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Technical Paper

Side Mirror Soiling Investigation through the Characterization of Water Droplet Formation and Size behind a Generic Plate

2024-02-27
2024-01-5030
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.
Technical Paper

Development of Wireless Message for Vehicle-to-Infrastructure Safety Applications

2018-04-03
2018-01-0027
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.
Technical Paper

Validating Prototype Connected Vehicle-to-Infrastructure Safety Applications in Real- World Settings

2018-04-03
2018-01-0025
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.
Technical Paper

Precise Dummy Head Trajectories in Crash Tests based on Fusion of Optical and Electrical Data: Influence of Sensor Errors and Initial Values

2015-04-14
2015-01-1442
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.
Book

Integrated Automotive Safety Handbook

2013-10-08
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.
Technical Paper

Simulation Based Analysis of Test Results

2010-04-12
2010-01-1013
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.
Journal Article

Motion Tracking in Crash Test Applications with Inertial Measurement Units

2009-04-20
2009-01-0056
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.
Technical Paper

Required Measures to Improve the Structural Interaction Potential of Passenger-Cars

2005-04-11
2005-01-1351
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.
Technical Paper

Feasible Steps towards Improved Crash Compatibility

2004-03-08
2004-01-1167
Compatibility has been a research issue for many years now. It has gained more importance recently due to significant improvements in primary and secondary safety. Using a rigorous approach, combining accident research and theoretical scientific considerations, measures to improve vehicle-vehicle compatibility, with an emphasis on feasibility, were discussed. German accident research statistics showed that frontal impacts are of higher statistical significance than side impacts. Based on this and the high potential for improvement due high available deformation energy, the frontal impact configuration was identified as the most appropriate collision mode for addressing the compatibility issue. In side impacts, accident avoidance was identified as the most feasible and sensible measure. For frontal vehicle-vehicle impacts, both trucks and passenger cars were identified as opponents of high statistical significance.
Technical Paper

Optical Coordinate Measuring Techniques for the Determination and Visualization of 3D Displacements in Crash Investigations

2003-03-03
2003-01-0891
The measurement of 3D coordinates using optical techniques is well known for more than 50 years. Today, modern photogrammetric systems are based on handheld digital cameras and are used to identify the location of any circular marker or feature on the object's surface. The ease of use and the accurate and automated derivation of 3D coordinates from 2D digital images helped to establish a powerful tool for position control, assembly checks and reverse engineering. A new application is the analysis of real vehicle crashes. The location of hundreds of markers on the damaged vehicle can easily be determined in vehicle body position. These coordinates are being compared to the undeformed geometry and provide herby 3D information on any displacement. Using reverse engineering techniques, surfaces are created from the 3D points and thus a 3D model of the crashed vehicle is available for an easy visualization of the deformation.
Technical Paper

Research Results and Progress in LeaNOx II -A Co-operation for Lean NOx Abatement

2000-10-16
2000-01-2909
In a consortium of European industrial partners and research institutes, a combination of industrial development and scientific research was organised. The objective was to improve the catalytic NOx conversion for lean burn cars and heavy-duty trucks, taking into account boundary conditions for the fuel consumption. The project lasted for three years. During this period parallel research was conducted in research areas ranging from basic research based on a theoretical approach to full scale emission system development. NOx storage catalysts became a central part of the project. Catalysts were evaluated with respect to resistance towards sulphur poisoning. It was concluded that very low sulphur fuel is a necessity for efficient use of NOx trap technology. Additionally, attempts were made to develop methods for reactivating poisoned catalysts. Methods for short distance mixing were developed for the addition of reducing agent.
Technical Paper

Accident Analysis and Measures to Establish Compatibility

1999-03-01
1999-01-0065
The vehicle fleet differs in mass, geometry, stiffness and many other parameters. These differences are consequences of different design objectives for these vehicles and result from consumer demand, environmental and safety considerations etc. Accident research shows that the injury outcome differs in some cases, when two vehicles collide. Scientists often discuss a list of features that are assumed to be relevant for compatibility of vehicles. The relevance of these potentially important compatibility features and expected compatibility measures is examined from the perspective of accident analysis. An overview of this accident research is given and crash tests and measures are discussed that correspond with these findings.
Technical Paper

Human Factors Data in Relation to Whiplash Injuries in Rear End Collisions of Passsenger Cars

1998-03-01
981191
Cervical Spine Distortions (CSD) - sometimes called whiplash injuries - have turned out in passenger car accidents to be one of the most important types of injuries to occupants, according to the rate of occurences and to the significance of consequences as well. Many technical aspects of traffic accidents which in the past have led to CSD have been analysed and reported in a large number of publications. However human factors data are not as good represented in the literature. Particularly these parameters and their relationship to whiplash injuries have been analysed on the basis of the Volkswagen Accident Database. The significance of the items gender, age, body height and body weight of belted occupants in passenger cars involved in rear end collisions is presented in quantitative terms regarding frequencies of occurance and risk of suffering CSD respectively.
Technical Paper

