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With battery electric vehicles (BEV), due to the absence of the combustion process, the rolling noise comes even more into play. The BEV technology also leads to different concepts of how to mount the electric engine in the car. Commonly, also applied with the Audi e-tron, the rear engine is mounted on a subframe, which again is connected to the body structure. This concept leads to a better insulation in the high frequency range, yet it bears some problems in designing the mounts for ride comfort (up to 20Hz) or body boom (up to 70Hz). Commonly engine mounts are laid-out based on driving dynamics and driving comfort (up to 20Hz). The current paper presents a new method to find an optimal mount design (concerning the stiffness) in order to reduce the dynamic chassis forces which are transferred to the body (>20Hz). This directly comes along with a reduction of the sound pressure level for the ‘body boom’ phenomena.

During series production of modern combustion engines a major challenge is to ensure the correct operation of every engine part. A common method is to test engines in end-of-line (EOL) cold test stations, where the engines are not fired but tugged by an electric motor. In this work we present a physically based 0D model for dynamic simulation of combustion engines under EOL test conditions. Our goals are the analysis of manufacturing faults regarding their detectability and the enhancement of test procedures under varying environmental conditions. Physical experiments are prohibitive in production environments, and the simulative approach reduces them to a minimum. This model is the first known to the authors exploring advanced engine test methods under production conditions. The model supports a wide range of manufacturing faults (with adjustable magnitude) as well as error-free production spread in engine components.

Brake Particle Emission (BPE) is gaining considerable importance for the friction brake and automotive industry. So far no common approach or legislation for BPE characterization exists although many activities in this field have been started during the last years. Taking this into account, the authors carried out a joint measurement campaign to investigate a new approach regarding the sampling location using a brake dynamometer. During preliminary investigations the influence of the cooling air quality has been examined and a sampling point position validation has been carried out. At first the stabilization behavior for repeated test cycles and variations of volumetric air flow rates are analyzed. As a next step the role of volatile particle emissions is determined. Subsequently, the influence of load history and friction power is studied. Finally results in terms of the role of high temperature applications are presented.

Good lighting is crucial for safe driving at night. Unfortunately, many parameters are contributing to the final result of the individual tolerances of car body, dynamics and headlamp: the resulting aim. The paper will analyze individual tolerance contributors from car body parameters like load, tire pressure, suspension as well as temperature parameters of chassis and plastic parts. The investigation shows that the headlight aim can fluctuate in a worst case scenario more than ±0.3°.

Audi has developed a new compact V6 engine, with a displacement of 2.8 litres and an output of 128 kW (Fig. 1). The engine is extremely short, with an overall length of only 432 mm, and weighs just 161 kg (Fig. 2). The engine has been designed with two valves per cylinder, crossflow cylinder heads, overhead camshafts and hydraulic tappets (Fig. 3). These features, coupled with a newly developed variable geometry inlet manifold which changes the tuned length of the intake system according to the engine speed, have made it possible to produce an engine with an exceptionally high level of torque in the 2000-3500 rpm engine speed range.

Hybrid vehicle simulation methods combine physical test articles (vehicles, suspensions, etc.) with complementary virtual vehicle components and virtual road and driver inputs to simulate the actual vehicle operating environment. Using appropriate components, hybrid simulation offers the possibility to develop more accurate physical tests earlier, and at lower cost, than possible with conventional test methods. MTS Systems has developed Hybrid System Response Convergence (HSRC), a hybrid simulation method that can utilize existing durability test systems and detailed non-real-time virtual component models to create an accurate full-vehicle simulation test without requiring road load data acquisition. MTS Systems and Audi AG have recently completed a joint evaluation project for the HSRC hybrid simulation method using an MTS 329 road simulator at the Audi facility in Ingolstadt, Germany.

The use of a newly developed approach results in a highly accurate three dimensional analysis of the occupant movement. The central point of the new method is the calculation of precise body-trajectories by fitting standard sensor-measurements to video analysis data. With the new method the accuracy of the calculated trajectories is better than 5 to 10 millimeters. These body trajectories then form the basis for a new multi-body based numerical method, which allows the three dimensional reconstruction of the dummy kinematics. In addition, forces and moments acting on every single body are determined. In principle, the body movement is reconstructed by prescribing external forces and moments to every single body requiring that it follows the measured trajectory. The newly developed approach provides additional accurate information for the development engineers. For example the motion of dummy body parts not tracked by video analysis can be determined.

