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An electronic control of throttle angle is required for safety systems like traction control (ASR) and for advanced engine management systems with regard to further improvements of driving comfort and fuel economy. For applications, in which only ASR is required, two versions of a new traction control actuator (TCA) have been developed. Their function is based on controlling the effective length of the bowden cable between the accelerator pedal and the throttle. Besides retaining the mechanical linkage to the throttle, the concept has no need for a pedal position sensor, which is necessary for a drive-by-wire system. Design and performance of both actuators are described and their individual advantages are compared. Moreover, the communication of the system with ASR and its behaviour with regard to vehicle dynamics are illustrated.

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.

Software-in-the-Loop (SiL) test environments are the ideal virtual platforms for enabling continuous-development, -integration, -testing -delivery or -deployment commonly referred as Continuous-X (CX) of the complex functionalities in the current automotive industry. This trend especially is contributed by several factors such as the industry wide standardization of the model exchange formats, interfaces as well as architecture definitions. The approach of frontloading software testing with SiL test environments is predominantly advocated as well as already adopted by various Automotive OEMs, thereby the demand for innovating applicable methods is increasing. However, prominent usage of the existing monolithic architecture for interaction of various elements in the SiL environment, without regarding the separation between functional and non-functional test scope, is reducing the usability and thus limiting significantly the cost saving potential of CX with SiL.

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.

Since introduction of safety belts in the 70s and airbags in the early 80s, these passive safety technologies have become standard in many markets. Remarkable improvement in passive safety, efforts to alter driver behaviour and infrastructural programmes have led to substantial reductions of fatalities in many regions, although the absolute number of highway fatalities increased e.g. in the USA in 2002 to the highest level since 1990. Electronic Stability Control (ESC) as an active safety technology assists the driver to keep the vehicle on the intended track and thereby actively prevents accidents. In 1995 Bosch was the first supplier to introduce ESC for the Mercedes-Benz S-Class, where it is marketed as ESP® - Electronic Stability Program. Since then, Bosch has produced more than 30 million systems worldwide. Many studies have now confirmed that ESC can prevent a vehicle from skidding or rolling over in nearly all driving situations.

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.

ABS has proven to be a contribution to active safety. The introduction of traction control (TC) in 1986 and even more significantly, the introduction of vehicle dynamics control (VDC) in 1995 have been further milestones in this field. The functionality of these systems (ABS, TC, VDC) is mainly determined by the electronic control unit (ECU). A system supplier who is to provide an ECU-platform concept including a large functionality, while meeting customer specific requirements at an optimized price, needs standardization strategies. This paper describes a standardization concept for an ABS ECU, beginning with the basic ABS HW and SW design and the extension to TC and VDC. It also shows the degree of flexibility, the benefits for the vehicle manufacturer and the possible cost optimization for the system supplier.

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.

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.

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.

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.

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.

During the acquisition phase brake system supplier have to make predictions on a system's thermal behavior based on very few reliable parameters. Increasing system knowledge requires the usage of different calculation models along with the progress of the project. Adaptive modeling is used in order to integrate test results from first prototypes or benchmark vehicles. Since changes in the brake force distribution have a great impact on the simulation results fading conditions of the linings have to be integrated as well. The principle of co-simulation is used in order to use the actual brake force distribution of the system.

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.

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.

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.

Traction control (ASR) is the logical ongoing development of the antilock braking system (ABS). Due to the high costs involved though, the widespread practice of reducing the engine power by electronic throttle control (or electronic enginepower control) has up to now prevented ASR from becoming as widely proliferated as ABS. A promising method has now been developed in which fuel-injection suppression at individual cylinders is used as a low-price actuator for a budget-priced ASR. First of all, an overview of the possibilities for influencing wheel-torque by means of intervention at the engine and/or brake as a means of reducing driven wheel slip is presented. Then, the system, the control strategy, and the demands on the electronic engine-management system with sequential fuel injection are discussed. The system's possibilities and its limitations are indicated, and fears of damaging effects on the catalytic converter are eliminated.

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.

Since the brake colloquium in 2004 the role of climatic conditions and their relations to noise occurrence, sound pressure level and friction coefficient level is widely discussed in the US and European working groups on brake noise. A systematic study has been started to investigate the influence of relative humidity, absolute humidity and temperature on brake noise and the corresponding friction coefficient level. In this study an enormous effort was taken to keep the influences of the brake parameters, e.g. lining material, Eigenfrequencies and dimensions of the different components as small as possible to investigate the climatic influence only. Strategic humidity and temperature levels were tested according to the Mollier-Entropy-Enthalpy-Diagram which are corresponding to the seasons in the various international regions. A regression analysis evaluates the correlation and the influence of each parameter to noise and friction coefficient level.

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.