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This paper describes challenges and possible solution of hybrid electrical vehicles test systems with a special focus on hardware-in-the-loop (HIL) test bench. The degree of novelty of this work can be seen in the fact that development and test of ECU for hybrid electrical powertrains can move more and more from mechanical test benches with real automotive components to HIL test systems. The challenging task in terms of electrical interface between an electric motor ECU and an HIL system and necessary real-time capable simulation models for electric machines have been investigated and partly solved. Even cell balancing strategies performed by battery management systems (BMU) can be developed and tested using HIL technology with battery simulation models and a precise cell voltage simulation on electrical level.

Hardware-in-the-loop (HIL) simulation is a real-time testing process that has been proven indispensable for the modern vehicle dynamics, powertrain, chassis and body systems electronic controls development. The high quality standards and robustness of the control algorithms can only be met by means of detailed vehicle plant simulation models. In the last few years, several efforts have been made to develop detailed plant models. Several tools for the vehicle modeling are available in the market and each tool has different and distinct advantages. This paper addresses ways that dSPACE Automotive Simulation Models (ASM) can support the model-based development processes. Additional modern software tools that were used in connection with the ASM are LMS AMESim and Mathworks SimDriveline (of Simscape). ASM is an open Matlab/Simulink model environment used for offline PC based simulation and online real-time platform HIL testing.

1 A recent breakthrough in understanding the origin of ion signals from operating combustion engines [12] led to a new approach in integrating advanced ion current sensing into a compact ignition system. Thus it is now possible to continuously monitor mixture, ignition and combustion properties through online ion current recordings via a novel AC technique. In this paper this AC technique is compared to the standard DC technique and its known drawbacks: expensive high voltage components, sensitivity to plug fouling and expensive electronics. The AC technique is based on the specific properties of the electrical field of spark plugs being characterized by a point source with an extreme inhomogeneity of the electrical field due to the small center electrode. This causes a distinct diode characteristic of the ion signal: very low signals for negative voltages and high signals for positive ion sensing voltages, respectively.

This paper discusses the standards that can currently be applied to production code generators and examines five standards in detail: OSEK/VDX, MISRA C, ISO/IEC 15504 (SPiCE), which is compared to ‘CMM for Software’, and IEC 61508. The issues involved in meeting these standards or integrating them in production code generators are discussed. The suitability of automatic production code generation in safety-critical applications is described, taking the TargetLink production code generator from dSPACE as an example.

In response to ever more stringent emission limits (EURO IV, SULEV), engine developers are increasingly turning their attention to engine start-up and warm-up phases. Since in this phase the catalytic converter has not yet reached its operating temperature, problems occur especially with regard to hydrocarbon emissions (HC) which are emitted untreated. Secondary air injection represents one option for heating up the catalytic converter more quickly. The engine is operated during the heating up cycle with retarded ignition angles and a rich mixture. Ambient air (secondary air) is injected close to the exhaust valve seat. During the spontaneously occurring post oxidation phase, the reactive exhaust components ignite and heat up the catalytic converter while simultaneously reducing HC. The various processes which affect the post oxidation, are not well known up to now. In order to achieve concrete improvements, detailed knowledge of its influences are necessary.

Model-based development and autocoding have become common practice in the automotive industry over the past few years. The industry is using these methods to tackle a situation in which complexity is constantly growing and development times are constantly decreasing, while the safety requirements for the software stay the same or even increase. The debate is no longer whether these methods are useful, but rather on the conditions for achieving optimum results with them. From the experiences made during the last decade this paper shows some of the key factors helping to achieve success when introducing or extending the deployment of automatic code generation in a model-based design process.

Today's interior systems engineer has been challenged with providing cost-effective instrument panel design solutions to meet NHTSA's new FMVSS 208 front crash regulations. Automotive manufacturers are in continuous search of newer methods and techniques to reduce prototype tests and cost. Analytical methods of predicting occupant and structural behavior using computer-aided engineering (CAE) analysis has been in place for quite some time. With the new FMVSS 208 regulations requiring both 5th and 50th percentile occupant testing, CAE analysis of predicting occupant response has become increasingly important. The CAE analyst is challenged with representing the barrier test condition, which involves the structure and the occupant moving at velocities of 25, 30 and 35 mph. Representing the cab kinematics in high-speed impacts is crucial, since capturing the vehicle intrusion and pitching should be made part of the input variables.

