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Regarding the strongly growing two-wheeler market fuel economy, price and emission legislations are in focus of current development work. Fuel economy as well as emissions can be improved by introduction of engine management systems (EMS). In order to provide the benefits of an EMS for low cost motorcycles, efforts are being made at BOSCH to reduce the costs of a port fuel injection (PFI) system. The present paper describes a method of how to reduce the number of sensors of a PFI system by the use of sophisticated software functions based on high-resolution engine speed evaluation. In order to improve the performance of a system working without a MAP-sensor (manifold air pressure sensor) an air charge feature (ACFn) based on engine speed is introduced. It is shown by an experiment that ACFn allows to detect and adapt changes in manifold air pressure. Cross-influences on ACFn are analyzed by simulations and engine test bench measurements.

The increasing number of electronic control units (ECUs) in vehicles leads to more and more complex systems with a steadily growing demand for data exchange. This growth includes the number of bus participants, the amount of data and hence the data transfer rates. In addition, the trend towards car-to-x connectivity reinforces the need for new in-vehicle communication solutions. Since the early 1990s Controller Area Network (CAN) is the most widely used powertrain bus system. Since 2000 FlexRay is used in addition to CAN in the premium segment. For classic powertrain applications, the data transfer rates of these bus systems are sufficient; however the utilization is sometimes difficult and gateways are often required. For new applications like hybrid and electric vehicles and the next generation of external communication applications (e.g. telematics services) new concepts based on the existing bus systems or completely new solutions are needed.

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.

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.

In order to master the increasing complexity of electrical/electronic (E/E) systems in vehicles, E/E architecture design has become an established discipline. The task of the E/E architecture design is to come up with solutions to challenging and often contradictory requirements such as reduced cost and increased flexibility / scalability. One way to optimize the E/E architecture in terms of cost (electronics & wiring harness) is to integrate functions. This can be done by either combining functions from multiple ECUs into a single ECU or by introducing Domain Control Units. Domain Control Units provide the main software functionality for a vehicle domain, while relegating the basic functions of actuator control to connected intelligent actuators. Depending on the different market segments (low price, volume and premium) and the different vehicle domains, the actual usage of Domain Control Units can be quite different and sometimes questionable.

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.

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.

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.

To meet future CO₂ emissions limits and satisfy the bounds set by exhaust gas legislation reducing the engine displacement while maintaining the power output ("Downsizing") becomes of more and more importance to the SI-engine development process. The total number of cylinders per engine has to be reduced to keep the thermodynamic disadvantages of a small combustion chamber layout as small as possible. Doing so leads to new challenges concerning the mechanical design, the design of the combustion system concept as well as strategies maintaining a satisfying transient torque behavior. To address these challenges a turbocharged 2-cylinder SI engine with gasoline direct injection was designed for research purposes by Weber Motor and Bosch. This paper wants to offer an insight in the design process. The mechanical design as well as the combustion system concept process will be discussed.

The 2011 Report of Ministry of Road Transport and Highways, Government of India states that the total accidents with injuries is estimated about 497, 686 out of which the injuries are 511, 394 and fatalities are 142, 485, an average of one fatality per 3.5 [1]. Social losses on account of these crashes are estimated at over Rupees 100 000 Crores annually or 3% of our Gross Domestic Product (GDP) [2]. The irony is that these causalities are rising at 5.9 % annually. India accounts for 10% of the global road crash fatalities. Therefore traffic safety became very important in India. In order to understand the root causes of accidents data is needed in more detail which could be analyzed and points out the major issues to find solutions to stop this trend. Besides vehicle safety, infrastructure related issues and education skills can be derived out of accident data. Official statistics regarding accidents in India are available in national and state wise reports.

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.

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).

In order to optimize the inner flow of the regenerative pump used in gasoline injection systems, we carry out experimental and numerical flow investigations. A qualitative analysis of spatial flow phenomena in selected regions of the pump is presented by employing the laser light sheet technique. Therefore, a tenfold enlarged water model is built up, where dynamic similarity with the original flow is achieved. The results of the flow analysis have led to improved geometries which are compared with the original design by measured pump characteristic curves. Furthermore, three-dimensional simulations of the fully developed turbulent flow using a finite-element method are presented. The flow with respect to the rotating impeller is calculated by solving the Reynolds equations in connection with the k-ε-turbulence model.

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.

This paper describes the concept of the operating system ERCOS (Embedded Real-time Control Operating System). ERCOS has been specially designed to meet the functionality and performance requirements in the area of automotive applications. The ever increasing functional requirements for modern electronic control units are introducing considerable complexity in the area of software development. It is well known that real-time operating systems provide powerful means to handle complex functions under real-time constraints. Past experience, however, has shown that the efficiency and flexibility of operating systems was very often inadequate for automotive applications. To overcome these insufficiencies the operating system ERCOS has been designed with dedicated support for automotive requirements. This has been achieved by supplementing the run-time part of the operating system by powerful off-line tools.

As new smart systems for passenger cars are assisting me driver to handle manoeuvres in critical and normal situations, brake systems are required to fulfill the compatibility and interface demands. These advanced brake systems will be operated in a remote mode during normal braking and for autonomous brake interventions. BOSCH is developping a brake-by-wire system on a hydraulic basis, called ‘Electrohydraulic Brake EHB’. Brake pressure buildup is supplied by a high pressure accumulator. Generation of the high pressure is done by an electric motor driven pump, similar to current ABS-systems. Pressure at the wheel brakes is individually controlled by closed-loop pressure control, consisting out of inlet, and outlet valves, pressure sensor and corresponding algorithm. It is specified, that this control must be completely noiseless, proportional, fast, and highly accurate. To raise the acceptance of such a system, it will be introduced with a conventional hydraulic backup.

The continuing increase in the performance of restraint systems has led to a drastic increase in the number of actuator devices. The individual wiring of the igniters becomes more and more problematic through the accompanied large number of plug connections and cables. Along with demands for weight and volume reduction, there are requirements for EMI and short circuit protection to eliminate erroneous deployment and misuse. As a solution, a new multi-protocol dual wire bus system is described that has the capability to supply energy and address multiple peripheral output stages to simultaneously fire any combination of actuators.

The Bosch ABS for passenger cars which has been in production since 1978 has been described in numerous publications. Following the gathering of extensive experience with the Bosch ABS and its installation in the different models of passenger car, the concept has been revised with various upgrade levels in order to further optimize braking performance on µ-split road surfaces with different right/left adhesion coefficients, in order further to improve the operation of the system when braking on very slippery road surfaces and also to adapt the control algorithm to four-wheel-drive vehicles with differential locks.