Quantitative In-Cylinder NO LIF Measurements with a KrF Excimer Laser Applied to a Mass-Production SI Engine Fueled with Isooctane and Regular Gasoline

1997-02-24
970824
Quantitative 1-D spatially-resolved NO LIF measurements in the combustion chamber of a mass-production SI engine with port-fuel injection using a tunable KrF excimer laser are presented. One of the main advantages of this approach is that KrF laser radiation at 248 nm is only slightly absorbed by the in-cylinder gases during engine combustion and therefore it allows measurements at all crank angles. Multispecies detection turned out to be crucial for this approach since it is possible to calculate the in-cylinder temperature from the detected Rayleigh scattering and the simultaneously acquired pressure traces. Additionally, it allows the monitoring of interfering emissions and spectroscopic effects like fluorescence trapping which turned out to take place. Excitation with 248 nm yields LIF emissions at shorter wavelengths than the laser wavelength (at 237 and 226 nm).
Technical Paper

New Developments in Lean NOx Catalysis for Gasoline Fueled Passenger Cars in Europe

1996-10-01
962047
There is an increasing interest in running gasoline fueled passenger cars lean of stoichiometric air to fuel (A/F) ratio to improve fuel economy. These types of engines will operate at lean A/F ratios during cruising at partial load and return to stoichiometric or even rich conditions when more power is required. The challenge for the engine and catalyst manufacturer is to develop a system which will combine the high activity rates of a state-of-the-art three way catalyst (TWC) with the ability to reduce nitrogen oxides (NOx) under excess of oxygen. The target is to achieve the future legislation limits (EURO III/IV) in the European Union. Recent developments in automotive pollution control catalysis have shown that the utilization of NOx adsorption materials is a suitable way for reduction of NOx emissions of gasoline fueled lean burn engines.
Technical Paper

Effect of EGR on Spray Development, Combustion and Emissions in a 1.9L Direct-Injection Diesel Engine

1995-10-01
952356
The spray development, combustion and emissions in a 1.9L optical, four-cylinder, direct-injection diesel engine were investigated by means of pressure analysis, high-speed cinematography, the two-colour method and exhaust gas analysis for various levels of exhaust gas recirculation (EGR), three EGR temperatures (uncontrolled, hot and cold) and three fuels (diesel, n-heptane and a two-component fuel 7D3N). Engine operating conditions included 1000 rpm/idle and 2000 rpm/2bar with EGR-rates ranging from 0 to 70%. Independent of rate, EGR was found to have a very small effect on spray angle and spray tip penetration but the auto-ignition sites seemed to increase in size and number at higher EGR-rates with associated reduction in the flame luminosity and flame temperature, by, say, 100K at 50% EGR.
Technical Paper

A New Method to Assess the Summer Suitability of Car Seats

1993-03-01
930106
A new method has been designed to examine car seats by technical means only, whether they fit summer conditions or not. Test procedures start with the application of a carefully wetted cloth onto the seat to be examined. The test area is then covered by a temperature controlled, electrically heated solid body bloc. This simulates the body temperature and the seat pressure of a real seat user. During test periods of standard three hours, temperature and humidity is measured beneath the test device and in the surrounding air. As an effect of the water impulse the humidity increases under the body bloc. It has been proved that good summer suitability of a car seat is characterised by moderate amount and moderate duration of increased humidity readings. Poor suitability results in higher amount and longer duration of raised humidity. The method is shown to be useful to examine full scale car seats, child safety seats and single design characteristics of car seats as well.
Technical Paper

Effectiveness of Seat Belts - Analysis of Real World Accidents of Volkswagen Vehicles

1987-07-01
870223
Generally, safety belt effectiveness is spoken of as a single value which is applied to all types of accidents and injuries. This study analyzes the makeup of safety belt effectiveness and compares the overall effectiveness to the effectiveness for different levels of injury, different areas of the body and for different types of accidents at different speeds. These comparisons show the wide range of effectiveness of safety belts and the relative effectiveness for different specific situations.
Technical Paper

Development of a Rigid Passenger Safety Compartment Made of Composite Material-Application for Front Door Frames

1986-03-01
860278
Based an extensive preparatory work and analyses, suggestions have been drawn up with regard to solutions for front door frames in the following regions:- door hinge mountings, seat belt anchorage mountings of B pillars, cross sections for the top of A pillars. At the same time as the design work, FEM calculations should be carried out to ensure optimization of the concepts. Economy reasons and experiences in production runs point towards a very strong fibre glass-reinforced door frames manufacutred in the SMC procress. The complete door frame is examined in comparison with geometrically similar sheet metal parts on a test frame and in the vehicle.
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