved by the automatic wheel slip control combination of ABS and ASR. To improve directional control during acceleration, the Robert Bosch Corporation has introduced five ASR-Systems into series production. In one system, the electronic control unit works exclusively with the engine management system to assure directional control. In two other systems, brake intervention works in concert with throttle intervention. For this task, it was necessary to develop different highly sophisticated hydraulic units. The other systems improve traction by controlling limited slip differentials. The safety concept for all five systems includes two redundant micro controllers which crosscheck and compare input and output signals. A Traction Control System can be achieved through a number of torque intervention methods.

Pedestrian protection is an upcoming field for research and development. Active pedestrian protection is described from a system perspective. In this view, the development of an active pedestrian protection system is shown. First an overview on statistics and legal requirements is given and the system requirements are discussed. Sensor concepts and realizations are shown, also different test methods and results are explained. FE-simulations to complete and later replace additional tests are developed, after cross check with the experimental results. In combination with the shown actuator concept this leads to a full functioning active pedestrian protection system.

This paper reports on the application of model-based diagnosis techniques to diesel engine management systems within the Brite-EuRam project “Vehicle Model Based Diagnosis”. We discuss some major requirements that have been identified in this application. In particular, it is essential to solve the inherent variant problem, to reason across different physical domains and to fulfill real-time needs for on-board diagnosis. The main foundation of our approach is to use qualitative models, especially qualitative deviation models, which serve as a coherent modeling paradigm for the different domains. In the project, this technology has been implemented and evaluated for on-board diagnosis on two demonstrator vehicles. The paper also discusses further perspectives of the technology for tools supporting the development and implementation of on-board diagnosis.

In conventional sensor systems, mechanical and electronic components are generally operating at separated locations. Smart sensors integrate mechanical and electronic elements to a single system, thus offering new facilities for a common error compensation. In this concept, a unit-specific temperature dependence and a non-linear characteristic curve of the mechanical sensor element can be tolerated, thus saving a lot of costs in the manufacturing process of the mechanical components. The behaviour of the mechanical sensor element is described by a two-dimensional sensor correction function: Given the output of the mechanical sensor element and a measured value for the temperature, the true measurement value can be calculated by an error correction unit. In this paper, different error correction methods are examined and evaluated which can be used for a wide range of sensor types. They are applied to the example of a short-circuit ring displacement sensor.

The present paper concentrates on the option of catalytic autothermal reforming of gasoline for fuel cell applications. Major parameters of this process are the “Steam to Carbon Ratio” S/C and the air to fuel ratio λ. Computations assuming thermodynamic equilibrium in the autothermal reactor outlet (ATR) were carried out to attain information about their proper choice, as failure in adjusting the parameters within narrow limits has severe consequences on the reforming process. In order to quantify velocity distribution just ahead the catalyst and to evaluate mixing uniformity we designed an ATR featuring an optical access: Thus flow visualization using PIV (Particle Image Velocimetry) and LIF (Laser Induced Fluorescence) technique is possible. Preliminary PIV-results are presented and compared with CFD computations (Computational Fluid D ynamics).

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.

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 selective catalytic reduction (SCR) based on urea-water-solution is an effective technique to reduce nitrogen oxides (NOx) emitted from diesel engines. A 3D numerical computer model of the injection of urea-water-solution and their interaction with the exhaust gas flow and exhaust tubing is developed to evaluate different configurations during the development process of such a DeNOx-system. The model accounts for all relevant processes appearing from the injection point to the entrance of the SCR-catalyst: momentum interaction between gas phase and droplets evaporation and thermolysis of droplets hydrolysis of isocyanic acid in gas phase heat transfer between wall and droplets spray/wall-interaction two-component wall film including interaction with gas phase and exhaust tube The single modeling steps are verified with visualizations, patternator measurements, phase-doppler-anemometer results and temperature measurements.

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.