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The permanently increasing number of convenience and safety functions leads to higher complexity of in-car electronics and the rapidly growing amount of sensors, actuators and electronic control units places higher demands on high- speed data communication protocols. Safety-critical systems need deterministic protocols with fault-tolerant behavior. The need for on-board diagnosis calls for flexible use of bandwidth and an ever-increasing number of functions necessitates a flexible means of extending the system. None of the communication solutions available on the market until now (like CAN or TTP) have been able to fulfill all these demands. To solve these problems, BMW together with several semiconductor companies has developed a new protocol for safety-critical applications in automotive vehicles.

A new simulation tool was established and approved by TRW as part of the continuous improvement of the development process. This tool allows the OEM and the system supplier to keep high quality even with further reduced development times. The introduction of the tool in a side air-bag development program makes it possible to ensure high development confidence with a reduced number of vehicle crash tests and late availability of interior component parts.

The worldwide automotive industry is currently preparing for a market introduction of hydrogen-fueled powertrains. These powertrains in fuel cell electric vehicles (FCEVs) offer many advantages: high efficiency, zero tailpipe emissions, reduced greenhouse gas footprint, and use of domestic and renewable energy sources. To realize these benefits, hydrogen vehicles must be competitive with conventional vehicles with regards to fueling time and vehicle range. A key to maximizing the vehicle's driving range is to ensure that the fueling process achieves a complete fill to the rated Compressed Hydrogen Storage System (CHSS) capacity. An optimal process will safely transfer the maximum amount of hydrogen to the vehicle in the shortest amount of time, while staying within the prescribed pressure, temperature, and density limits. The SAE J2601 light duty vehicle fueling standard has been developed to meet these performance objectives under all practical conditions.

In studying H2S emissions, it is desirable to have an analytical technique which is rapid, continuous, accurate and easy to use in a laboratory or vehicle exhaust environment. Typically, H2S has been measured using the EPA impinger method with collection times on the order of 1 to 2 minutes. Other techniques have been developed with significantly shorter response times. However, it has been shown that the major release of H2S occurs in less than 20 seconds after a vehicle changes from rich to lean operation. Therefore, it is highly desirable to have an H2S analytical technique with a response time of less than 10 seconds. In this paper, the benefits of use of a chemical ionization mass spectrometer (CIMS) to continuously monitor H2S and SO2, emissions are reported. Using the CIMS technique, the effects of several operating parameters on the release of H2S and SO2 from automotive catalysts were studied.

It is essential to include uncertainties in the simulation process in order to perform reliable vibroacoustic predictions in the early design phase. In this contribution, uncertainties are quantified using the generalized Polynomial Chaos (gPC) expansion in combination with a Finite Element (FE) model of a vehicle body in white. It is the objective to particularly investigate the applicability of the gPC method in the industrial context with a high number of uncertain parameters and computationally expensive models. A non-intrusive gPC expansion of first and second order is implemented and the approximation of a stochastic response process is compared to a Latin Hypercube sampling based reference solution with special regard to accuracy and computational efficiency. Furthermore, the method is examined for other input distributions and transferred to another FE model in order to verify the applicability of the gPC method in practical applications.

The potential to reduce the cost of embedded software by standardizing the application behavior for Automotive Body and Comfort domain functions is explored in this paper. AUTOSAR, with its layered architecture and a standard definition of the interfaces for Body and Comfort application functions, has simplified the exchangeability of software components. A further step is to standardize the application behavior, by developing standard specifications for common Body and Comfort functions. The corresponding software components can be freely exchanged between different OEM/Tier-1 users, even if developed independently by multiple suppliers. In practice, individual OEM users may need to maintain some distinction in the functionality. A method of categorizing the specifications as ‘common’ and ‘unique’, and to configure them for individual applications is proposed. This allows feature variability by means of relatively simple adapter functions.

A joint study was conducted between BMW and Goodyear with the objective of analysing the cause and identifying methods to reduce the structure-borne interior noise in a vehicle driving on rough road surfaces. A vibro-acoustic characterization of the car was performed by measuring the car vibro-acoustic transfer functions and by using a transfer path analysis technique to identify the main suspension parts affecting the interior noise at target frequencies. The vibration transmissibility characteristics of the tire were measured and also simulated by Finite Element in [1-200Hz] frequency range. The vibro-acoustic interaction between the tire and car sub-systems was examined. A Finite Element sensitivity analysis was used to define and build new prototype tires. A 3dB(A) interior noise improvement was obtained with these new tires at target frequencies.

Timing evaluation methods help to design a robust and extendible E/E architecture (electric/electronic). BMW has introduced the systematic application of such methods in the E/E design process within the last three years. Meanwhile, most of the architectural changes are now verified by a tool-based, automatic real-time analysis. This has increased the accuracy of the network planning and productivity of the BMW network department. In this paper, we give an overview of the actual status of timing evaluations in BMW's E/E architecture design. We discuss acceptance criteria, analysis metrics, and design rules, as far as these are related to timing. We look specifically at automation options, as these improve the productivity further. We will see that timing analysis has matured and should be mandatory for application in mass production E/E architecture development. At the same time, there is room for future improvements.

The reduction of vehicle exhaust particle emissions is a success story of European legislation. Various particle number (PN) counters and calibration procedures serve as tools to enforce PN emission limits during vehicle type approval (VTA) or periodical technical inspection (PTI) of in-use vehicles. Although all devices and procedures apply to the same PN-metric, they were developed for different purposes, by different stakeholder groups and for different target costs and technical scopes. Furthermore, their calibration procedures were independently defined by different stakeholder communities. This frequently leads to comparability and interpretation issues. Systematic differences of stationary and mobile PN counters (PN-PEMS) are well-documented. New, low-cost PTI PN counters will aggravate this problem. Today, tools to directly compare different instruments are scarce.