Mercedes-Benz at DaimlerChrysler has been developing and applying Life-Cycle-Engineering (LCE) and Life-Cycle-Assessment (LCA) since almost 10 years. Extensive experience and know-how has been gained by two complete car LCAs and more than 100 LCAs for parts. According to our experience LCA/LCE is most effectively and efficiently used to support the development of new products. One of DaimlerChrysler's Environmental Guidelines includes a statement, that our approach to environmentally acceptable design covers the entire product spectrum of the DaimlerChrysler Group, taking into account the product life cycle from design through disposal or recycling. The organisation of environmental management at DaimlerChrysler has a distinct structure of tasks: the central Environmental Protection Division coordinates all organisation/ plant related aspects, while all product related aspects are the responsibility of the divisonal business units.

After-treatment systems (ATS) consisting of new catalyst technologies and particulate filters will be necessary to meet increasingly stringent global regulations limiting particulate matter (PM) and NOx emissions from heavy duty and light duty diesel vehicles. Fuels and lubes contain elements such as sulfur, phosphorus and ash-forming metals that can adversely impact the efficiency and durability of these systems. Investigations of the impact of lubricant formulation on the transfer of ash-forming elements to diesel particulate filters (DPF) and transfer of sulfur to NOx storage catalysts were conducted using passenger car diesel engine technology. It was observed that for ATS configurations with catalyst(s) upstream of the DPF, transfer of ash-forming elements to the DPF was significantly lower than expected on the basis of oil consumption and lube composition. Sulfur transfer strongly correlated with oil consumption and lubricant sulfur content.

In this article model-based controller design techniques are investigated for the transient operation of a common-rail diesel engine in order to optimize driveability and to reduce soot emissions. The computer-aided design has benefits in reducing controller calibration time. This paper presents a nonlinear control concept for the coordinated control of the exhaust gas recirculation (EGR) valve and the variable geometry turbocharger (VGT) in a common-rail diesel engine. The overall controller structure is set up to regulate the total cylinder air-charge with a desired fresh air-charge amount by means of controlling the intake manifold pressure and estimating the fresh air-charge inducted into the cylinders. During varying engine operating conditions the two control loops are coordinated by a compensation of the EGR valve action through the VGT controller.

Model-based development is the established way of developing embedded control algorithms, especially for safety-critical applications. The aim is to improve development efficiency and safety by developing the software at a high abstraction level (the model) and by generating the implementation (the C code) automatically from the model. Although model-based development focuses on the models themselves, downstream artifacts such as source code or executable object code have to be considered in the verification stage. Safety standards such as ISO 26262 require upper bounds to be determined for the required storage space or the execution time of real-time tasks, and the absence of run-time errors to be demonstrated. Static analysis tools are available which work at the code level and can prove the absence of such errors. However, the connection to the model level has to be explicitly established.

Permanently increasing software complexity of today's electronic control units (ECUs) makes testing a central and significant task within embedded software development. While new software functions are still being developed or optimized, other functions already undergo certain tests, mostly on module level but also on system and integration level. Testing must be done as early as possible within the automotive development process. Typically ECU software developers test new function modules by stimulating the code with test data and capturing the modules' output behavior to compare it with reference data. This paper presents a new and systematic way of testing embedded software for automotive electronics, called MTest. MTest combines the classical module test with model-based development. The central element of MTest is the classification-tree method, which has originally been developed by the DaimlerChrysler research department.

This paper presents an overview of a project called “Modelling and Simulation Tools for Systems Integration on Aircraft (MISSION)”. This is a collaborative project being developed under the European Union Clean Sky 2 Program, a public-private partnership bringing together aeronautics industrial leaders and public research organizations based in Europe. The provision of integrated modeling, simulation, and optimization tools to effectively support all stages of aircraft design remains a critical challenge in the Aerospace industry. In particular the high level of system integration that is characteristic of new aircraft designs is dramatically increasing the complexity of both design and verification. Simultaneously, the multi-physics interactions between structural, electrical, thermal, and hydraulic components have become more significant as the systems become increasingly interconnected.

Hardware-in-the-loop (HIL) simulation in the development and test process of vehicle dynamics controllers requires a real-time tractor-trailer simulation model. The hitch coupling must be numerically stable to ensure real-time simulation for various driving maneuvers, particularly at the vehicle's handling limits. This paper presents a robust implementation of tractor-trailer coupling. The equation of motion is formed using a novel formulation which is a combination of Jourdain's Principle and the Articulated Body Algorithm. The paper shows that a robust model for a real-time tractor-trailer simulation can be achieved with the proposed method. Moreover, the approach presented is suitable for modular modeling, is successfully implemented and can also be used as a basis for flexible system definition with an adjustable number of trailer axles.

