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Nowadays automobiles are getting smart and there is a growing need for the physical behavior to become part of its software. This behavior can be described in a compact form by differential equations obtained from modeling and simulation tools. In the offline simulation domain the Functional Mockup Interface (FMI) [3], a popular standard today supported by many tools, allows to integrate a model with solver (Co-Simulation FMU) into another simulation environment. These models cannot be directly integrated into embedded automotive software due to special restrictions with respect to hard real-time constraints and MISRA compliance. Another architectural restriction is organizing software components according to the AUTOSAR standard which is typically not supported by the physical modeling tools. On the other hand AUTOSAR generating tools do not have the required advanced symbolic and numerical features to process differential equations.

This paper presents the Vehicle Dynamics Control (VDC) for commercial vehicles developed by BOSCH. The underlying physical concept is discussed in the second section after a short introduction. The third section shows the computer simulation used in the development process. Section four describes the controller structure of the VDC system. In Section five the use and effectiveness of VDC for commercial vehicles is shown in different critical driving situations. This is done by using measured data collected during testing (lane change, circular track) and it demonstrates that the safety improvements achieved for passenger cars are also possible for commercial vehicles.

Innovative solutions for reducing particulate emissions will be necessary in order to comply with the even more stringent exhaust-gas standards of the future. The potential of a diesel nozzle with variable orifice geometry has long been common knowledge in the area of engine construction. But up to now, a fully functional solution of such a nozzle has not appeared which operates with a reduced orifice at low engine speeds and/or low loads. Here with regard to target costing, the requirements implicit in function and manufacture must also be taken into account. Using calculations on nozzle interior flow and injection-spray investigations, it will be shown which nozzle geometries best fulfill the various requirements. In order to achieve low levels of particulate emission in an engine with a combustion chamber designed for optimum use of a hole-type nozzle, the injection-spray direction and its geometry must to a large extent correspond to those of a hole-type nozzle.

Since its introduction in March 1995, the market demand for Vehicle Dynamic Control systems (VDC) has increased rapidly. Some car manufacturers have already announced their plans to introduce VDC on all their models. Particularly for compact and subcompact cars the system price needs to be reduced without sacrificing safety and performance. Originally designed for optimal performance with economically feasible components (sensors, hydraulics and microcontrollers) and using a unified control approach for all vehicle operating situations the system has been extended to include various drive concepts and has continuously been improved regarding performance, safety and cost. This paper describes the progress made in the development of the Bosch VDC system with regard to the design of the hydraulic system, the sensors, the electronic control unit, the control algorithm and safety.

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.

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.

The manufacturers of passenger cars increasingly assign development and production of complete subsystems to the supplying industry. A brake system supplier has to give predictions about system quality and performance long time before the first prototypical system is built or even before the supplier gets the order for system development. Nowadays, the usage of computer-aided system design and simulation is essential for that task. This article presents a tool designed to support the development process. A special focus will be on how to define quality. A formal definition of quality is provided, illustrated and motivated by two examples.

Novel Combustion technologies and strategies show high potential in reducing the fuel consumption of gasoline spark ignition (SI) engines. In this paper, a comparison between various gasoline combustion concepts at two representative engine operating points is shown. Advantages of the combustion concepts are analyzed using thermodynamic split of losses method. In this paper, a tool for thermodynamic assessment (Split of Losses) of conventional and new operating strategies of SI engine and its derivatives is used. Technologies, like variable valve actuation and/or gasoline direct injection, allow new strategies to run the SI engine unthrottled with early inlet valve closing (SI-VVA) combined with high EGR, charge stratification (SI-STRAT) and controlled auto ignition (CAI), also known as gasoline homogeneous charge compression ignition (HCCI). These diverse combustion concepts show thermodynamic gains that stem from several, often different sources.

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.

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 range of Robert Bosch in-line pumps is designed for engines with cylinder outputs of up to 200 kW. Within this family of pumps the MW pump is used in small IDI engines and medium-sized DI engines with cylinder outputs in the region of 30 kW. More stringent exhaust emission legislation and the need to ensure optimum fuel economy call for efficient fuel-injection systems for diesel engines. In both of its designs the new MW pump meets these more exacting requirements and forms the contribution of Robert Bosch GmbH toward developing advanced diesel engines.

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.