Diesel engines face difficult challenges with respect to engine-out emissions, efficiency and power density as the legal requirements concerning emissions and fuel consumption are constantly increasing. In general, for a diesel engine to achieve low raw emissions a well-mixed fuel-air mixture, burning at low combustion temperatures, is necessary. Highly premixed diesel combustion is a feasible way to reduce the smoke emissions to very low levels compared to conventional diesel combustion. In order to reach both, very low NOX and soot emissions, high rates of cooled EGR are necessary. With high rates of cooled EGR the NOX formation can be suppressed almost completely. This paper investigates to what extent the trade-off between emissions, fuel consumption and power of a diesel engine can be resolved by highly premixed and low temperature diesel combustion using injection nozzles with reduced injection hole diameters and high pressure fuel injection.

It is the beginning of a new age: multicore technology from the PC desktop market is now also hitting the automotive domain after several years of maturation. New microcontrollers with two or more main processing cores have been announced to provide the next step change in available computing power while keeping costs and power consumption at a reasonable level. These new multicore devices should not be confused with the specialized safety microcontrollers using two redundant cores to detect possible hardware failures which are already available. Nor should they be confused with the heterogeneous multicore solutions employing an additional support core to offload a single main processing core from real-time tasks (e.g. handling peripherals).

This paper shall give an idea of a lighting strategy a car company could have decided in an senior management circle. It is a medium to long term approach dealing with styling, design, innovation, quality and environmental aspects. Cost influences will be pointed out. It gives examples how different target conflicts could be handled and how or where to find mutual gain. Some “natural” conflicts between styling, engineering and marketing in car development are discussed. The different roles a car company could play in the development process will be shown. Is a car company responsible for the application of parts only or should it take the development leadership? And how could it be in future? Chances and risks will be pointed out.

At single irregularities, such as manhole covers and joints in concrete road surfaces, axle and engine vibrations are increased. Depending on the response characteristic of the vehicle chassis and seats and the duration of the event, such excitations can have a considerable influence on the comfort of vehicle occupants. With the objective of optimising the vibration characteristics of the axles of a vehicle, a procedure is presented which clarifies the motion sequences due to certain types of excitation on a roller test stand. This knowledge permits the optimisation of the axle kinematics, the axle bearings, and the spring-damper system.

The extended steady state lap time simulation combines a quasi steady state approach with a transient vehicle model. The transient states are treated as distance dependent parameters during the calculation of the optimal lap by the quasi steady state method. The quasi steady state result is used afterwards to calculate a new dynamic behavior, which induces in turn a different quasi steady state solution. This iteration between the two parts is repeated until the dynamic states have settled. An implementation of the extended quasi steady state simulation is built up to determine the capabilities of the approach. In addition to pure steady state simulation abilities, the method is able to judge the influence of the transient or time variant vehicle states on lap time. Sensitivity studies are generated to analyze the influence of basic parameters like mass, but also the influence of parameters with transient interaction like vertical damping or tire temperature.

Future applications in the automotive domain such as distributed control functions need a highly dependable communication system. The current FlexRay standard already provides high transmission speeds and addresses deterministic data communication. This paper shows how to enhance the safety properties for handling a new set of applications and speeding up the communication even more. The concept of Layered FlexRay is based on the FlexRay protocol and addresses the requirements of safety-relevant applications in a distributed communication network. An implementation of this approach is depicted with a Safety Core hardware chip. It is designed to handle the communication between the FlexRay system beneath and the application on the host CPU above, providing highly efficient data management and execution of safety functions which otherwise would have to be executed in software on the host CPU.

The current automotive electronic and electrical (EE) architecture has reached a scalability limit and in order to adapt to the new and upcoming requirements, novel automotive EE architectures are currently being investigated to support: a) an Ethernet backbone, b) consolidation of hardware capabilities leading to a centralized architecture from an existing distributed architecture, c) optimization of wiring to reduce cost, and d) adaptation of service-oriented software architectures. These requirements lead to the development of Zonal EE architectures as a possible solution that require appropriate adaptation of used security mechanisms and the corresponding utilized hardware trust anchors. 1 The current architecture approaches (ECU internal and in-vehicle networking) are being pushed to their limits, simultaneously, the current embedded security solutions also seem to reveal their limitations due to an increase in connectivity.

For the measurement of exhaust emissions, Constant Volume Sampling (CVS) technology is recommended by legislation and has proven its practical capability in the past. However, the introduction of new low emission standards has raised questions regarding the accuracy and variability of the CVS system when measuring very low emission levels. This paper will show that CVS has the potential to achieve sufficient precision for certification of SULEV concepts. Thus, there is no need for the introduction of new test methods involving high cost. An analysis of the CVS basic equations indicates the importance of the Dilution Factor (DF) for calculating true mass emissions. A test series will demonstrate that, by adjusting the dilution and using state of the art analyzers, the consistency of exhaust results is comparable with those of LEV concepts, measured with conventional CVS systems and former standard analyzers.