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A large number of testing procedures have been developed to ensure vehicle safety in common and extreme driving situations. However, these conventional testing procedures are insufficient for testing autonomous vehicles. They have to handle unexpected scenarios with the same or less risk a human driver would take. Currently, safety related systems are not adequately tested, e.g. in collision avoidance scenarios with pedestrians. Examples are the change of pedestrian behaviour caused by interaction, environmental influences and personal aspects, which cannot be tested in real environments. It is proposed to use augmented reality techniques. This method can be seen as a new (Augmented) Pedestrian in the Loop testing procedure.

To achieve global climate goals, greenhouse gas emissions must be drastically reduced. The energy and transportation sectors are responsible for about one third of the greenhouse gases emitted worldwide, and they often use internal combustion engines (ICE). One effective way to decarbonize ICEs may be to replace carbon-containing fossil fuels such as natural gas entirely, or at least partially, with hydrogen. Cost-effective development of sustainable combustion concepts for hydrogen and natural gas/hydrogen mixtures in ICEs requires the intensive use of fast and robust simulation tools for prediction. The key challenge is appropriate modeling of flame front propagation. This paper evaluates and applies different approaches to modeling laminar flame speeds from the literature. Both appropriate models and reaction kinetic calculations are considered.

Virtual sensing, i.e., the method of estimating quantities of interest indirectly via measurements of other quantities, has received a lot of attention in various fields: Virtual sensors have successfully been deployed in intelligent building systems, the process industry, water quality control, and combustion process monitoring. In most of these scenarios, measuring the quantities of interest is either impossible or difficult, or requires extensive modifications of the equipment under consideration – which in turn is associated with additional costs. At the same time, comprehensive data about equipment operation is collected by ever increasing deployment of inexpensive sensors that measure easily accessible quantities. Using this data to infer values of quantities which themselves are impossible to measure – i.e., virtual sensing – enables monitoring and control applications that would not be possible otherwise.

Hybrid electric vehicles (HEVs) with a power-split system offer a variety of possibilities in reduction of CO2 emissions and fuel consumption. Power-split systems use a planetary gear sets to create a strong mechanical coupling between the internal combustion engine, the generator and the electric motor. This concept offers rather low oscillations and therefore passive damping components are not needed. Nevertheless, during acceleration or because of external disturbances, oscillations which are mostly influenced by the ICE, can still occur which leads to a drivability and performance downgrade. This paper proposes a design of an active damping control system which uses the electric motor to suppress those oscillations instead of handling them within the ICE control unit. The control algorithm is implemented as part of an existing hybrid controller without any additional hardware introduced.

The pedestrian model in PC-Crash is based on a multi-body system, where several bodies are interconnected by joints. Each of these bodies can have different properties to represent the different parts of the human body. The joint properties can be specified independently as well. The theoretical background of the pedestrian model has been introduced in SAE 1999-01-0445 and the model shows to give a good correlation of the gross movement of the pedestrian compared to crash test data. As there are many parameters, which can and have to be specified for the pedestrian model as input parameters, an in depth validation of the different parameters has to be done to validate this model. This paper describes in detail the validation process for the pedestrian model. A significant number of crash tests (approx. 30) was used as a basis to compare the results of the simulations and the real movement of the test subjects.

Trim materials are often used for vibroacoustic energy absorption purposes within vehicles. To estimate the sound impact at a driver’s ear, the substructuring approach can be applied. Thus, transfer functions are calculated starting from the acoustic source to the car body, from the car body to the trim and, finally, from the trim to the inner cavity where the driver is located. One of the most challenging parts is the calculation of the transfer functions from the car body inner surface to the bottom trim surface. Commonly, freely laying mass-spring systems (trims) are simulated with a fixed boundary and interface phenomena such as friction, stick-slip or discontinuities are not taken into consideration. Such an approach allows for faster simulations but results in simulations strongly overestimating the energy transfer, particularly in the frequency range where the mass-spring system’s resonances take place.

The development of future internal combustion engines and fuels is influenced by decreasing energy resources, restriction of emission legislation and increasing environmental awareness of humanity itself. Alternative renewable fuels have, in dependency on their physical and chemical properties, on the production process and on the raw material, the potential to contribute a better well-to-wheel-CO2-emission-balance in automotive and nonautomotive applications. The focus of this research is the usage of alcohol fuels, like ethanol and 2-butanol, in motorcycle high power engines. The different propulsion systems and operation scenarios of motorcycle applications in comparison to automobile applications raise the need for specific research in this area.

