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Highly automated driving (HAD) is under rapid development and will be available for customers within the next years. However the evidence that HAD is at least as safe as human driving has still not been produced. The challenge is to drive hundreds of millions of test kilometers without incidents to show that statistically HAD is significantly safer. One approach is to let a HAD function run in parallel with human drivers in customer cars to utilize a fraction of the billions of kilometers driven every year. To guarantee safety, the function under test (FUT) has access to sensors but its output is not executed, which results in an open loop problem. To overcome this shortcoming, the proposed method consists of four steps to close the loop for the FUT. First, sensor data from real driving scenarios is fused in a world model and enhanced by incorporating future time steps into original measurements.

The development of hydrogen-fueled vehicles has created the need for established fuel consumption testing methods. Until now the EPA has only accepted three methods of hydrogen fuel consumption testing, gravimetric, PVT (stabilized pressure, volume and temperature), and Coriolis mass flow; all of which necessitate physical measurements of the fuel supply [1]. BMW has developed an equation and subsequent testing methods to accurately and effectively determine hydrogen fuel consumption in light-duty vehicles using only exhaust emissions. Known as “Hydrogen-Balance”, the new equation requires no changes to EPA procedures and only slight modifications to most existing chassis dynamometers and CVS (Constant Volume Sampling) systems. The SAE 2008-01-1036, also written by BMW, explains the background as well as required equipment and changes to the CVS testing system. This paper takes hydrogen balance further by testing it against the three EPA established forms of fuel consumption.

The Hydrogen-Balance equation makes it possible to calculate the fuel economy or fuel consumption of hydrogen powered vehicles simply by analyzing exhaust emissions. While the benefits of such a method are apparent, it is important to discuss possible influencing factors that may decrease Hydrogen-Balance accuracy. Measuring vehicle exhaust emissions is done with a CVS (Constant Volume Sampling) system. While the CVS system has proven itself both robust and precise over the years, utilizing it for hydrogen applications requires extra caution to retain measurement accuracy. Consideration should be given to all testing equipment, as well as the vehicle being tested. Certain environmental factors may also play a role not just in Hydrogen-Balance accuracy, but as also in other low emission testing accuracy.

The effect of hydroforming on the mechanical properties and dynamic crush behaviors of tapered aluminum 6063-T4 tubes with octagonal cross section are investigated by experiments. First, the thickness profile of the hydroformed tube is measured by non-destructive examination technique using ultrasonic thickness gauge. The effect of hydroforming on the mechanical properties of the tube is investigated by quasi-static tensile tests of specimens prepared from different regions of the tube based on the thickness profile. The effect of hydroforming on the dynamic crush behaviors of the tube is investigated by axial crush tests under dynamic loads. Specimens and tubes are tested in two different heat treatment conditions: hydroformed-T4 (as-received) and T6. The results of the quasi-static tensile tests for the specimens in hydroformed-T4 condition show different amounts of work hardening depending on the regions, which the specimens are prepared from.

This paper presents the results of CFD study on sunroof buffeting suppression using a dividing bar. The role of a dividing bar in side window buffeting case was illustrated in a previous study [8]. For the baseline model of the selected vehicle in this study, a very high level of sunroof buffeting, 133dB, has been found. The CFD simulation shows that the buffeting noise can be significantly reduced if a dividing bar is installed at the sunroof. A further optimization study on the dividing bar demonstrates that the peak buffeting level can be reduced to 123dB for the selected vehicle if the dividing bar is installed at its optimal location, 65% of the total length from the front edge of the sunroof. The peak buffeting level can be further reduced to 100dB if the dividing bar takes its optimal width 80mm, 15% of the total length of the sunroof for this vehicle, while staying at its optimal location.

More than 200 tensile-shear resistance spot welded specimens were produced and tested to analyze the effect of spot weld spacing, weld size, sheet thickness, and adhesive on the ultimate strength of joints made from a mild hot dip galvannealed steel and an unexposed quality hot dip galvannealed 590 MPa minimum tensile strength dual phase steel (DP590). The geometric layout parameters were analyzed by a design of experiment (DOE) approach. The analysis showed that weld size is a primary factor affecting the strength of the joints for a given material. It was also determined that structural adhesive created a large relative strengthening for joints made from the mild steel. Interactions of the geometrical factors are also presented.

