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Main topics are the development and the build-up of an 18ton hybrid truck with a parallel hybrid drivetrain. With this truck it is possible to drive up to 3 kilometers in the pure electric driving mode. Presenter Andreas Eglseer, Engineering Center Steyr GmbH & Co. KG

There are now a wide variety of Hybrid and Electric Vehicles in or near production. They reduce or displace petroleum consumption with of various combinations of conventional IC engine, mechanical transmission, liquid fuel storage, electrical energy storage, electrical and electro-mechanical energy conversion, and vehicle-to-grid energy interface. These Electrified types of vehicles include Mild Hybrid, Full Hybrid, Plug-In Hybrid, Extended Range Electric, and Battery Electric. Some types differ in their actual usability for the real mixes of driving trips, and further that differ in their effectiveness to reduce or displace fuel in actual real world driving use. Vehicle size is also a factor in total vehicle utility in transporting people. If we may segment drivers by their driving needs, in each segment, we see a particular type of electrified vehicle that is better suited than others at minimizing fuel cost and petroleum consumption for the purposes of transporting people.

FlexRay is a time triggered automotive communication protocol that connects ECUs (Electronic Control Units) on which distributed automotive applications are executed. If exact agreement (e.g. on physical values measured by redundant sensors on different ECUs) must be reached in the presence of asymmetric communication faults, a byzantine agreement protocol like Signed Messages (SM) can be utilized. This paper gives examples of how byzantine faults can emerge in a FlexRay-based system and proposes optimizations for a FlexRay-specific implementation of the SM protocol. The protocol modifications allow for a reduction in the number of protocol messages under a slightly relaxed fault model, as well as for a reduction in the number of messages to be temporarily stored by the ECUs.

Quasi-static tensile properties of TRIP590 steels from three different manufacturers were investigated using digital image correlation (DIC). The focus was on the post-uniform elongation behavior which can be very different for steels of the same grade owing to different manufacturing processes. Miniature tensile specimens, cut at 0°, 45°, and 90° relative to the rolling direction, were strained to failure in an instrumented tensile stage. True stress-true strain curves were computed from digital strain gages superimposed on digital images captured from one gage section surface during tensile deformation. Microstructural phases in undeformed and fracture specimens were identified with optical microscopy using the color tint etching process. Fracture surface analyses conducted with scanning electron microscopy and energy dispersive spectroscopy were used to investigate microvoids and inclusions in all materials.

The SAE Fuel Cell Vehicle (FCV) Safety Working Group has been addressing FCV safety for over 9 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable as a Recommended Practice for FCV development with regard to the identification of hazards and the definition of countermeasures to mitigate these hazards such that FCVs can be operated in the same manner as conventional gasoline internal combustion engine (ICE)-powered vehicles. SAE J2578 is currently being revised so that it will continue to be relevant as FCV development moves forward. For example, test methods were refined to verify the acceptability of hydrogen discharges when parking in residential garages and commercial structures and after crash tests prescribed by government regulation, and electrical requirements were updated to reflect the complexities of modern electrical circuits which interconnect both AC and DC circuits to improve efficiency and reduce cost.

Regulations have been established for the monitoring and reporting of greenhouse gas (GHG) emissions and fuel consumption from the transport sector. Low carbon fuels combined with new powertrain technologies have the potential to provide significant reductions in GHG emissions while decreasing the dependence on fossil fuel. In this study, a lean-burn ethanol-diesel dual-fuel combustion strategy has been used as means to improve upon the efficiency and emissions of a conventional diesel engine. Experiments have been performed on a 2.0 dm3 single cylinder heavy-duty engine equipped with port fuel injection of ethanol and a high-pressure common rail diesel injection system. Exhaust emissions and fuel consumption have been measured at a constant engine speed of 1200 rpm and various steady-state loads between 0.3 and 2.4 MPa net indicated mean effective pressure (IMEP).

To cope with the increasing number of advanced features (e.g., smart-phone integration and side-blind zone alert.) being deployed in vehicles, automotive manufacturers are designing flexible hardware architectures which can accommodate increasing feature content with as fewer as possible hardware changes so as to keep future costs down. In this paper, we propose a formal and quantitative definition of flexibility, a related methodology and a tool flow aimed at maximizing the flexibility of an automotive hardware architecture with respect to the features that are of greater importance to the designer. We define flexibility as the ability of an architecture to accommodate future changes in features with no changes in hardware (no addition/replacement of processors, buses, or memories). We utilize an optimization framework based on mixed integer linear programming (MILP) which computes the flexibility of the architecture while guaranteeing performance and safety requirements.

