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The improvement of vehicle soiling behavior has increasing interest over the past few years not only to satisfy customer requirements and ensure a good visibility of the surrounding traffic but also for autonomous vehicles, for which soiling investigation and improvement are even more important due to the demands of the cleanliness and induced functionality of the corresponding sensors. The main task is the improvement of the soiling behavior, i.e., reduction or even prevention of soiling of specific surfaces, for example, windows, mirrors, and sensors. This is mostly done in late stages of vehicle development and performed by experiments, e.g., wind tunnel tests, which are supplemented by simulation at an early development stage. Among other sources, the foreign soiling on the side mirror and the side window depend on the droplet detaching from the side mirror housing.

The reduction of both harmful emissions (CO, HC, NOx, etc.) and gases responsible for greenhouse effects (especially CO2) are mandatory aspects to be considered in the development process of any kind of propulsion concept. Focusing on ICEs, the main development topics are today not only the reduction of harmful emissions, increase of thermodynamic efficiency, etc. but also the decarbonization of fuels which offers the highest potential for the reduction of CO2 emissions. Accordingly, the development of future ICEs will be closely linked to the development of CO2 neutral fuels (e.g. biofuels and e-fuels) as they will be part of a common development process. This implies an increase in development complexity, which needs the support of engine simulations. In this work, the virtual modeling of real fuel behavior is addressed to improve current simulation capabilities in studying how a specific composition can affect the engine performance.

This paper summarizes the development of a wireless message from infrastructure-to-vehicle (I2V) for safety applications based on Dedicated Short-Range Communications (DSRC) under a cooperative agreement between the Crash Avoidance Metrics Partners LLC (CAMP) and the Federal Highway Administration (FHWA). During the development of the Curve Speed Warning (CSW) and Reduced Speed Zone Warning with Lane Closure (RSZW/LC) safety applications [1], the Basic Information Message (BIM) was developed to wirelessly transmit infrastructure-centric information. The Traveler Information Message (TIM) structure, as described in the SAE J2735, provides a mechanism for the infrastructure to issue and display in-vehicle signage of various types of advisory and road sign information. This approach, though effective in communicating traffic advisories, is limited by the type of information that can be broadcast from infrastructures.

This paper summarizes the validation of prototype vehicle-to-infrastructure (V2I) safety applications based on Dedicated Short Range Communications (DSRC) in the United States under a cooperative agreement between the Crash Avoidance Metrics Partners LLC (CAMP) and the Federal Highway Administration (FHWA). After consideration of a number of V2I safety applications, Red Light Violation Warning (RLVW), Curve Speed Warning (CSW) and Reduced Speed Zone Warning with Lane Closure Warning (RSZW/LC) were developed, validated and demonstrated using seven different vehicles (six passenger vehicles and one Class 8 truck) leveraging DSRC-based messages from a Road Side Unit (RSU). The developed V2I safety applications were validated for more than 20 distinct scenarios and over 100 test runs using both light- and heavy-duty vehicles over a period of seven months. Subsequently, additional on-road testing of CSW on public roads and RSZW/LC in live work zones were conducted in Southeast Michigan.

Water vapor is, aside from carbon dioxide, the major fossil fuel combustion by-product. Depending on its concentration in the exhaust gas mixture as well as on the exhaust gas pressure, its condensation temperature can be derived. For typical gasoline engine stoichiometric operating conditions, the water vapor dew point lies at about 53 °C. The exhaust gas mixture does however contain some pollutants coming from the fuel, engine oil, and charge air, which can react with the water vapor and affect the condensation process. For instance, sulfur trioxide present in the exhaust, reacts with water vapor forming sulfuric acid. This acid builds a binary system with water vapor, which presents a dew point often above 100 °C. Exhaust composition after leaving the combustion chamber strongly depends on fuel type, engine concept and operation point. Furthermore, the exhaust undergoes several chemical after treatments.

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.