The Energy and Environment Test Centre (EVZ) is a complex comprising three large climatic wind tunnels, two smaller test chambers, nine soak rooms and support infrastructure. The capabilities of the wind tunnels and chambers are varied, and as a whole give BMW the ability to test at practically all conditions experienced by their vehicles, worldwide. The three wind tunnels have been designed for differing test capabilities, but share the same air circuit design, which has been optimized for energy consumption yet is compact for its large, 8.4 m₂, nozzle cross-section. The wind tunnel test section was designed to meet demanding aerodynamic specifications, including a limit on the axial static pressure gradient and low frequency static pressure fluctuations - design parameters previously reserved for larger aerodynamic or aero-acoustic wind tunnels. The aerodynamic design was achieved, in-part, by use of computational fluid dynamics and a purpose-built model wind tunnel.

Due to its high specific power density, immediate and lively throttle response, good efficiency and life cycles comparable to current powertrain concepts the hydrogen internal combustion engine (H2-ICE) will play a major role in future automotive propulsion systems. The new bi-fuel 12-cylinder hydrogen internal combustion engine for the 7 series is an important step in this direction. In this article engine design and the development of the engine functions of the new H2-12-cylinder will be shown in detail. In particular the engine operation strategy to achieve high efficiencies and very low tail pipe emissions will be presented. Finally potentials of the mono-fuel derivative will be discussed and an outlook for future engine concepts will be given.

The first part of the paper describes the brake system of the BMW 850i including brake actuation, brake split and ABS. ABS control philosophy and components are presented as well as performance date are shown. The BMW 850i will be available with two Automatic Stability Control systems ASC und ASC+T which are explained more in detail. Special attention is payed to the electronic and hydraulic interfacing of the different sub-systems required for ABS and ASC.

For the BMW V8 engine, a new LEV/EU3 emission concept has been developed by improvements to the previous engine management and secondary air supply and a complete new exhaust system. Beside the emission limits, also high engine output targets and high operating reliability were targeted. In addition the new exhaust system had to meet low cost targets. Based on these requirements an exhaust concept with separate pre catalyst and main catalyst was chosen. To reduce the heat mass and to optimize the pressure drop, 4.3mil/400cpsi thin wall ceramic substrates were used for the pre and main catalyst.

To meet LEV and EU Stage III emission requirements, it is necessary for new catalytic converters to be designed which exceed light-off temperature as quickly as possible. The technical solutions are secondary air injection, active heating systems such as the electrically heated catalytic converter, and the close coupled catalytic converter. Engine control functions are extensively used to heat the converter and will to play a significant role in the future. The concept of relocating the converter to a position close to the engine in an existing vehicle involves new conflicts. Examples include the space requirements, the thermal resistance of the catalytic coating and high temperature loads in the engine compartment.

The development of the S-designed metallic catalytic converter and the flexibility of its production paved the way for the first conical converter with continuous cell enlargement. This type of conical converter, installed upstream from a standard catalytic conversion system exerts a positive influence on flow distribution and converter efficiency, both during the cold start and under operating conditions. The study results outlined in the following text demonstrate the potential for increased catalytic effectiveness, taking the example of the close-coupled application.

BMW's concept for recycling old cars seeks to avoid shredder residues in the recycling process to the greatest possible extent. Any absolutely unavoidable, non-utilizable residues are to be suitable for disposal at domestic waste sites. An important feature of this recycling concept is the removal of operating fluids and dismantling of any components, parts and materials worthy of further use from old cars. This corporate policy, supported by legal standards calls for the automobile recycler to meet increasing demands in terms of facilities and equipment as internal processes. Proper fulfilment of these requirements is indeed a fundamental prerequisite for companies wishing to be accepted within the network of recycling plants. Like the production of vehicles, the subsequent utilisation and recycling of vehicles must be considered in the light of economic criteria.

The new BMW Aerodynamisches Versuchszentrum (AVZ) wind tunnel center includes a full-scale wind tunnel, "The BMW Windkanal" and an aerodynamic laboratory "The BMW AEROLAB." The AVZ facility incorporates numerous new technology features that provide design engineers with new tools for aerodynamic optimization of vehicles. The AVZ features a single-belt rolling road in the AEROLAB and a five-belt rolling road in the Windkanal for underbody aerodynamic simulation. Each of these rolling road types has distinct advantages, and BMW will leverage the advantages of each system. The AEROLAB features two overhead traverses that can be configured to study vehicle drafting, and both static and dynamic passing maneuvers. To accurately simulate "on-road" aerodynamic forces, a novel collector/flow stabilizer was developed that produces a very flat axial static pressure distribution. The flat static pressure distribution represents a significant improvement relative to other open jet wind tunnels.

The use of micro controllers in automotive systems renders the coordination of about 150 actors (70 electric motors, 15 magnetic valves and 50 relays). The resulting complexity of those systems as well as the requested zero defects demands time consuming testing. This work describes a method of performing test-scenarios, starting from a zero defect running specification, modeled by finite state machines. The test-scenarios are intended to determine whether a given system meets all specification requirements. First, a kind of structured modelling reactive automotive systems is deduced. Next, some important test selection methods, developed for the case the specification is given in the form of a finite state machine, are considered. Finally, a procedure and method for performing minimized complete test-scenarios for automotive systems are presented.

For the first time in volume production, supporting welded aluminum structures were used in the chassis area. Metal sheets, extruded sections, longitudinally seam welded pipes and castings were used as semi-finished products. Extensive strength tests, in cooperation with the Design Department and Production, resulted in sophisticated design solutions. In considering matters important to the customer, these solutions were substantiated through numerous examinations which are especially necessary for aluminum.