General Motors (GM) recently purchased an acoustic holography system based on the Helmholtz Equation Least Squares (HELS) methodology. Typically acoustic holography has utilized planar transformation of the Fourier acoustic equations. General Motors conducted a variety of experiments on a simple well understood structure. This enabled us to understand the setup parameters and confirm the manufacturer's claims for accuracy. Measurements on the structure were taken using the HELS based equipment and a laser vibrometer. Conclusions are drawn on how to set up the equipment for future testing on vehicles.

Cold start vehicle driveability performance depends on many parameters, one of which is the distillation character of the fuel. In the late 90's, a gasoline driveability index (DI) was developed for spark ignited combustion vehicles by a consortium of automotive and petroleum industry scientists based on correlation studies between controlled fuel quality matrices and vehicle performance under specific ambient conditions. The DI equation uses a weighted sum of gasoline distillation temperatures at the 10, 50 and 90 percent evaporation volumes, commonly called T10, T50 and T90. These three distillation volatility points are specified by the ASTM International D 4814 fuel specification and are seasonally adjusted. This paper studies the cold start driveability performance of Federal EPA Bin 5 and Bin 8 vehicles with respect to fuel distillation characteristics at temperatures other than T10, T50 and T90.

The need for improved axle NVH integration has increased significantly in recent years with industry trends toward full-time and automatic four wheel drive (4wd) systems. Along with seamless 4wd operation, quiet performance has become a universal expectation. Axle gear-mesh noise can be transmitted to the vehicle passenger compartment through airborne paths (not discussed in this paper) and structure-borne paths (the focus of this paper.) A variety of mounting configurations are used in an attempt to provide improved axle isolation and reduce structure-borne transmission of gear-mesh noise. The configuration discussed in this paper is a 4-point vertical mount design for an Independent Front Drive Axle (IFDA). A significant benefit of this configuration is improved isolation in the range of drive torques where axle-related NVH issues typically exist.

Friction Launch transmissions use a wet multi-plate clutch to replace the torque converter in an automatic transmission. By using one of the range clutches inside the transmission, the benefits of this integrated friction launch technology (IFL), such as reduction in mass, packaging, and cost, can be enhanced. The availability of new automatic transmissions with higher number of speeds and wider ratio spreads makes IFL technology more viable than ever before. The new GM Rear-Wheel-Drive (RWD) six-speed transmission has paved the way for a full implementation of integrated friction launch technology in a GM full size Sport-Utility Vehicle (SUV). This project focuses on both hardware and control issues with the friction launch clutch. The hardware issues include designing the clutch for launch energy, cooling, and durability.

The objective of this paper is to propose a new model in the identification of a contributing factor to the generation of Radio Frequency Interference (RFI) due to the operation of a spark-ignited engine. This model incorporates parameters in the electrical operation of the ignition system components and their interaction with the engine mechanical structure, which is also used as a circuit component (the ignition system “ground”). T he model was developed as a result of analysis of numerous studies that have been conducted over the years in an attempt to identify why RFI characteristics can differ when using identical components on different engines, or locating the components in different locations on identical engines. This situation is a problem due to the resulting uncertainty with respect to the determination of what is the optimum vehicle ignition system configuration to meet all electrical and RFI or electromagnetic compatibility (EMC) requirements.

This paper discusses radio usage habits observed during analysis of 700 hours of video sampled from the 100-Car Naturalistic Driving Study database. Analysts used large-scale printouts of each vehicle's radio faceplate and recorded interactions based on video analysis of hand movement and location (without the assistance of audio recordings). The duration and specific manipulations or adjustments were recorded for each interaction. The results summarize the length and type of interactions, most often-used controls, and total percentage of time drivers interacted with the radio.

Limited-slip differentials improve traction and handling when compared to open differentials, but offer no active modulation and can compromise typical driving. A number of passive control systems exist that attempt to reduce this compromise. Electronically controlled limited-slip differentials (eLSD) are being introduced that allow active control of the differential in all driving situations and can be operated as an open differential, a fully locked differential, or at any point between these extremes. Such an eLSD system was implemented in two General Motors front wheel drive cars-one on an automatic transmission and applied by the transmission pump, the other on a manual transmission and applied by an external pump. This eLSD system contains a multi-plate wet clutch connected to the differential carrier and right side half-shaft of an all wheel drive capable transmission.

