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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.

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 development of vehicle communication networks is challenged not only by the increasing demand in data exchange and required data rate but also the need to connect the vehicle to external sources for personal connectivity of driver and car to infrastructure applications. Solutions are required to master complexity of in-vehicle communication networks, e.g. diagnostic access, flashing of Electronic Control Units, the data backbone connecting the vehicle domains and the data transfer of cameras. Safety (data transfer) and security (violation) issues of the communication networks gain more importance especially by introducing interfaces to external sources either via mobile devices or by connecting the vehicle to other external sources, e.g. Internet and Car to Infrastructure applications. The Internet Protocol (IP) appears to be an ideal solution to address these challenges, especially in connection with an Ethernet physical layer for fast data transfer.

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.

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.

AUTOSAR (AUTomotive Open System ARchitecture) is a worldwide standard for automotive basic software in line with an architecture that eases exchange and transfer of application software components between platforms or companies. AUTOSAR provides the standardized architecture together with the specifications of the basics software along with the methodology for developing embedded control units for automotive applications. AUTOSAR matured over the last several years through intensive development, implementation and maintenance. Two main releases (R3.2 and R4.0) represent its current degree of maturity. AUTOSAR is driven by so called core partners: leading car manufacturers (BMW, Daimler, Ford, GM, PSA, Toyota, Volkswagen) together with the tier 1 suppliers Continental and Bosch. AUTOSAR in total has more than 150 companies (OEM, Tier X suppliers, SW and tool suppliers, and silicon suppliers) as members from all over the world.

This paper presents the conceptual model and the fundamental mechanisms for software development in the context of the Brite-EuRam project Safety Related Fault Tolerant Systems in Vehicles (nick-named X-By-Wire). The objective of the X-By-Wire project is to achieve a framework for the introduction of safety related fault tolerant electronic systems without mechanical backup in vehicles. To achieve the required level of fault-tolerance, an X-By-Wire system must be designed as a distributed system comprising a number of fault-tolerant units connected by a reliable real-time communication system. For the communication system, the time-triggered TTP/C real-time communication protocol was selected. TTP/C provides fault-tolerance message transfer, state synchronization, reliable detection of node failures, a global time base, and a distributed membership service. Redundancy is used for masking failures of individual processor nodes and hardware peripherals.

The car industry has reached a point where electronic systems, which were so far essentially autonomous, begin to grow together to a Car-Wide Web. The main driving force is the demand for more safety, security, and comfort implemented economically. Already various parties are working on control networks. In the long run, vehicle motion and dynamic systems, safety, security, comfort as well as mobile multimedia systems will integrate and reach out for the vision of accident-free, comfortable, and well-informed driving. As a foundation for a Car-Wide Web, Bosch is developing an open architecture called CARTRONIC. The essence of CARTRONIC is to define structuring rules, modeling rules and patterns for total, integrated control of vehicles. The rules and patterns allow the mapping of high-level functions onto several physical implementations, for instance one logical description of functional connections could be created for cars with different equipment packages.

Signals in Automotive Communication Networks often represent safety relevant information. Therefore, automotive network protocols provide multiple powerful mechanisms for error detection and for error reporting. The objective is to ensure that on average less than one undetected error occurs during the lifetime of a vehicle. This places an upper bound on the residual error probability of the communication network. The determination of this residual error probability requires new methods in order to account for the interaction of the various error detection mechanisms. This paper presents an analysis method that has been developed for the investigation of the CAN protocol. This comprehensive investigation distinguishes two types of errors that contribute most significantly to the residual error probability of the CAN protocol. Errors of one type transform stuffbits into information bits or vice versa, and are related to the use of variable bit stuffing.

This address presents the ongoing development of the commercial-vehicle braking system, over and beyond ABS/ASR, towards a brake by wire system (electronically controlled braking system ELB) with pressure-regulating circuit and additional functions. Following the discussion and selection of various concepts, we will present different versions with individual and combined components for the towing vehicle and for the trailer. The safety concept of a pneumatic back-up circuit will be dealt with, as well as the communication through data bus (CAN) both within the braking system itself and with other vehicle systems. The improvement possibilities inherent in ELB will be detailed, with the emphasis on increasing road and traffic safety, on reducing operating costs, and on future vehicle-guidance functions.

Serial communication by means of CAN is being used more and more for data transfer between in-vehicle control units to link components of the drive train, body electronics and mobile communication electronics. In order to design distributed electronic systems, software engineers today must not only develop the application software but also supply the communication software to handle the communication hardware, thereby reinventing the wheel with each new application software package. This procedure is inefficient as it leads to hardly reusable special solutions. To avoid incompatibilities between the modules of a distributed system a lot of additional coordination work must be done during the design phase. As a consequence, each new software package is faced with additional costs for the indispensible tests of the communication software. This paper describes a network architecture that has been designed for CAN systems.

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.

This paper describes the architecture and the implementation of a software for the communication between networked in-vehicle ECUs. The communication software is based upon a real-time multitasking operating system. The operating system and the communication software form an application-independent platform for the implementation of distributed ECU software. The software architecture consists of several communication layers and a station management module. The communication layers provide network driver, data transfer services and an application interface that is independent of the used network protocol. The station management module is responsible for configuration and initialization of the communication controller, error detection during operation and error handling. The modula r structure of the architecture supports the simple adaptation of the software to different bus systems and communication controllers.

Modern agricultural tractors are equipped with a hitch control system. These may be mechanical-hydraulic, hydraulic-hydraulic, or electronic-hydraulic. With the variety of design options open to the tractor manufacturer, it is important to select the system which best fits the manufacturer and end user. This paper presents a comprehensive comparison of each system. Robert Bosch has had many years experience in the design and manufacture of components for hitch systems, and hopes to help designers choose the approach best suited for them.

Electronic systems have been used in commercial vehicles for quite a few years now. At the start, this primarily related to consumer electronics equipment (car radio and CB radio), but, since the late 70s, electronic control systems have also been used for a wide variety of applications in commercial vehicles. This development went hand in hand with the development of digital microcontrollers. It was only when such powerful electronic circuits were developed that it was possible to implement complex control tasks at feasible cost with adequately compact design. Nowadays, an extremely wide variety of systems is offered for the engine, suspension, brakes, comfort and entertainment.

Commercial vehicles must convey people and goods safely and reliable, irrespective of the weather and road conditions. The ABS safety braking systems are an essential prerequisite for fulfillment of this primary task. ABS has been used in European commercial vehicles since 1981. Today there are already fittet as standard in buses to some extend. The contribution to increasing road safety is causing the European lawmakers to make ABS statutory for commercial vehicles and to make it part of their compulsory equipment. Suitable anti-lock braking systems and closed loop configurations for commercial vehicles are demonstrated by theoretical observations and technical driving trials, their axlespecific and closed-loop control characteristics are highlighted.

High performance Antilock Braking Systems (ABS) are well known to allow for very rapid pressure changes in the wheel brake cylinders. Recordings of the wheel speed during ABS control show oscillations just after the rapid pressure changes. The oscillations can not be explained by simulation if the usual stationary brake force versus slip curves are used. Thus the investigation of the oscillations requires a different approach to the modelling of the tire. As a first step in the alternative modelling of the tire the forces and moments on the running tire were measured using an experimental car. During the measurement the pressure in the wheel brake cylinder was modulated stepwise. A new Rotating Wheel Dynamometer was used to take those measurements. The results showed that the oscillations which were observed in the wheel speed could also be found in the braking force on the tire. Contrarily, the corresponding oscillations could not be found in the braking torque.

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.