Although hydrogen ICE engines have existed in one sort or another for many years, the testing of fuel consumption by way of exhaust emissions is not yet a proven method. The current consumption method for gasoline- and diesel-fueled vehicles is called the Carbon-Balance method, and it works by testing the vehicle exhaust for all carbon-containing components. Through conservation of mass, the carbon that comes out as exhaust must have gone in as fuel. Just like the Carbon-Balance method for gas and diesel engines, the new Hydrogen-Balance equation works on the principle that what goes into the engine must come out as exhaust components. This allows for fuel consumption measurements without direct contact with the fuel. This means increased accuracy and simplicity. This new method requires some modifications to the testing procedures and CVS (Constant Volume Sampling) system.

The results of previous Life Cycle Assessments indicate the ecological dominance of the vehicle's use phase compared to its production and recycling phase. Particularly the so-called weight-induced fuel saving coefficients point out the great spectrum (0.15 to 1.0 l/(100 kg · 100 km)) that affects the total result of the LCA significantly. The objective of this article, therefore, is to derive a physical based, i.e. scientific chargeable and practical approved, concept to determine the significant parameters of a vehicle's use phase for the Life Cycle Inventory. It turns out that - besides the aerodynamic and rolling resistance parameters and the efficiencies of the power train - the vehicle's weight, the rear axle's transmission ratio and the driven velocity profile have an important influence on a vehicle's fuel consumption.

This paper describes a practical approach to extract the global static stiffness of a body in white (BIW) from dynamic measurements in free-free conditions. Based on a limited set of measured frequency response functions (FRF), the torsional and bending stiffness values are calculated using an FRF based substructuring approach in combination with inverse force identification. A second approach consists of a modal approach whereby the static car body stiffness is deduced from a full free-free modal identification including residual stiffness estimation at the clamping and load positions. As an extra important result this approach allows for evaluating the modal contribution of the flexible car body modes to the global static stiffness values. The methods have been extensively investigated using finite element modeling data and verified on a series of body in white measurements.

The National Renewable Energy Laboratory (NREL) collaborated with Millennium Cell and DaimlerChrysler to study heat and water management in a sodium borohydride (NaBH4) storage/processor used to supply hydrogen to a fuel cell in an automotive application. Knowledge of heat and water flows in this system is necessary to maximize the storage concentration of NaBH4, which increases vehicle range. This work helps evaluate the NaBH4 system's potential to meet the FreedomCAR program technical target of 6 wt% hydrogen for hydrogen storage technologies. This paper also illustrates the advantages of integrating the NaBH4 hydrogen processor with the fuel cell.

Automakers in the United States have started using bag mini-diluters (BMD) for developing, testing and certifying vehicles, to meet PZEV and SULEV regulation requirements. The BMD system which is a new technology developed by AIGER, is being used as an alternative to the traditional CFV/CVS system for accurate ultra low-level emission measurement. BMD system has shown to have considerable advantage over CFV/CVS system, especially at ULEV/SULEV emission levels. This paper details modifications and diagnostic checks conducted with the existing BMD system at the DaimlerChrysler Tech Center emissions facility, Auburn Hills, Michigan. This paper also discusses possible scenarios where the BMD system at DaimlerChrysler could give erroneous results due to system setup, optimization issues and equipment limitations.

The future of diesel-engine-powered passenger cars and light-duty vehicles in the United States depends on their ability to meet Federal Tier 2 and California LEV2 tailpipe emission standards. The experimental purpose of this work was to examine the potential role of fuels; specifically, to determine the sensitivity of engine-out NOx and particulate matter (PM) to gross changes in fuel formulation. The fuels studied were a market-average California baseline fuel and three advanced low sulfur fuels (<2 ppm). The advanced fuels were a low-sulfur-highly-hydrocracked diesel (LSHC), a neat (100%) Fischer-Tropsch (FT100) and 15% DMM (dimethoxy methane) blended into LSHC (DMM15). The fuels were tested on modern, turbocharged, common-rail, direct-injection diesel engines at DaimlerChrysler, Ford and General Motors. The engines were tested at five speed/load conditions with injection timing set to minimize fuel consumption.

Single-plane balancing is a very well-understood process, whereby an imbalance vector is determined and then opposed by a similar vector of equal magnitude but 180° out of phase. This is used in many situations to improve machine performance, vibration, noise etc. However, there is inherent in this process a sensitivity to errors of measurement and correction, since a large imbalance vector and the equally large correction vector must be of exactly equal magnitude and exactly 180° apart for perfect balance. This paper examines the effect of errors in measurement of the initial imbalance and correction of it on the residual balance of automotive drivelines. In particular, it examines the effects of the errors present in a system whereby a system balance correction is made, on a driveline assembly, at discrete points around a given plane (at bolt locations). Errors occur in measurement of vibration, in calculating correction masses and in applying those correction masses.

