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Many software functions currently available in the engine control units have been developed for several years (decades in some cases), reengineered or adapted due to new requirements, what may add to their inherent complexity an unnecessary complication. This paper deals with the study and implementation of a software reengineering strategy for the embedded domain, which is in transfer from research department to product development, here applied to improve maintainability of flex fuel functions. The strategy uses the SCODE “Essential Analysis”, an approach for the embedded system domain. The method allows to reduce the system complexity to the unavoidable inherent problem complexity, by decomposing the system into smaller sub problems based on its essential physics. A case study was carried out to redesign a function of fuel adaptation. The analysis was performed with the support of a tool, which covers all the phases of the method.

Based on the results of “An Evaluation of the Mechanical Properties of Wheel Force Sensors and their Impact on to the Data Collected During Different Driving Manoeuvres” Herrmann et al. (SAE Paper 05M-254) a second, detailed investigation has been started to acquire additional information. In this previous investigation, it has been found out, that a difference in mass can be clearly identified in the signals. The current paper summarizes the results of a detailed investigation, which has been performed at DaimlerChrysler Stress Lab in Auburn Hills, with a fully equipped vehicle - a set of 2/4 Wheel Force Sensors plus several acceleration sensors as well. Through careful research and testing it is expected that the differences in the dynamic behavior can be specified with better accuracy than in the previous study.

Six-component wheel force sensor (WFS) systems have become an important tool for many different applications in vehicle development - particularly for road load data acquisition and road simulation in durability engineering. All known measuring wheel concepts integrate single or multiple sensors into a modified rim. It is obvious, that this modification leads to a more or less severe change of important mechanical properties compared to a standard aluminium or steel rim. The following paper will summarize the results of a comprehensive investigation of the influence of different mechanical properties and their impact on test data. The basis of this research will be a set of standard analyses and experiments, e.g. determination of natural frequencies, stiffness and mass/inertia performed with standard aluminium and steel rims as well as a typical light-weight measuring wheel with and without tyre.

The development of future automotive electronic systems requires new concepts in the software architecture, development methodology and information exchange. At Bosch an XML and MSR based technology is applied to achieve a consistent information handling throughout the entire software development process. This approach enables the tool independent exchange of information and documentation between the involved development partners. This paper presents the software architecture, the specification of software components in XML, the process steps, an example and an exchange scenario with an external development partner.

In recent years wheel dynamometer measuring systems,using strain gauge and quartz technologies, have been optimised and are mature now. For specific fields of application the use of sensors based on either of the two measuring technologies would be the technically optimal choice. For technical, practical and economic reasons often two systems in parallel couldn't be used and thus limitations needed to be accepted. In order to overcome these limitations Kistler integrated sensors with both measurement technologies into one product family. Using results from practical applications and investigations the paper describes the new potential to get better test results faster. Kistler continously works towards a better integration of engineering processes (numerical simulation, testing on benches and in the vehicle).

This paper reports on test bed and field studies to adapt and optimise two John Deere tractor engines for fatty acid methyl ester (biodiesel). Emissions were measured according to the international standard DIN EN ISO 8178-4, cycle C1, which is relevant for tractor engines. The results were compared to diesel fuel with and without optimisation of the engine for biodiesel. It could be shown that total particulate emissions did not change much with biodiesel but there was a strong increase in the soluble organic fraction while soot strongly decreased simultaneously. So in order to take full advantage of biodiesel the engines were also equipped with an oxidation catalyst. Compared to diesel fuel operation of the engines with oxidation catalyst, the emissions of hydrocarbons, carbon monoxide and particulates could be reduced with biodiesel whereas nitrogen oxides increased slightly.

In the past decades car structures have been optimized for the most frequent accident, the frontal impact. Together with the restraint systems (safety belt, airbag) they provide good protection for the front passengers in this type of collision. Due to this fact the side impact must now get relatively more importance. Today, more than one third of seriously injured occupants are the consequences of vehicle side collisions. In order to test and classify vehicle safety in side collisions, different test procedures have been proposed. The basic assumption of these test procedures is that the striking car can be replaced by a moveable barrier. A comparative study of side impacts with moving rigid and deformable barriers has been performed by means of the finite element technique.