Millions of small displacement single-cylinder engines are used for the propulsion of scooters, motorcycles, small boats and others. These SI-engines represent the basis of an affordable mobility in many countries, but at the same time their efficiency is quite low. Today, the limited fossil fuel resources and the anthropogenic climate require a sustainable development of combustion engines, the reduction of fuel consumption being an important factor. A variety of different strategies (turbo-charging, cylinder deactivation, direct injection, etc.) are investigated here to increase the efficiency of multi-cylinder engines. In the case of small displacement single-cylinder engines, other strategies are required because of their special design and the high pressure on costs. In the context of this paper different layout parameters which have an influence on the working process are investigated, with the aim of increasing the efficiency of small displacement single-cylinder engines.

A steady increasing share and complexity of automotive software is a huge challenge for quality management during software development and in-use phases. In cases of faults occurring in customer’s use, warranty leads to product recalls which are typically associated with high costs. To avoid software faults efficiently, quality management and enhanced development processes have to be realized by the introduction of specific analysis methods and Key Process/Performance Indicators (KPIs) to enable objective quality evaluations as soon as possible during product development process. The paper introduces an application of specific analysis methods by using KPIs and discusses their potential for automotive software quality improvement. Target is to support quality evaluation and risk-analysis for the release process of automotive software.

Focus is pointed on the highly favorable physical properties of hydrogen (H2) with regard to its combustion characteristics in internal combustion engines. Thereby it will be shown in how far the performance of next generation hydrogen engines can be improved by implementing a direct fuel injection system instead of the conventional port injection approach. Results from numerical as well as from experimental investigations will be used to clearly give a vision of the overall future potential of hydrogen for combustion engines in comparison to fuel cell systems.

The paper focuses on an optimization methodology, which uses Design of Experiments (DoE) methods to define component parameters of parallel hybrid powertrains such as number of gears, transmission spread, gear ratios, progression factor, electric motor power, electric motor nominal speed, battery voltage and cell capacity. Target is to find the optimal configuration based on specific customer targets (e.g. fuel consumption, performance targets). In the method developed here, the hybrid drive train configuration and the combustion engine are considered as fixed components. The introduced methodology is able to reduce development time and to increase output quality of the early system definition phase. The output parameters are used as a first hint for subsequently performed detailed component development. The methodology integrates existing software tools like AVL CRUISE [5] and AVL CAMEO [1].

This paper describes the development of a 0-D-sulfur poisoning model for a NOx storage catalyst (NSC). The model was developed and calibrated using findings and data obtained from a passenger car diesel engine used on testbed. Based on an empirical approach, the developed model is able to predict not only the lower sulfur adsorption with increasing temperature and therefore the higher SOx (SO2 and SO3) slip after NSC, but also the sulfur saturation with increasing sulfur loading, resulting in a decrease of the sulfur adsorption rate with ongoing sulfation. Furthermore, the 0-D sulfur poisoning model was integrated into an existing 1-D NOx storage catalyst kinetic model. The combination of the two models results in an “EAS Model” (exhaust aftertreatment system) able to predict the deterioration of NOx-storage in a NSC with increasing sulfation level, exhibiting higher NOx-emissions after the NSC once it is poisoned.

Advanced Driver Assistance Systems (ADAS) for collision avoidance/mitigation have already demonstrated their benefit on vehicle safety. Often those systems have an additional functionality for comfort to assist the driver in non-critical driving. The verification of ADAS functionality using different test scenarios is currently investigated in many different projects worldwide. A harmonization of test scenarios and evaluation criteria is not yet accomplished. Often, these test scenarios focus on objective collision avoidance and not on the subjective interaction between driver and vehicle. The present study deals with the development of an experimental validation plan for the systems Automatic Cruise Control (ACC), Lane Departure Warning (LDW) and Lane Keeping Assist (LKA). Standardized driving maneuvers with two or more vehicles equipped with synchronized measurement are performed by professional test drivers.