Hybrid test systems are gaining more and more significance in the aerospace industry. At the heart of these systems is a standardized communication infrastructure. There are many challenges when designing the communication infrastructure. For example, it requires very specific knowledge to boot a hybrid system, manage its configuration process, and start and stop the execution of applications, such as simulations, panels or recorders. Likewise, when testers use a heterogeneous test environment, they cannot commit themselves too much to every single test means and its special characteristics. Nevertheless, testers must always be able to monitor and control every test system. This means, they must be able to determine the current overall system status and the current status of its components and parts. Examples for this are hardware components, such as real-time processors and I/O boards, as well as software applications, such as real-time simulations models on the test system.

In recent years, the concept of hybrid test systems consisting of real and virtual parts emerged in the aerospace industry. The concept features a communication infrastructure that provides the standardized transport mechanisms required for interoperability. For example, this allows system integrators to easily reuse and exchange laboratory tests means, even if they originate from different suppliers. The “Virtual and Hybrid Testing Next Generation” (VHTNG) research project aims at creating a standard for such an infrastructure. One central aspect is the unified monitoring and control of the test equipment. So far, VHTNG has primarily focused on monitoring and controlling related aspects of the test bench in a local environment. However, recent events have repeatedly shown that it becomes increasingly important to monitor and control test benches remotely.

The current is an investigation of the effects of charge motion, namely tumble, on the burn characteristics of the new Chrysler Hemi SI engine. In order to reduce prototyping, several combustion system designs were evaluated; some of which were eliminated prior to design inception solely based on CFD simulations. The effects of piston top and number of spark plugs were studied throughout the conceptual stage with the AVL-FIRE CFD code. It has been concluded that large-scale, persistent and coherent tumbling flow structures are essential to charge motion augmentation at ignition only if such structures are decimated right before ignition. Piston top had a detrimental effect on tumbling charge motion as the piston approaches the TDC. When compared to single spark plug operation, dual spark plug reflected considerable improvement on burn characteristics and engine performance as a consequence. The CFD simulations demonstrated good correlation with early dynamometer data.

This paper presents a demonstrator developed in the European CleanSky2 project MISSION (Modelling and Simulation Tools for Systems Integration on Aircraft). Its scope is the development towards a seamless integrated, interconnected toolchain enabling more efficient processes with less rework time in todays, highly collaborative aerospace domain design applications. The demonstration described here, consists of an open, modular and multitool platform implementation, using specific techniques to achieve fully traceable (early stage) requirements verification by virtual testing. The most promising approach is a model based integration along the whole process from requirements definition to the verified, integrated (and certified) system. Extending previous publications in this series, the paper introduces the motivation and briefly describes the technical background and a potential implementation of a workflow suitable for that target.

This paper addresses the use of neat, indigenous biodiesel in advanced Mercedes-Benz passenger cars. Modern, unmodified EU3 Common-Rail diesel engines with second generation common rail technology were used to determine the effects of neat biodiesel on performance and emission characteristics. The biodiesel was made from the seeds of the Jatropha Curcas plant and sourced from the Central Salt and Marine Chemicals Research Institute in Bhavnagar, India. The production of biodiesel and the vehicle tests are part of a PPP project, funded jointly by the DaimlerChrysler AG and the German DEG. The project aims at providing additional jobs and income in rural Indian areas along with reclaiming unused wasteland. The test vehicles were operated for a cumulative 8000 kilometers with an intention to expose the vehicle and fuel to diverse climatic conditions.

The paper describes results from investigating Common Rail (CR) injection in a dedicated optical engine with optimum access to the whole cross section of the engine cylinder through piston. This engine maintains all production-type details of the combustion chamber geometry being crucial to the flow fields required for optimum engine performance. This optical engine is used along with 2D optical diagnostics for temperature, soot and OH as well as spray shadowgraphy to analyze all phases of injection and combustion under virtually real engine conditions. By using special prototype CR injectors, the effects of engine design and operation strategies on ignition, combustion and pollutant formation are studied and controlling parameters are isolated. Special emphasis is devoted to the effects of injector stability, spray symmetry, nozzle geometry, injection rate, pilot injection and swirl effects.