Today the worldwide convergence towards stricter fuel consumption and emission regulations is pushing carmakers and suppliers into new fields of innovation. Valeo Engine Cooling, VEC, is contributing towards these goals by applying its thermal management system expertise in order to reduce fuel consumption and emissions by using an advanced engine cooling system that incorporated variable speed PWM fans, an electric water pump and an electric water control valve. The paper discusses the benefits in terms of engine cooling, fuel economy and emissions over the FTP drive cycle. The paper gives some examples of advanced engine cooling strategies based on a virtual, predictive metal temperature sensor that is used to actuate the electrical water pump at the desired flow rate. The electrical balance between the 42V pump and fans has also been optimized to reduce the vehicle electrical power consumption and to keep the coolant temperature close to 110°C.

The vibration-generating mechanisms inside an engine are highly non-linear (combustion, valve operation, hydraulic bearing behavior, etc.). However, the engine structure, under the influence of these vibration-generating mechanisms, responds in a highly linear way. For the development and optimization of the engine structure for noise and vibration it is beneficial to use fast and ‘simple’ linear models, like linear FE-models, measured modal models or measured FRF-models. All these models allow a qualitative assessment of variants without excitation information. But, for true optimization, internal excitation spectra are needed in order to avoid that effort is spent to optimize non-critical system properties. Unfortunately, these internal excitation spectra are difficult to measure. Direct measurement of combustion pressure is still feasible, but crank-bearing forces, piston guidance forces etc. can only be identified indirectly.

Modern vehicles contain a multitude of networked electronics. This feature causes distributed functions in distributed electronics. Malfunctions occurring during EMC testing cannot be allocated precisely without detailed knowledge of the data streams. The electromagnetic environment during EMC-testing limits the possibilities of using standard solutions to detect these malfunctions. The paper will present a new tool, which is able to track the data streams in a CAN-Bus system during EMC-testing. By integrating EMC related parameters in the existing data stream of the vehicle's data bus, it is possible to keep a record of malfunctions as they occur.

Adding oxygenates to diesel fuel has shown the potential for reducing particulate (PM) emissions in the exhaust. The objective of this study was to select the most promising oxygenate compounds as blending components in diesel fuel for advanced engine testing. A fuel matrix was designed to consider the effect of molecular structure and boiling point on the ability of oxygenates to reduce engine-out exhaust emissions from a modern diesel engine. Nine test fuels including a low-sulfur (∼1 ppm), low-aromatic hydrocracked base fuel and 8 oxygenate-base fuel blends were utilized. All oxygenated fuels were formulated to contain 7% wt. of oxygen. A DaimlerChrysler OM611 CIDI engine for light-duty vehicles was controlled with a SwRI Rapid Prototyping Electronic Control System. The base fuel was evaluated in four speed-load modes and oxygenated blends only in one mode. Each operating mode and fuel combination was run in triplicate.

The overall program objectives were three fold: assess the benefits and limitations of oxygenated diesel fuels on engine performance and emissions identify oxygenates most suitable for potential use in future diesel formulations based on physico-chemical properties (e.g. flash point), toxicity, biodegradability and estimated cost of production perform limited emissions and performance testing of the oxygenated diesel blends select at least two oxygenated compounds for advanced engine testing In Part 1 of this program which is described in this paper, an extensive literature review was conducted to identify potential oxygenates for blending into diesel fuels. As many as 71 oxygenates were identified for the initial screening process. Based on a set of physical and chemical properties, a screening methodology was developed to select the 8 oxygenates that will be eligible for engine testing.

Traditional methods used to produce a die set (from developing initial machining cutter paths through finalized die tryout to produce a part that meets design intent) begin with draw simulation and development. It is here, traditionally, that scientific evaluation of actual metal stretch and theoretical ideals end. In past programs, a designed part would be simulated for stretch and a development model created to include various die compensations (i.e. springback, overcrown, etc.) based on past experience for area and amount. At this point, the die is cut and undergoes a metamorphosis through die tryout to finally produce a quality part. This is currently an open loop system. This paper will focus on the differences in the predicted way the die should look and the actual outcome (after part buyoff).

Most driver information systems offered in automobiles today display vehicle speed, fluid levels, fluid temperatures, and some basic diagnostic information (warnings, panel lamps). Optional driver information systems add to this list by offering fuel economy information, compass heading, outside temperature and other comfort and convenience related items. Very few provide information in regards to the real performance of the vehicle, its motion in 3-dimensional space, or the driver’s skill and performance. Making this information available to the driver can enhance the “fun-to-drive” aspects of driving.