Looking at upcoming emission legislations for two-wheelers, it is quite obvious that the fulfilment of these targets will become one of the biggest challenges within the engine development process. The gradual harmonization of emission limits for two-wheelers with existing automotive standards will subsequently lead to new approaches regarding mixture preparation and exhaust gas aftertreatment. Referring to these future scenarios, a state-of-the-art in development of catalytic converters for two- or three-wheeler applications should be presented. After choosing a suitable test carrier, which has already been equipped with EFI components including an oxygen sensor for λ=1 operation mode, a basic injection system calibration was used to optimize the combustion process. Based on this setup, a variable exhaust system was manufactured to be able to integrate different catalyst configurations.

Discussions about the optimal technology of propulsion systems for future ground vehicles have been raising over the last few years. Several options include different types of technologies. However, those who are advocating conventional internal combustion engines are faced with the fact that fossil fuels are limited. Others favor hydrogen fuel as the solution for the future, either in combination with combustion engines or as an energy carrier for fuel cells. In any case, the production and storage of hydrogen is an ongoing challenge of numerous research works. Finally, there are battery-electric or hybrid propulsion systems in use, gaining more and more popularity worldwide. Ongoing advances in power electronics help to improve control systems within automotive applications. New developed or designed components enable more efficient system architectures and control.

It is critical for gas and dual fuel engines to have improved transient characteristics in order that they can successfully compete with diesel engines. Testing of transient behavior as well as of different control strategies for the multi-cylinder engine (MCE) should already be done on the single cylinder engine (SCE) test bed during the development process. This paper presents tools and algorithms that simulate transient MCE behavior on a SCE test bed. A methodology that includes both simulation and measurements is developed for a large two-stage turbocharged gas engine. Simple and fast models and algorithms are created that are able to provide the boundary conditions (e.g., boost pressure and exhaust back pressure) of a multi-cylinder engine in transient operation in real-time for use on the SCE test bed. The main models of the methodology are discussed in detail.

Automated, conductive charging systems enable both, the transmission of high charging power for long electric driving distances as well as comfortable and safe charging processes. Especially by the use of heavy and unhandy cables for fast charging, these systems offer user friendly vehicle charging - in particularly in combination with autonomously driving and parking vehicles. This paper deals with the definition of requirements for automated conductive charging stations with standard charging connectors and vehicle inlets and the development of a fully-automated charging robot for electric and plug-in hybrid vehicles. In cooperation with the project partners BMW AG, MAGNA Steyr Engineering, KEBA AG and the Institute of Automotive Engineering at Graz University of Technology, the development and implementation of the prototype took place in the course of a governmental funded research project titled “Comfortable Mobility by Technology Integration (KoMoT)”.

The reduction of environmentally harmful gases and the ambitions to reduce the exploitation of fossil resources lead to stricter legislation for all mobile sources. Legislative development significantly affected improvements in emissions and fuel consumptions over the last years, mainly measured under laboratory conditions. But real world operating scenarios have a major influence on emissions and it is already well known that these values considerably differ from officially published figures [1]. There are regulated emissions by the European Commission by means of real driving scenarios for passenger cars. A methodology to measure real drive emissions RDE is therefore well approved for automotive applications but was not adapted for two-wheeler-applications yet [2]. Hence measurements have been performed on-road and on chassis dynamometer for motorcycles with the state of the art RDE measurement equipment to be prepared for possible future legislation.

This paper introduces a research project on a spark ignition engine used in non-road applications. The aim is to illustrate the present situation as basis for comparison and to identify possible improvement potential in terms of performance, efficiency or exhaust and noise emissions. The study is carried out in two steps. First a standard walk-behind lawn mower is equipped with measuring instrumentation for recording the cutting forces and the engine variables during real world operation. The tests are carried out on three different lawn types and two different blade types are investigated. Consequently, in a second step the engine is analysed on the engine test bench in stationary and transient operating mode. A complete engine mapping is done regarding all relevant variables. Additionally to the outdoor tests, fuel consumption and engine out emissions are measured on the engine dynamometer. The recorded data enables a detailed analysis of the engine behaviour.

Precise three-dimensional dummy head trajectories during crash tests are very important for vehicle safety development. To determine precise trajectories with a standard deviation of approximately 5 millimeters, three-dimensional video analysis is an approved method. Therefore the tracked body is to be seen on at least two cameras during the whole crash term, which is often not given (e.g. head dips into the airbag). This non-continuity problem of video analysis is surmounted by numerical integration of differential un-interrupted electrical rotation and acceleration sensor signals mounted into the tracked body. Problems of this approach are unknown sensor calibration errors and unknown initial conditions, which result in trajectory deviations above 10 centimeters.