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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.

In the present study, the exterior air flow over convertibles together with the interior flow in the passenger compartment has been calculated using the commercial CFD program STAR-CD. The investigations have been performed for a SLK-class Mercedes with two occupants. The computational mesh consists of about 3 million hexahedra cells. The detailed informations of the calculated flow field have been used to elaborate the characteristic flow phenomena and increase the physical understanding of the flow. The influence of different geometrical modifications (variations of roof spoiler, variations of the draft stop behind the seats etc.) on the flow field and the air draft experienced by the occupants has been analyzed. To proof the accuracy of the numerical results, wind tunnel experiments in a full scale and 1:5 scale wind tunnel have been carried out for the basic car model as well as for several geometrical variations.

A look at the various past achievements in the field of passenger car safety raises the question whether any dramatic steps towards its improvement can still be expected. Will progress be confined to the optimization of existing systems or does the future hold new substantial safety steps? This paper elaborates on the issue that the time available before a potential accident occurs can be used to improve the safety of occupants and other involved road users. Accident analysis confirms that this is feasible for about two-thirds of all accidents. The recognition of an imminent collision bears a noteworthy potential for accident prevention, reduction of accident severity and injury severity. The former boundary between active and passive safety thus fades continually. Based upon this it is possible to describe vehicle safety by a comprehensive approach encompassing seven escalation levels.

In the present study, the thermal comfort in a convertible has been evaluated using the in-house program TEKOS. The investigations have been performed for a SLK-class Mercedes with two occupants. The computational mesh consists of about 3 million hexahedra cells. TEKOS has been adapted to open driving conditions. The influence of the air-conditioning system and of different draft stops on the thermal comfort has been investigated in an autumn case. The study has shown, that in a basic case without draft stop and air conditioning the evaluation results in very poor thermal comfort values at the whole body, especially at unclothed parts of the body. If a draft stop and maximum heating is regarded, almost all parts of the body are close to the comfort range except of the head region. With TEKOS it is possible to quantify the influence of different parameters on the thermal sensation in convertibles with the advantage of an objective thermal evaluation.

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.

Suspension systems have a major effect on the handling characteristics of a vehicle, particularly ride comfort and handling safety, and thus substantially determine its character. Their increasing significance is reflected by the greater value that ever more demanding customers attribute to the properties ride comfort and handling safety. Now that the potential of conventional, passive systems is largely exhausted, adaptive and active systems open up new possibilities, e.g.: the suppression of rolling and pitching movements, handling and ride height independent of load, handling characteristics and ride height adaptable to situation and customer requirement. The DaimlerChrysler active suspension and damping system (Active Body Control – ABC) manages to resolve the conflict of aims between handling safety and ride comfort which afflicts conventional fixed suspension systems, and as a result offers greater freedom of layout whilst enabling optimization of both target criteria.

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.

In the automotive industry, the model-based approach is increasingly establishing itself as a standard paradigm for developing control unit software. Just as code reviews are widespread in classical software development as a quality assurance measure, models also have to undergo a stringent review procedure – particularly if they serve as a starting point for automatic implementation by code generators. In addition to these model reviews, the generated production code is reviewed later in the development process by performing auto code reviews. This article will present procedures for and give an account of experiences with model and code reviews which have been adapted to the model-based development process.

One of the world's most noble and high quality automobile brands is being revived: Maybach Aestetics, poise, perfection and technical brilliance founded the reputation of the magnificient Maybach sedans and convertibles, whose “Zeppelin” flagship, with a length of around 5.50 metres, was once the most prestigious German passenger car on the road - “an automobile which fulfills every last desire with refined elegance and power”, as the luxury automobile brand's brochure stated in 1934. DaimlerChrysler now feels obliged to live up to these high standards. As cornerstones of this vehicle concept, focus was placed on the topics of design, comfort, spatial availability, safety, exclusiveness and extra-ordinary performance. A major role was given to the powertrain in order to meet outstanding driving comfort and agility.

In the present paper, first results of an extensive and ongoing parametric study are shown. The objective of the parametric study is to clarify the influence of relevant flow and geometrical parameters on the microclimate and thermal comfort of the occupants. Flow parameters included in the study are air mass fluxes, velocity magnitude, air temperature and inflow direction at the vents. Geometrical parameters of interest are number, location, area and shape of the air vents as well as geometrical details of the passenger compartment itself. The parametric study is performed numerically on the basis of a computational model for a passenger compartment of a Mercedes E-Class sedan. The numerical method used has been published earlier and consists of a system of three programs for simulating the flow and temperature field in the cabin, the heat transfer and radiation and the thermal sensation of the occupants.

The development of electronic intelligence and the continually increasing intensive knowledge of driving dynamics make it possible nowadays to conceive intelligent vehicle systems and to make such systems available for series production, which are capable of substantially enhancing the active safety of commercial vehicles. Through the implementation of advanced subsystems, which can be integrated as software packages into the basic electronic braking system, it will be possible to expand the possibilities of introducing assistance systems, which are capable of both, helping and relieving the driver from stress in critical situations. The driver will be relieved of all duties which could divert his attention or cause severe stress. As a consequence, the active safety of commercial vehicles will be considerably increased.

The complexity of electrical/electronic vehicle systems mandates a systematic approach to the development of vehicle control, infotainment or comfort functions as well as the integration of these functions in an in-vehicle network consisting of several dedicated bus systems and according gateways. Due to reduced time-to-market, the integration has to be performed in a virtual environment. The classical Digital Mockup (DMU) addresses the physical integration of EE systems as mechanical components. However, functional aspects play a dominant role in EE vehicle systems. For this reason, functional integration defines a multi-view, mixed-level approach to the description, transformation, verification and integration of vehicle functions under consideration of the physical vehicle integration.

This paper evaluates several durability tire models using Virtual Tire Testing (VTT) strategy. VTT conducts tire testing (simulation) using LS–DYNA based on a Virtual Tire which is built by 3–D finite element mesh. VTT is repeatable and could do special tire tests which can't be done using normal tire testing bench. A brief review is given on durability tire models and several typical tire models are selected for this study. All the necessary parameters for establishing the analytical tire models are extracted from the Virtual Tire. Quarter vehicle model is used to simulate the vehicle vertical vibration. The comments of those analytical tire models are given based on their performance vs. VTT.