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Current developments in automotive industry such as hybrid powertrains and the continuously increasing demands on emission control systems, are pushing complexity still further. Validation of such systems lead to a huge amount of test cases and hence extreme testing efforts on the road. At the same time the pressure to reduce costs and minimize development time is creating challenging boundaries on development teams. Therefore, it is of utmost importance to utilize testing and validation prototypes in the most efficient way. It is necessary to apply high levels of instrumentation and collect as much data as possible. And a streamlined data pipeline allows the fleet managers to get new insights from the raw data and control the validation vehicles as well as the development team in the most efficient way. In this paper we will demonstrate a data-driven approach for validation testing.

Catalyst systems utilizing ceramic and metallic substrates were compared to assess the influence of various substrate parameters on the exhaust gas conversion efficiency and flow restriction. In particular, the substrate surface area, substrate specific heat capacity, and substrate volume were all evaluated for their importance in estimating the conversion efficiency of the catalyst system. Additionally, substrate open frontal area and cell hydraulic diameter were compared against exhaust restriction performance.

A simple spring-mass model of the impact response of the side impact dummy (SID) is established. The spring and mass constants of the model are established through system identification methodology based on data from impact tests. The tests are performed in laboratory with hydraulically driven impactors impacting the chest and pelvis of the SID. The input data to the model consist of measured contact force or impactor velocity time histories, and the output data are accelerations on the rib, spine, and pelvis of the SID. The established model appears to predict the test results with reasonable accuracy. The main purpose of this study, however, is to use this simple model to carry out parametric studies of the response of the dummy with changing impact parameters, the result of which would be useful in understanding vehicle crash tests using the SID.

Trends towards lower vehicle fuel consumption and smaller environmental impact will increase the share of Diesel hybrids and Diesel Range Extended Vehicles (REV). Because of the Diesel engine presence and the ever tightening soot particle emissions, these vehicles will still require soot particle emissions control systems. Ceramic wall-flow monoliths are currently the key players in the Diesel Particulate Filter (DPF) market, offering certain advantages compared to other DPF technologies such as the metal based DPFs. The latter had, in the past, issues with respect to filtration efficiency, available filtration area and, sometimes, their manufacturing cost, the latter factor making them less attractive for most of the conventional Diesel engine powered vehicles. Nevertheless, metal substrate DPFs may find a better position in vehicles like Diesel hybrids and REVs in which high instant power consumption is readily offered enabling electrical filter regeneration.

Proper electric and thermal management of an HEV battery pack, consisting of many modules of cells, is imperative. During operation, voltage and temperature differences in the modules/cells can lead to electrical imbalances from module to module and decrease pack performance by as much as 25%. An active battery management system (BMS) is a must to monitor, control, and balance the pack. The University of Toledo, with funding from the U.S. Department of Energy and in collaboration with DaimlerChrysler and the National Renewable Energy Laboratory has developed a modular battery management system for HEVs. This modular unit is a 2nd generation system, as compared to a previous 1st generation centralized system. This 2nd generation prototype can balance a battery pack based on cell-to-cell measurements and active equalization. The system was designed to work with several battery types, including lithium ion, NiMH, or lead acid.

Future legislation, like EURO IV and EURO V or the US 2007 HD regulation will have massive reduction of particulate emission limits. For this beside improvement of engine combustion also exhaust aftertreatment systems are under investigation, like Diesel Particulate Filters (DPF), or Selective Catalytic Reduction (SCR) of Nitrogen Oxides. For all those tasks transient soot emission monitoring is one of the key features. To meet this demand a new device for the on-line measurement of soot emitted by combustion engines has been developed. Based on the photoacoustic principle, which has been optimized for automotive applications and easy use in test cells, the instrument shows a sensitivity of 5μg/m3, which is lower than current particulate immission standards in ambient air, and a time resolution of 1 sec. In the paper first the principles of measurement are shown, and then the specifications and results from measurements of very low soot concentration in the exhaust gas are presented.