The hydro grinding process can be used for valve covered orifice (VCO) nozzle production. A comprehensive numerical and experimental investigation was performed to determine the influence of hydro grinding (HG) at VCO nozzles on the mixture preparation in pressure charged high speed direct injection diesel engines. Samples of five hole VCO nozzles with defined grades of HG and different sprayhole diameters were selected to ensure a constant mass flow at a fixed feeding pressure for comparable engine tests. The simulation of the internal flow shows a more symmetrical velocity profile indicating less shear flow and lower turbulence intensities at the orifice with increased HG grade. From these results an enhanced atomization at further penetration depth and reduced atomization close to the nozzle could be expected. This was confirmed by measuring the spray momentum distribution and spray tip speed by mechanical and optical probes in high pressure vessels.

A previous study by the authors has shown an efficiency benefit of up to Δηi = 10 % for stratified operation of a high pressure natural gas direct injection (DI) spark ignition (SI) engine compared to the homogeneous stoichiometric operation with port fuel injection (PFI). While best efficiencies appeared at extremely lean operation at λ = 3.2, minimum HC emissions were found at λ = 2. The increasing HC emissions and narrow ignition time frames in the extremely lean stratified operation have given the need for a detailed analysis. To further investigate the mixture formation and flame propagation und these conditions, an optically accessible single-cylinder engine was used. The mixture formation and the flame luminosity have been investigated in two perpendicular planes inside the combustion chamber.

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.

The hydrogen engine is one of the promising technologies that enables carbon-neutral mobility, especially in heavy-duty on- or off-road applications. In this paper, a methodological procedure for the design of the combustion system of a hydrogen-fueled, direct injection spark ignited commercial vehicle engine is described. In a preliminary step, the ability of the commercial 3D computational fluid dynamics (CFD) code AVL FIRE classic to reproduce the characteristics of the gas jet, introduced into a quiescent environment by a dedicated H2 injector, is established. This is based on two parts: Temporal and numerical discretization sensitivity analyses ensure that the spatial and temporal resolution of the simulations is adequate, and comparisons to a comprehensive set of experiments demonstrate the accuracy of the simulations. The measurements used for this purpose rely on the well-known schlieren technique and use helium as a safe substitute for H2.

Surround sensing methods provide information which can be used in PRECRASH functionalities for advanced control of the passenger protection system. The relevant data (closing velocity (cv), time to impact (tti), and offset of contact point (Δy)) are determined with a Predictive Safety System and transmitted to the airbag control unit for further processing in the PRECRASH algorithm. The PRECRASH algorithm controls both, the activation of reversible restraints and the deployment of irreversible restraints. Therefore it consists of two components: The PREFIRE and the PRESET algorithm. The PREFIRE algorithm uses the PRECRASH information for the activation of the reversible belt pretensioner in advance of a crash to reduce chest load in the crash phase. The PRESET algorithm calculates the trigger decision for deployment of pyrotechnical restraints. Inputs of the PRESET algorithm are the PRECRASH information as well as the acceleration signal.

The stricter worldwide emission legislation and growing demands for lower fuel consumption and CO2-emission require for significant efforts to improve combustion efficiency while satisfying the emission quality demands. Ethanol fuel combined with boosting on direct injection gasoline engines provides a particularly promising and, at the same time, a challenging approach. Brazil is one of the main Ethanol fuel markets with its E24 and E100 fuel availability, which covers a large volume of the national needs. Additionally, worldwide Ethanol availability is becoming more and more important, e.g., in North America and Europe. Considering the future flex-fuel engine market with growing potentials identified on downsized spark ignition engines, it becomes necessary to investigate the synergies and challenges of Ethanol boosted operation. Main topic of the present work focuses on the operation of Ethanol blends up to E100 at high loads up to 30 bar imep.

Fuel economy of two-wheelers is an important factor influencing the purchasing psychology of the consumer within the emerging markets. Additionally, air pollution being a major environmental topic, there is a rising concern about vehicle emissions, especially in the big cities and their metropolitan areas. Potentially, the relatively expensive engine management systems are providing more features and value in comparison to the carburettor counterpart. The combustion system analysis is carried out on a 125 cm3 motorcycle engine and the subsequent numerical simulation comparing the carburettor and the Electronic (Port) Fuel Injection which provides a basis to establish the fuel consumption benefit for the electronic injection systems [1].

Two-dimensional Mie and LIEF techniques were applied to investigate the spray formation of a high pressure gasoline swirl injector in a constant volume chamber. The results obtained provide information on the propagation of liquid fuel and fuel vapor for different fuel pressures and ambient conditions. Spray parameters like tip penetration, cone angles and two new defined parameters describing the radial fuel distribution were used to quantify the fuel distributions measured. Simultaneous detection of liquid and vapor fuel was applied to study the influence of ambient temperature, injector temperature and ambient pressure on the evaporating spray.