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Acoustics and vibrations are amongst the foremost indicators in perceiving the quality of drive units. Analyzing these factors is vital for improve the performances of electro-mechanical systems. This paper deals with the study of vibro-acoustic behavior concerning the drivetrain components using system modeling and Finite Element calculations. A generic simulation methodology within system modeling is proposed enabling the vibro-acoustic simulation of electro-mechanical drivetrains. Excitations for these systems mostly arise from the electric motor and mechanical gears. The paper initially depicts the system model for gear whining considering the associated nonlinearities of the mesh. The results obtained from the gear mesh submodel, together with the excitations resulting from the motor, aid in the comprehension of the forces at the bearings and of the vibrations at the housings.

Fully Variable Valve Actuation (FVVA) systems enable to employ a wide range of combustion strategies by providing the actuation of a gas exchange valve at an arbitrary point in time, with variable lift and adjustable ramps for opening and closing. Making such a system ready for the market requires appropriate fault-diagnostic functionality. Here, we focus on diagnosis possibilities by using air intake system sensors such as Manifold Absolute Pressure (MAP) sensors. Results obtained on a 4-cylinder test bench engine are presented for the early intake opening strategy under different loads, and at medium range rotational speeds on steady-state conditions. It is shown that detection and identification of the different critical faults on each actuator is possible by using a Fourier series signal model of the MAP sensor.

This paper looks at the underlying fundamentals of diesel fuel system lubrication for the highly-loaded contacts found in fuel injection equipment like high-pressure pumps. These types of contacts are already occurring in modern systems and their severity is likely to increase in future applications due to the requirement for increased fuel pressure. The aim of the work was to characterise the tribological behavior of these contacts when lubricated with diesel fuel and diesel fuel treated with lubricity additives and model nitrogen and sulphur compounds of different chemical composition. It is essential to understand the role of diesel fuel and of lubricity additives to ensure that future, more severely-loaded systems, will be free of any wear problem in the field.

To achieve the future emissions regulations with low particulate and Nox levels, both the engine combustion system and the fuel injection equipment will have to be improved. For the fuel injection equipment, high injection pressure and variable injection timing as a function of engine speed, load, and temperature are of great importance. BOSCH is developing two different solutions: electronically controlled unit injector and single cylinder pump systems, high-pressure inline pumps with control sleeve and electronic control. This paper describes: the unit injector and its high-pressure solenoid valve the requirements for the mounting of the unit injector in the engine the low-pressure system the electronic control unit and the metering strategy

The conventional measurements to describe the photometric quality of headlamps usually only comprise the luminous flux and the illuminance (resp. the luminous intensity) in several measuring points given by Type Approval Legislation. Practically, these photometric measurements do not describe the visual impression of a headlamp light distribution sufficiently, neither in lab nor in real street geometry. With the clear outer lens headlamps introduced recently, filament images are projected directly onto the screens or streets, thus giving new impulses to research. Starting from the established photometric practice, other types of measurements and physiological fundamentals will be discussed. The basic tools to make physical measurement and physiological impression comparable, e.g. in terms of homogeneity, are shown.

Electromagnetic Compatibility (EMC) requirements and the effort to fulfill them are increasing steadily in automotive applications. This paper demonstrates the usage of virtual prototyping to efficiently investigate the EMC behavior of a gasoline direct injection system. While the system worked functionally as designed, tests indicated that current and especially future client-specific EMC limits could not be met. The goal of this investigation was to identify and eliminate the cause of EMC emissions using a virtual software prototype including the controller ASIC, boost converter, pi filter, injection valves and wire harness. Applying virtual prototyping techniques it was possible to capture the motor control system in a simulation model which reproduced EMC measurements in the frequency ranges of interest.

The reduction of nitrous oxides in the exhaust gases of internal combustion engines using a urea water solution is gaining more and more importance. While maintaining the future exhaust gas emission regulations, like the Euro 6 for passenger cars and the Euro 5 for commercial vehicles, urea dosing allows the engine management to be modified to improve fuel economy as well. The system manufacturer Robert Bosch has started early to develop the necessary dosing systems for the urea water solution. More than 300.000 Units have been delivered in 2007 for heavy duty applications. Typical dosing quantities for those systems are in the range of 0.01 l/h for passenger car systems and up to 10 l/h for commercial vehicles. During the first years of development and application of urea dosing systems, instantaneous flow measuring devices were used, which were not operating fully satisfactory.

Since 1996 a 2nd Generation EBS has been available in Europe as an advanced brake system offering a variety of advantages to the OEM as well as to the truck and fleet owner. EBS enhances vehicle safety and improves the braking performance to a “passenger car like” braking feel, allowing less experienced drivers better vehicle handling. The brake lining wear control and retarder integration allow the reduction of operational costs. The safety enhancements achieved by EBS in conjunction with disc brakes, are rewarded by European truck insurance companies by lower insurance fees. The importance of EBS will still gain significantly through the developments in process. EBS is the platform for ESP and ACC, which will be a major contributer to better integration of trucks in dense traffic flow.