Pure tone whine noises produced by transmission gear meshing can be a particular annoyance to vehicle occupants. In this case the gear meshing was exciting a resonance within the transaxle, resulting in an especially obtrusive pure tone noise within a narrow speed range. This report presents the identification of the resonating component and the development of a novel approach to eliminate the noise problem. Specifically a laminated steel (MPM) disk was fastened to the face of the gear to provide damping. Knowledge of the gear's mode of vibration was used to optimize the effectiveness of the damping treatment. This approach is proven to be effective via experimentally verified prototypes

The development process of a combustion engine is now a days strongly influenced by future emission regulations which require further reduction in fuel consumption and precise control of combustion process based on Intake air measurement, during engine development. Intake air flow meters clearly differentiate themselves from typical industrial gas flow meters because of their ability to measure extremely dynamic phenomenon of combustion engine. Thus, high internal data acquisition rate, short response time, ability to measure pulsating and reverse flows with lower measurement uncertainty are the factors that ensures the reliability of the results without being affected by ambient influences, sensor contamination or sensor aging. The AVL developed FLOWSONIX™ is based on ultrasonic transit time measuring principle with broad-band Capacitive Ultrasonic Transducer (CUT) characterized by an excellent air impedance matching strongly distinguishes itself by fulfilling all those requirements.

The reduction of particulate emissions limits requires new tools for the tuning of engines and exhaust aftertreatment systems. Time-resolved monitoring of low soot emissions is a key feature for such developments. The paper describes an improved photoacoustic soot sensor, and presents its applications for the characterization of transient exhaust soot emissions before and after Diesel emission after-treatment systems. The detection limit of the unit is around 5 μg/m3 soot, which is two orders of magnitude better than conventional time-resolved transmission measurement. Additionally, a wide dynamic range of four orders of magnitude can be achieved without range switching. The photoacoustic signal is proportional to the soot mass, no significant cross-sensitivities to gaseous absorbers were detected.

Stochastic simulation is used to account for the uncertainties inherent to the system and enables the study of crash phenomenon. For analytical purposes, random variables such as material crash properties, angle of impact, human response and the like can be characterized using statistical models. The methodology outlined in this approach is based on using the information about the probability of random variables along with structural behavior in order to quantify the scatter in the structural response. Thus the analysis gives a more complete picture of the actual simulation. Practical examples for the use of this technique are demonstrated and an overview of this approach is presented.

This paper describes a method for optimization of engine settings in view of best total cost of operation fluids. Under specific legal NOX tailpipe emissions requirements the engine out NOX can be matched to the current achievable SCR NOX conversion efficiency. In view of a heavy duty long haul truck application various specific engine operation modes are defined. A heavy duty diesel engine was calibrated for all operation modes in an engine test cell. The characteristics of engine operation are demonstrated in different transient test cycles. Optimum engine operation mode (EOM) selection strategies between individual engine operation modes are discussed in view of legal test cycles and real world driving cycles which have been derived from on-road tests.

The measurement of the particle number (PN) concentration of non-volatile particles ≻23 nm was introduced in the light-duty vehicles regulation; the heavy-duty regulation followed. Based on the findings of the Particle Measurement Program (PMP), heavy-duty inter-laboratory exercise, the PN concentration measurement can be conducted either from the full dilution tunnel with constant volume sampling (CVS) or from the partial flow dilution system (PFDS). However, there are no other studies that investigate whether the PN results from the two systems are equivalent. In addition, even the PMP study never investigated the uncertainty that is introduced at the final result from the extraction of a flow by a PN system from the PFDS. In this work we investigate the uncertainty for the three possible cases, i.e., considering a constant extracted flow from the PFDS, sending a signal with 1 Hz frequency to the PFDS, or feeding back the extracted flow to the PFDS.

Reductions of hardware costs as well as implementations of new innovative functions are the main drivers of today's automotive electronics. Indeed more and more resources are spent on adapting existing solutions to different environments. At the same time, due to the increasing number of networked components, a level of complexity has been reached which is difficult to handle using traditional development processes. The automotive industry addresses this problem through a paradigm shift from a hardware-, component-driven to a requirement- and function-driven development process, and a stringent standardization of infrastructure elements. One central standardization initiative is the AUTomotive Open System ARchitecture (AUTOSAR). AUTOSAR was founded in 2003 by major OEMs and Tier1 suppliers and now includes a large number of automotive, electronics, semiconductor, hard- and software companies.

