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A new six-speed transaxle has been introduced by the Chrysler Group of DaimlerChrysler AG. Along with the six forward ratios in the normal upshift sequence, this transaxle features a seventh forward ratio used primarily in a specific downshift sequence. A significant technical challenge in this design was the control of so-called double-swap shifts, the exchange of two shift elements for two other shift elements. In the case at hand, one of the elements is a freewheel. A unique solution is discussed for successful control of double-swap shifts. The new design replaces a four-speed transaxle but makes use of a large percentage of parts and processes from the four-speed design. This approach enabled the new transaxle to reach production in three years from concept. The new transaxle, referred to as the 62TE, has substantially improved performance and passing maneuvers coupled with a new 4.0L high output engine for which the 62TE was developed.

High demands in fuel consumption, efficiency, and low emissions lead to complex control functions for current and future diesel engine management systems. Great effort is necessary for their optimal calibration. At the same time, and particularly for cost reasons, many variants exist on one individual type of diesel engine management system. Not only is it used for several base engines, but these engines are also used in different environments and for different tasks. For optimal deployment, their calibration status must also be optimized individually. Furthermore, the demand for shorter development cycles and enhanced quality lead to a catalogue of new requirements for the calibration process and the affiliated tool. A new calibration system was developed, which optimally reflects the new demands.

Due to the rapidly increasing number of electronic control units (ECUs) in modern vehicles, software and ECU testing plays a major role within the development of automotive electronics. To ensure effective as well as efficient testing within the whole development process, a seamless transition in terms of the reusability of tests and test data as well as powerful and efficient means for developing and describing tests are required. This paper therefore presents a new integration approach for modern test development and test management. Besides a very easy-to-use way of describing tests graphically, the main focus of the new approach is on the management of a large number of tests, test data, and test results, allowing close integration into the automotive development processes.

We are the first to report about a micromachined flow sensor directly integrated in the Common Rail injection nozzle body between the double guidance and the tip of the nozzle. The thermal measurement principle is chosen, because it enables a very precise and fast detection of gaseous and liquid mass flows. Additionally, the velocity field in the nozzle is only slightly influenced by the integration of the sensor in the nozzle body due to the negligible height of the sensitive layer. For a hot film anemometer, a high pressure stable ceramic substrate can be used, fabricated in a low cost batch process. The technology, to fabricate the sensor, as well as the first flow measurements, carried out at a high pressure test set up, are presented.

A simple strategy for building lightweight automobile body-in-whites (BIWs) is developed and discussed herein. Because cost is a critical factor, expensive advanced materials, such as carbon fiber composites and magnesium, must only be used where they will be most effective. Constitutive laws for mass savings under various loading conditions indicate that these materials afford greater opportunity for mass saving when used in bending, buckling or torsion than in tensile, shear or compression. Consequently, it is recommended that these advanced materials be used in BIW components subject to bending and torsion such as rails, sills, “A-B-C” pillars, etc. Furthermore, BIW components primarily subject to tension, compression, or shear, such as floor pans, roofs, shock towers, etc., should be made from lower cost steel. Recommendations for future research that are consistent with this strategy are included.

Automotive technology is rapidly changing with electrification of vehicles, driver assistance systems, advanced safety systems etc. This advancement in technology is making the task of validation and verification of embedded software complex and challenging. In addition to the component testing, integration testing imposes even tougher requirements for software testing. To meet these challenges dSPACE is continuously evolving the Hardware-In-the-Loop (HIL) technology to provide a systematic way to manage this task. The paper presents developments in the HIL hardware technology with latest quad-core processors, FPGA based I/O technology and communication bus systems such as Flexray. Also presented are developments of the software components such as advanced user interfaces, GPS information integration, real-time testing and simulation models. This paper provides a real-world example of implication of integration testing on HIL environment for Chassis Controls.

The technological development in the field of automotive electronics is proceeding at almost break-neck speed. The functions being developed and integrated into cars are growing in complexity and volume. With the increasing number and variety of sensors and actuators, electronics have to handle a greater amount of data, and the acquisition and generation of I/O signals is also growing in complexity, for example, in engine management applications. Moreover, intelligent and complex algorithms need to be processed in a minimum of time. This all intensifies the need for Rapid Control Prototyping (RCP), a proven method of decisively speeding up the model-based software development process of automotive electronic control units (ECUs) [1],[2]. All these demanding tasks, including connecting sensors and actuators to the RCP system, need to be performed within a standard prototyping environment.

The development of perception functions for tomorrow’s automated vehicles is driven by enormous amounts of data: often exceeding a gigabyte per second and reaching into the terabytes per hour. Data is typically gathered by a fleet of dozens of mule vehicles which multiply the data generated into the hundreds of petabytes per year. Traditional methods for fueling data-driven development would record every bit of every second of a data logging drive on solid-state drives located on a PC in the vehicle. Recorded data must then be exported from these drives using an upload station which pushes to the data lake after arriving back at the garage. This paper considers different techniques for curating logged data.

In modern DI Diesel engines the raw emissions of NOx and soot are affected, apart from the fuel injection rate, by atomization of the liquid jet and mixing of the fuel with the combustion air. Thereby details of the fuel flow inside the injection nozzle play an essential role. In order to determine the general mechanisms and the effect of individual nozzle configuration parameters on the fuel atomization and the fuel spray propagation, methods for optical diagnostics and CFD have been developed at the DaimlerChrysler Research. These methods are combined with an analysis of the injection system hydraulics and linked to a detailed analysis of mixture formation and combustion inside an optically accessible engine. The first part of the paper methods for the experimental investigation with transparent 1- and 6- hole nozzles in real size geometries under high pressure conditions are described. Special emphasis is put on CFD methods for modeling the cavitating two phase nozzle flow.