With its origin in the process industry, the IEC 61508 „Functional safety of electrical/electronic/programmable electronic safety-related systems” is not fully applicable in the automotive industry, forcing the automotive industry to work on an automotive specific adaptation (ISO 26262 “Functional Safety – Road Vehicles”). This ISO 26262 describes an ideal development process that starts from scratch. In reality development activities are often split locally and in time. This can only be handled with a world wide standard as a basis of a common approach, wide enough to give enough freedom to adapt to diverse boundary conditions, but tight enough to hinder local interpretations to be that far, that a complete safety case becomes impossible. Therefore a strict world-wide standard which allows compatible interpretations is mandatory.

The demand for more security, economy, and comfort as well as for a reduced environmental impact increases the importance of electronic components for vehicles. The development of such systems is determined by the requirement of an improved functionality and co-requisite the demand for limited costs. In order to fulfil these demands and taking into consideration the increase of complexity and the melting together to a car wide web, Bosch is developing a structuring concept called CARTRONIC®. This concept is supposed to be open and neutral regarding automotive manufactures and suppliers. The analysis of vehicle control systems via this method is based on formal rules for structuring and modelling. The function-related aspect of CARTRONIC® was represented already at the SAE'98 World Congress. Furthermore the safety-related feature was introduced in more detail at the SAE'99 World Congress. The result of the analysis is an object structure of logical components with defined interfaces.

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).

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.

The Bosch Common Rail Fuel Injection System with the new technologies developed for the Duramax 6600 engine offer numerous performance advantages including exhaust emissions control and noise. The layout of the fuel system components and electrical parts is specifically designed to control fuel injection characteristics. The new injector and nozzle technology was integrated to achieve the required system performance. The new 1600bar fuel pump is also a prerequisite for required system performance.

Time Triggered CAN (TTCAN) is an extension of the well-known CAN protocol, introducing to CAN networks time triggered communication and a system wide global network time with high precision. Time Triggered CAN has been accepted as international standard ISOCD11898-4. The time triggered communication is built upon the unchanged standard CAN protocol. This allows a software implementation of the time triggered function of TTCAN, based on existing CAN ICs. The high precision global time however requires a hardware implementation. A hardware implementation also offers additional functions like time mark interrupts, a stopwatch, and a synchronization to external events, all independent of software latency times. The TTCAN testchip (TTCAN_TC) is a standalone TTCAN controller and has been produced as a solution to the hen/egg problem of hardware availability versus tool support and research.

In order to reduce the spark-ignition engine exhaust-gas emission and fuel consumption, it is essential that the required air/fuel ratio is maintained under all operating conditions. An important contribution to this claim is delivered by the injection valve by metering the fuel precisely and producing fine atomization. In this report experimental methods to get specific measuring information and methods for optimizing flow in injection valves are described. Original valves as well as large-scale models were used for the investigations concerning the steady and unsteady-flow characteristics, and were equipped with a number of different sensors. Holograms of the short-time recording of the spray cone are generated and used for the quantification of the atomization quality when injecting into atmospheric pressure and into vacuum, thus complying with the conditions encountered in the engine intake-manifold.

To satisfy future emission classes, e.g. EU6c, the particulate number (PN) of Direct-Injection Spark-Ignition (DISI) engines must be reduced. For these engines, different components influence the combustion process and thus also the formation of soot particles and deposits. Along with other engine components, the injector nozzle influences the particulate number and deposits in both fuel spray behavior and nozzle “tip wetting”. In case of non-optimized nozzle layouts, fuel may impinge on the piston and the liner in an unfavorable way, which implies low-oxygen diffusive combustion by retarded vaporizing wall films. For the tip wetting, wall films are present on the actual surface of the nozzle tip, which is also caused by unadapted nozzles. For non-optimized nozzles, the latter effect can become quite dominant. This paper deals with systematic nozzle development activities towards low-deposit nozzle tips and thus decreasing PN values.

Many software functions currently available in the engine control units have been developed for several years (decades in some cases), reengineered or adapted due to new requirements, what may add to their inherent complexity an unnecessary complication. This paper deals with the study and implementation of a software reengineering strategy for the embedded domain, which is in transfer from research department to product development, here applied to improve maintainability of flex fuel functions. The strategy uses the SCODE “Essential Analysis”, an approach for the embedded system domain. The method allows to reduce the system complexity to the unavoidable inherent problem complexity, by decomposing the system into smaller sub problems based on its essential physics. A case study was carried out to redesign a function of fuel adaptation. The analysis was performed with the support of a tool, which covers all the phases of the method.

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.

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.

The fuel spray behavior in the near nozzle region of a gasoline injector is challenging to predict due to existing pressure gradients and turbulences of the internal flow and in-nozzle cavitation. Therefore, statistical parameters for spray characterization through experiments must be considered. The characterization of spray velocity fields in the near-nozzle region is of particular importance as the velocity information is crucial in understanding the hydrodynamic processes which take place further downstream during fuel atomization and mixture formation. This knowledge is needed in order to optimize injector nozzles for future requirements. In this study, the results of three experimental approaches for determination of spray velocity in the near-nozzle region are presented. Two different injector nozzle types were measured through high-speed shadowgraph imaging, Laser Doppler Anemometry (LDA) and X-ray imaging.