Two active boom noise damping techniques using a Helmholtz resonator-based compensator and a lead compensator called a positive pressure feedback have been developed at the University of Dayton [1]. The two damping techniques are of feedback type and their compensators can be implemented in software or hardware (using inexpensive operational amplifiers). The active damping system would rely on a speaker, a low-cost microphone, two accelerometers, and an electronic circuit (or a micro-controller) to add damping to the offending low-frequency vibroacoustic modes of the cavity. The simplicity of the active boom noise damping system lends itself to be incorporated into a vehicle's sound system. The Helmholtz resonator-based strategy is implemented on a Dodge Durango sport utility vehicle. The control scheme adds appreciable amount of damping to the first cavity mode and the first structurally induced acoustic mode of the cabin.

Eliminating toxic exhaust emissions, amongst them particulate matter (PM), is one of the driving factors behind the increasing use of electrified vehicles. However, it is frequently overseen that PM arise not only from combustion, but from non-exhaust traffic related causes as well; in particular from the vehicle brakes, tires and the road surface. Furthermore, as electrified vehicles weigh more and typically exhibit higher torques at low speeds, their non-exhaust emissions tend to be higher than for comparable conventional vehicles, especially those generated by tires. Fortunately, tire related emissions are directly related to tire wear, so that limiting tire wear can reduce these emissions as well. This can be accomplished by intelligently modulating the vehicle torque profile in real time, to limit the operation in conditions of higher tire wear.

A calibration and validation workflow will be presented in this paper, which utilizes common static global models for fuel consumption, NOx and soot. Due to the applicability for warm-up tests, e.g. New European Driving Cycle (NEDC), the models need to predict the temperature influence and will be fitted with measuring data from a conditioned engine test bed. The applied model structure consisting of a number of global data-based sub-models is configured especially for the requirements of multi-injection strategies of common rail systems. Additionally common global models for several constant coolant water temperature levels are generated and the workflow tool supports the combination and segmentation of global nominal map with temperature correction maps for seamless and direct ECU setting.

This paper presents an energy relationship between vehicle impact pulses and restraint systems and applies the relationship to formulations of response factors for linear and nonlinear restraints. It also applies the relationship to derive optimal impact pulses that minimize occupant response for linear and nonlinear restraints. The relationship offers a new viewpoint to impact pulse optimization and simplifies the process mathematically. In addition, the effects of different vehicle impact pulses on the occupant responses with nonlinear restraints are studied. Finally, concepts of equivalent pulses and equal intensity pulses are presented for nonlinear restraints.

As emission regulations become tighter and tighter, equipment must evolve to be able to achieve the new standards. Also additional test requirements demand a system that is flexible and can accommodate differences both in the tests and the test facility. By that test cell equipment for chassis dynamometer as well as engine dynamometer applications is getting increasingly complex. That also will require new concepts for the design of such systems. In the past emission system design was more likely a collection and packaging process, which has interfaced various independent components. Now, the development of modern analytical emission systems requires a true holistic design process. This paper will describe the demands and the realization of a modern emission system. It can be shown that an extended effort during the design process will result in a high performance system, which still remains simple and robust.

With the increased number of variants, the preservation of a brand-specific vehicle DNA becomes more and more important. Paired with growing customer expectations, brand DNA can be a crucial point in the decision-making process of buying a new vehicle. Whereas the customer will assess the DNA subjectively during driving by evaluating the vehicle drive quality (“driveability”), most manufacturers are not merely relying on subjective evaluations by having test drivers perform maneuvers with prototype vehicles. Nowadays, the assessment is performed objectively during the vehicle development process. As a supporting measure, the Anstalt für Verbrennungskraftmaschinen List (AVL) has made the objective assessment tool AVL-DRIVE commercially available. Up to now, the AVL-DRIVE ratings had to be manually analyzed and checked for outliers. Low ratings and high deviations to a priori specified target values are a good starting point for the search of outliers.

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.