Model-based software development and automatic code generation have become increasingly established in recent years. The automotive industry has widely adopted and successfully deployed these methods in many different series production programs worldwide. This brought various benefits, such as a reduction in development times, improved quality due to more precise specifications, and early verification and validation by means of simulation. At the same time, more and more safety-related and safety-critical systems have been - and will be -introduced into modern vehicles. Common examples are active front steering, adaptive cruise-control, and integrated chassis control. This leads to the question, if and how model-based design and automatic production code generation can be applied to the development of safety-critical systems.

This paper describes a new production code generator that meets both the requirements of code developers for efficient and reliable production code, as well as the desire of system engineers to establish a control design process based on simulation models that double as executable specifications for the ECU software. The production code generator supports automatic scaling, generates optimized fixed-point C code for microcontrollers like the Motorola 683xx, Siemens C16x, and Hitachi SH-2, and produces ASAP2 [1] calibration information. Benchmark results show that the autogenerated code can match or even exceed the efficiency of typical handwritten production code. Code quality is assured by design and by systematic, automatic, and extremely comprehensive test procedures.

This paper will first introduce and classify the basic principles of architecture-driven software development and will briefly sketch the presumed development process. This background information is then used to explain extensions which enable current behavior modeling and code generation tools to operate as software component generators. The generation of AUTOSAR software components using dSPACE's production code generator TargetLink is described as an example.

The following document offers insight into the work of the MOST Cooperation. Now that MOST is on the road, a short overview of five years of successful collaborative work of the partners involved and the results achieved will be given. Emphasis is put on the importance of a shared vision in combination with shared values as a prerequisite for targeted collaborative work. It is also about additional key success factors that led to the success of the MOST Cooperation. Your attention will be directed to the way the MOST Cooperation sets and achieves its goals. And you will learn about how the organization was set-up to support a fast progression towards the common goal. The document concludes with examples of recent work as well as an outlook on future work.

Function models have a well-established position in automotive software development. Formal system models, on the other hand, are rare. This article describes the various aspects of function and system models, focusing mainly on AUTOSAR-compatible models. It also depicts the challenges for future overall models that combine the function models and the system model, and the resulting benefits, such as early system verification via PC-based simulations.

The application of a communication infrastructure for hybrid test systems is currently a topic in the aerospace industry, as also in other industries. One main reason is flexibility. Future laboratory tests means (LTMs) need to be easier to exchange and reuse than they are today. They may originate from different suppliers and parts of them may need to fulfill special requirements and thus be based on dedicated technologies. The desired exchangeability needs to be achieved although suppliers employ different technologies with regard to specific needs. To achieve interoperability, a standardized transport mechanism between test systems is required. Designing such a mechanism poses a challenge as there are several different types of data that have to be exchanged. Simulation data is a prominent example. It has to be handled differently than control data, for example. No one technique or technology fits perfectly for all types of data.

In open jet wind tunnels with high blockage ratios a sharp rise in drag is observed for models approaching the nozzle exit plane. The physical background for this rise in drag will be analyzed in the paper. Starting with a basic analysis of the dependencies of the effect on model and wind tunnel properties, the key parameters of the problem will be identified. It will be shown using a momentum balance and potential flow theory that interaction between model and nozzle exit can result in significant tunnel-induced gradients at the model position. In a second step, a CFD-based investigation is used to show the interaction between nozzle exit and a bluff body. The results cover the whole range between open jet and closed wall test section interaction. The model starts at a large distance from the nozzle, then moves towards the nozzle, enters the nozzle and is finally completely inside the nozzle.

Hardware-in-the-loop (HIL) testing is indispensable in the software development process for control units and has been an integral part of the software development process for years. Large HIL systems for integration tests are used to test the correct behavior of distributed functions and the communication between the control units. The vast development programs that are involved require building duplicates of such test systems or parts of them, due to the fact that the tasks are distributed between different companies or different departments within a company. However, there is an alternative to duplicating a test system. Instead of using a cloned system, coupling HIL systems over large distances is an alternate approach. This paper presents what requirements this coupling must fulfill and and describes a path-breaking method to fulfill them. In addition, results of an implementation are shown.

The importance of electronics, especially software, has greatly increased over the last few years. Efforts to maintain a high level of software quality have made testing an important part of the development process. With the advent of model-based development, testing methods can be used not only on code level, but also on model level. Next to test execution itself, test development is seen as the most time- and cost-intensive part of the testing process. This paper outlines and classifies current approaches to model-based test development, with the aim of providing guidelines for test developers for choosing the method best suited to the type of system under test and the test objective.

The background for the development activities of the motor vehicle industry is strongly influenced by lawmakers, with engine development, in particular, coming under increasing pressure from the requirements of emissions legislation. Demands for CO2 reduction and thus corresponding savings in consumption contrast with regulations which call for compliance with extremely low emission levels, featuring the extreme of zero tailpipe emissions, and alternative low emission levels which make accurate measurement a problem even with current analysis technology. An example of such requirements are the SULEV limits of California law. These standards have given rise to a wide variety of emission control concepts, each of which, however, has certain limitations in its application. In the context of this general setting, the paper shows that the phase directly subsequent to cold start should be focused upon if these ambitious targets are to be reached.

This paper introduces the new 1.6L engine family, designed and developed by the Chrysler group of DaimlerChrysler Corporation in cooperation with BMW. An overview of the engine's design features is provided, with a detailed review of the performance development process with emphasis on airflow, combustion, thermal management and friction. This information is presented, to provide an understanding of how the engine simultaneously achieves outstanding levels of torque, power, fuel consumption, emissions and idle stability. The use of analytical tools such as Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) in the optimization of the engine is shown.