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The foremost aim of the work presented in this paper is to improve fuel economy and decrease CO2 emissions by reducing the aerodynamic drag of passenger vehicles. In vehicle development, computer aided engineering (CAE) methods have become a development driver tool rather than a design assessment tool. Exploring and developing the capabilities of current CAE tools is therefore of great importance. An efficient method for vehicle shape optimization has been developed using recent years' advancements in neural networks and evolutionary optimization. The proposed method requires the definition of design variables as the only manual work. The optimization is performed on a solver approximation instead of the real solver, which considerably reduces computation time. A database is generated from simulations of sampled configurations within the pre-defined design space. The database is used to train an artificial neural network which acts as an approximation to the simulations.

This paper presents measurements on Vehicle to Vehicle (V2V) communication between participants in a platooning application. Platooning, according to the SARTRE concept, implies several vehicles travelling together in tight formation, with a manually driven heavy lead vehicle. The platoon being studied consists of five vehicles; two trucks in the lead and three passenger cars. The V2V-communication node in each vehicle contains an 802.11p radio at 5,9 GHz. It is used to send messages between vehicles to coordinate movements and maintain safety in the platoon. Another cooperative application that relies on V2V-communication is multiple UAVs flying in formation; as investigated in KARYON. This project also investigates cooperative autonomous vehicles. In both applications, V2V-communication is an enabling technology. Two metrics are studied to quantify the V2V-communication quality: system packet error rate and consecutive packet loss.

A structured, semi-automatic method for reducing a high-fidelity engine model to a fast running one has been developed. The principle of this method rests on the fact that, under certain assumptions, the computationally expensive components of the simulation can be substituted with simpler ones. Thus, the computation speed increases substantially while the physical representation of the engine is retained to a large extent. The resulting model is not only suitable for fast running simulations, but also usable and updatable in later stages of the development process. The thrust of the method is that the calibration of the fast running components is achieved by use of automatically selected neural networks. Two illustrative examples demonstrate the methodology. The results show that the methodology achieves substantial increase in computation speed and satisfactory accuracy.

Normally, once a vehicle leaves production, newly manufactured spare parts are produced and bought to cover up to 15 years of use. An innovative concept is to view the fleet as a potential spare-parts store. On 1 August 1999 ECRIS AB launched a combined business and environmental project lasting 24 months on “Re-Use of Car Components From The Car Recycling Industry”. The target of the project is to develop and demonstrate a method and the business potential in re-using components from the recycling industry that today are sent for material recycling or depositing in landfills. Increased usage of components from ELV's is a sign of both customer and environmental care.

This article describes an expert system for objective rating of subjective characteristics like driving comfort. The system uses radial basis neural networks that can be trained on any dynamic properties, for example acceleration. Training and retraining can be done in real-time. The system includes a measure of the reliability of automatic judgement, which can be used to signal when new training may be necessary. The article shows in detail how the system has been used to automatically judge gearshift comfort for automatic transmission. Tests indicate that the system's accuracy and consistency are as good as one of Volvo's best experts.

OBD II established a new level for automotive on board diagnostics. This concept, state of the art, is already introduced on the market, MY-94, ( reference 1). We will now go one step further by introducing the Diagnose 2 Concept. With D2 we connect almost all ECU's in a vehicle to the same diagnostic communication bus, connected to the same pin, (pin 7 in the J1962 connector). It will now be possible to hook up to all ECU's with one connector, the OBD II connector inside the passenger compartment, (this will not be any problem for a properly programmed OBD II Scan Tool, as it only will look for the emission related ECU's).