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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.

For the development of future safety-relevant automotive electronic systems a thorough adaptation of the existing design process is necessary to consider safety and reliability in a more systematic way. In this paper an approach for a new design methodology is presented. It is based on the V-Model which is the established process model for the development of electronic and software systems in the automotive domain. For an advanced consideration of safety and reliability the existing process is extended by a second V (with process elements that have a special focus on safety and reliability) to a “Double V”. The new elements are interconnected with the existing ones at several points of time during the development process. By a defined information exchange between the two Vs continuity in the methodology is guaranteed. Basis for the extension are experiences of the aerospace domain that were adopted to automotive conditions.

The correct timing of the diesel injection pump on engine is of major importance for all functions of the engine and for its exhaust emissions, during production pass off as well as in the field. Within the diesel service workshops a variety of devices exist to test the timing of the injection pump on engine. Most of them operate by clamp-on transducer being fitted to the injection pipe. A large uncertainty exists concerning the accuracy of such timing systems. Most diesel engine manufacturers do not have confidence in the timing devices capability and, therefore, do not recommend their usage. A working group within the International Organization for Standardization (ISO) adopted a method for the validation of these measurement systems, which usually is used to judge the capability of measurement gauges for industrial production processes.

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.

Stricter emissions legislation and growing demands for lower fuel consumption require significant efforts to improve combustion efficiency while satisfying the emission quality demands. Controlled Homogeneous Charge Compression Ignition (HCCI) combined with boosted air systems on gasoline engines provides a particularly promising, yet challenging, approach. Naturally aspirated (NA) HCCI has already shown considerable potential in combustion efficiency gains. Nevertheless, since the volumetric efficiency is limited in the NA HCCI operation range due to the hot residuals required to ignite the mixture and slow down reaction kinetics, only part-load operation is feasible in this combustion mode. Considering the future gasoline engine market with growing potentials identified in downsized gasoline engines, it becomes necessary to investigate the synergies and challenges of controlled, boosted HCCI.

Due to the increasingly stricter emission legislation and growing demands for lower fuel consumption, there have been significant efforts to improve combustion efficiency while satisfying the emission requirements. Homogeneous Charge Compression Ignition (HCCI) combined with turbo/supercharging on gasoline engines provides a particularly promising and, at the same time, a challenging approach. Naturally aspirated (n.a.) HCCI has already shown a considerable potential of about 14% in the New European Driving Cycle (NEDC) compared with a conventional 4-cylinder 2.0 liter gasoline Port Fuel Injection (PFI) engine without any advanced valve-train technology. The HCCI n.a. operation range is air breathing limited due to the hot residuals required for the self-ignition and to slow down reaction kinetics, and therefore is limited to a part-load operation area.

In recognition of safety considerations, modern fuel tanks are frequently extremely irregular in shape. This places limits on the application of conventional potentiometric sensors. Required are more universal sensors without mechanically-moving parts. These sensors should also be characterized by especially good resolution and precision in the residual-quantity range, that is, the zero point precision should be of a high order. One type of metal rod can be bent into any of a variety of shapes to provide an effective means of monitoring the fuel level. In this metal rod, the propagation characteristics of a certain type of sound wave, known as bending waves, display major variations according to the level of the surrounding medium: The waves spread more rapidly through the exposed section of the rod than through the area which remains submerged. Thus the rod's characteristic oscillation frequency varies as a function of immersion depth.

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.