The regulations for mobile applications will become stricter in Euro 6 and further emission levels and require the use of active aftertreatment methods for NOX and particulate matter. SCR and LNT have been both used commercially for mobile NOX removal. An alternative system is based on the combination of these two technologies. Developments of catalysts and whole systems as well as final vehicle demonstrations are discussed in this study. The small and full-size catalyst development experiments resulted in PtRh/LNT with optimized noble metal loadings and Cu-SCR catalyst having a high durability and ammonia adsorption capacity. For this study, an aftertreatment system consisting of LNT plus exhaust bypass, passive SCR and engine independent reductant supply by on-board exhaust fuel reforming was developed and investigated. The concept definition considers NOX conversion, CO2 drawback and system complexity.

Even though a number of developed countries enjoy a high level of vehicle safety, more than 1.2 million fatalities still occur each year on roadways worldwide. There remains a need to continue improving vehicle and road safety. New technologies in sensors and electronic control units, and the growing knowledge of car-to-car and car-to-infrastructure technologies have led to a fusion of the previously separated areas of accident avoidance (popularly known as active safety) and mitigation of injuries (popularly known as passive safety) into the newer concept of integrated vehicle safety. This new approach represents a further step toward lowering accident rates. This book, written by two of the foremost automotive engineering safety experts, takes a unique and comprehensive approach to describing all areas of vehicle safety: accident avoidance, pre-crash, mitigation of injuries, and post-crash technologies, providing a solutions-based perspective of integrated vehicle safety.

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.

Synthetic fuels are expected to play an important role for future mobility, because they can be introduced seamlessly alongside conventional fuels without the need for new infrastructure. Thus, understanding the interaction of GTL fuels with modern engines, and aftertreatment systems, is important. The current study investigates potential benefits of GTL fuel in respect of diesel particulate filters (DPF). Experiments were conducted on a Euro 4 TDI engine, comparing the DPF response to two different fuels, normal diesel and GTL fuel. The investigation focused on the accumulation and regeneration behavior of the DPF. Results indicated that GTL fuel reduced particulate formation to such an extent that the regeneration cycle was significantly elongated, by ∼70% compared with conventional diesel. Thus, the engine could operate for this increased time before the DPF reached maximum load and regeneration was needed.

A new measurement system for dummy movement and chassis deformation in crash tests overcomes the restriction of blind areas in the existing photo camera observation. An inertial platform technique with micromechanical acceleration and rotation speed sensors is applied. Reconstruction of the original movement with tolerances of a few millimeters can be achieved. Various tests in automotive applications have demonstrated the performance and robustness of the system.

In one-dimensional engine simulation programs the simulation of engine performance is mostly done by parameter fitting in order to match simulations with experimental data. The extensive fitting procedure is especially needed for emissions formation - CO, HC, NO, soot - simulations. An alternative to this approach is, to calculate the emissions based on detailed kinetic models. This however demands that the in-cylinder combustion-flow interaction can be modeled accurately, and that the CPU time needed for the model is still acceptable. PDF based stochastic reactor models offer one possible solution. They usually introduce only one (time dependent) parameter - the mixing time - to model the influence of flow on the chemistry. They offer the prediction of the heat release, together with all emission formation, if the optimum mixing time is given.

Meeting current exhaust emission standards requires rapid catalyst light-off. Closed-coupled catalysts are commonly used to reduce light-off time by minimizing exhaust heat loss between the engine and catalyst. However, this exhaust gas system design leads to a coupling of catalyst heating and engine operation. An engine-independent exhaust gas aftertreatment can be realized by combining a burner heated catalyst system (BHC) with an underfloor catalyst located far away from the engine. This paper describes some basic characteristics of such a BHC system and the results of fitting this system into a Volkswagen Touareg where a single catalyst was located about 1.8 m downstream of the engine. Nevertheless, it was possible to reach about 50% of the current European emission standard EU 4 without additional fuel consumption caused by the BHC system.