The Hydra-Matic 6T70 is General Motors first model of a new, two-variant front wheel drive (FWD) six speed automatic transmission family. The second variant is a higher capacity model, the 6T75. The transmission was co-developed with Ford Motor Company. The 6F50 is the Ford variant that aligns with the GM 6T70 transmission. Approximately eighty five percent of the hardware is shared or common between the GM and Ford transmission variants. Ford will also have a higher capacity variant the 6F55 to align with the GM 6T75. The first GM application is the Saturn Aura for the 2007 Model Year. The Ford Edge and Lincoln MKX in MY 2007 will be the first applications for the 6F50. While the Hydra-Matic and Ford FWD six-speed family was designed with two variants in mind, the designed in modularity requires only changes to the second and third axis and case housings depending on specific torque requirements. This modular design enables a tremendous amount of part sharing.

In the North American automotive market, cylinder deactivation by means of engine valve deactivation is becoming a significant enabler in reducing the Brake Specific Fuel Consumption (BSFC) of large displacement engines. This allows for the continued market competitiveness of large displacement spark ignition (SI) engines that provide exceptional performance with reduced fuel consumption. As an alternative to a major engine redesign, the Active Fuel Management™ (AFM™) system is a lower cost and effective technology that provides improved fuel economy during part-load conditions. Cylinder deactivation is made possible by utilizing innovative new base engine hardware in conjunction with an advanced control system. In the GM 3.9L V-6 Over Head Valve (OHV) engine, the standard hydraulic roller lifters on the engine's right bank are replaced with deactivating hydraulic roller lifters and a manifold assembly of oil control solenoids.

An automatic transmission control system for clutch-to-clutch shifting systems has been developed. This enables the new General Motors Powertrain families of rear- and front-wheel drive transmissions to meet stringent cost, mass, and packaging reqiurements, while providing driveability and fuel economy improvements over the four- and five-speed transmissions that they replace. The design team utilized several new technologies and methods to robustly engineer a control system that allowed excellent first time capability and reduced calibration intensity. Innovative technical approaches were developed in several key mechatronics areas.

The objective of this paper is to propose that the automotive engineering “legacy” approach of assuming that vehicle electrical return paths using conductive structural components have zero (0) ohms of impedance, needs to be reviewed. The process in this review consists of the development of an equivalent circuit composed of both real (“resistive”) and reactive elements (due to inductance and capacitance). This issue needs to be addressed due to the increased complexity of electrical and electronics systems in vehicles and the use of the vehicle structural (such as chassis, frame, or bracket) components to provide a path for the return of electrical power and/or signals as a way to eliminate additional wiring manufacturing issues, cost, and weight contribution to a vehicle.

The unsteady flow fields behind two different automobile outside side rear view mirrors were examined experimentally in order to obtain a comprehensive data base for the validation of the ongoing computational investigation effort to predict the aero-acoustic noise due to the outside rear view mirrors. This study is part of a larger scheme to predict the aero-acoustic noise due to various external components in vehicles. To aid with the characterization of this complex flow field, mean and unsteady surface pressure measurements were undertaken in the wake of two mirror models. Velocity measurements with particle image velocimetry were also conducted to develop the mean velocity field of the wake. Two full-scale mirror models with distinctive geometrical features were investigated.

Aromatics, cetane number, density, and lubricity of a large number of retail diesel fuel samples were compared before, during, and after the switch from low sulfur to ultra low sulfur diesel fuel. Also, sulfur and nitrogen speciation was done on a small set of samples to determine the changes in heterocyclic compounds as refiners made the switch. For ultra low sulfur fuel, total aromatics decreased substantially, density decreased slightly, cetane number increased by about 1 - 2 numbers, and lubricity (wear scar) improved slightly relative to low sulfur diesel fuel. Speciation results showed that hydrotreating eliminated thiophenes and benzothiophenes from the fuel. The only sulfur species remaining were dibenzothiophenes, and these were present at very low part per million levels. Nitrogen compounds in the form of carbazoles were either eliminated or reduced to low part per million levels.