The responses of the THOR and the Hybrid-III ATDs to head and neck loading due to a deploying air bag were investigated. Matched pair tests were conducted to compare the responses of the two ATDs under similar loading conditions. The two 50th percentile male ATDs, in the driver as well as the passenger positions, were placed close to the air bag systems, in order to enhance the interaction between the deploying air bag and the chin-neck-jaw regions of the ATDs. Although both ATDs nominally meet the same calibration corridors, they differ significantly in their kinematic and dynamic responses to interaction with a deploying air bag. The difference between the structural designs of the Hybrid-III's and the THOR's neck appears to result in significant differences in the manner in which the loads applied on the head are resisted.

The development of diesel powered passenger cars is driven by the enhanced emission legislation. To fulfill the future emission limits there is a need for advanced aftertreatment devices. A comprehensive study was carried out focusing on the improvement of the DOC as one part of these systems, concerning high HC/CO conversion rates, low temperature light-off behaviour and high temperature aging stability, respectively. The first part of this study was published in [1]. Further evaluations using a high temperature DPF aging were carried out for the introduced systems. Again the substrate geometry and the catalytic coating were varied. The results from engine as well as vehicle tests show advantages in a highly systematic context by changing either geometrical or chemical factors. These results enable further improvement for the design of the exhaust system to pass the demanding emission legislation for high performance diesel powered passenger cars.

A Robust Engineering experiment was performed to determine the effects PGM loading and placement on the FTP emissions of a 4 cylinder 2.4L and two 8 cylinder 4.7L vehicles. 1.3L catalytic converters were used containing a front and rear catalyst of equal volume. The experiment is defined by a Taguchi L-8 array. Eight different combinations of catalyst PGM loadings were aged and evaluated. Results show that nmHC and NOx emissions are predominately affected by the PGM loading of the front catalyst. The rear catalyst is insensitive to either Pt or Pd which can be used at low concentrations. Results also compare the benefits of Pd and Rh to reduce emissions. Confirmation runs suggest that significant reductions in PGM cost can be achieved over baseline designs.

Measuring vehicle exhaust volumetric flow rate accurately and precisely is critical in calculating the correct vehicle modal and bag mini-diluter exhaust emission constituent masses. It is also instrumental in engine calibration practices. Currently, DaimlerChrysler's Emission and Certification Lab in Auburn Hills, Michigan utilizes constant volume sampling bag systems to certify vehicles but the automotive technological trend is heading toward the bag mini-diluter for greater precision at low emission levels. The bag mini-diluters, as well as the modal sampling system, used extensively in vehicle development testing, rely on exhaust flow rate measurement by means of a direct vehicle exhaust flow meter named E-Flow. The E-Flow has few limitations such as flow profile instability at low idle flow rates and reaction to resonating pressure waves in the exhaust system.

At one time it was considered imperative to collect high frequency accelerometer data for accurate analysis. As a result current FMVSS regulations and SAE J2570 require the use of accelerometers with damping ratio of 0.05 or less (designated as undamped). This prevents the use of damped accelerometers for regulated channels. Damped accelerometers can provide comparable data and in some cases better data than undamped accelerometers, as long as they meet specific minimum requirements. To collect the most useful data, damped accelerometers should be added to the tool box of transducers used by crash test facilities.

A finite element model of the Transport Research Laboratory (TRL) honeycomb barrier, which is being proposed for use in vehicle compatibility studies, has been developed for use in LSDYNA. The model employs penalty parameters to enforce continuity between adjacent finite elements of the honeycomb barrier. Results of impact tests with indentors of various shapes and sizes were used to verify the performance of the computational model. Numerical simulations show reasonably good agreement with the test results.

Compatibility has been a passive safety research issue for many years. Great advancements in secondary (passive) safety have been achieved in the last decades through focussing on the self-protection level provided by passenger cars. The next step is to consider the other vehicle involved in the collision as well. Compatibility relates to the simultaneous improvement of both self- and partner- protection. Several tests procedures have been proposed around the world to assess the compatibility of passenger cars. None are considered ready to be implemented. This paper shows that controlling vehicle front-end geometry is the most feasible step to improve both self- and partner-protection. Through this, an increase in the structural interaction potential offered by passenger cars would result. To improve structural interaction, a convergence of front-end structures, to within certain vertical limits, is necessary.