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Ethernet is the hottest candidate for future in-car communication architecture, promising much higher bandwidth, flexibility and reduced costs. In the coming years, Ethernet will likely evolve from a separate communication medium for special applications like surround-view cameras and infotainment to a central communication infrastructure as a backbone technology. To make this transition, many difficult design decisions have to be made in order to make the technology suitable for the stricter time and safety requirements of todays and future cars. There are a lot of potential real-time effects that must be taken into account. To guide these design decisions, it is necessary to analyze the various architecture concepts with respect to load, performance and real-time capabilities. In this paper, we present different design space axes of Ethernet and propose a methodology of assessing and comparing them.

The integration of mixed-criticality software according to safety standards like ISO 26262 generates new, parasitic mutual effects within the involved software architectures. In this situation, established schedule design patterns like RMS fail to deliver both efficiency and safety, in particular the freedom of interference. In today's practice of building a schedule, certain such measures to fulfill these safety requirements can conflict with efficiency requirements. The target of this paper is to present a sound approach of how to solve such requirement conflicts and to build up schedules that are safe and also efficient. We present a general early-stage procedure to build safe, certifiable, and efficient schedules. The procedure is based on the established design patterns and adds guidelines on how to exploit additional options in both schedule design and software partitioning. This procedure was validated against typical real-world systems and one example is presented.

Today's automotive software integration is a static process. Hardware and software form a fixed package and thus hinder the integration of new electric and electronic features once the specification has been completed. Usually software components assigned to an ECU cannot be easily transferred to other devices after they have been deployed. The main reasons are high system configuration and integration complexity, although shifting functions from one to another ECU is a feature which is generally supported by AUTOSAR. The concept of a Virtual Functional Bus allows a strict separation between applications and infrastructure and avoids source code modifications. But still further tooling is needed to reconfigure the AUTOSAR Basic Software (BSW). Other challenges for AUTOSAR are mixed integrity, versioning and multi-core support. The upcoming BMW E/E-domain oriented architecture will require all these features to be scalable across all vehicle model ranges.

The automakers that comprise MOST® describe the reasons for this decision. First, they present the automobile industry's needs relative to multimedia networks in vehicles. Then, they present the different aspects of the MOST® technology. Multimedia networks are used in the electronics market, but they do not meet the technical and industrial constraints of the automobile electronics, which is why six automakers are working on most technology under the aegis of ""Most Cooperation.'' The transmission rate is a decisive aspect in the selection of a multimedia network. The rate of sound and video applications require fiber optics. The multimedia network rate must be adequate for a vehicle equipped with the maximum number of options, but the maximum rate is limited by the number of passengers.

The lightweight construction strategies that are demanded by the automobile industry are being employed more and more. These strategies lead to the increasing importance of the forming method and types of materials used. Especially forming technologies based on liquid media have the potential to meet these demands. These forming technologies make it possible to produce parts that have both, more complex geometries and optimized characteristics. This forming technology constitutes an intelligent process management including the significant materials parameters and behavior, the simulation and some new developments especially for the optimization of the quality and the cycle time. Hydromechanical sheet forming (AHU®) is an alternative production (forming) process, with very interesting results and developments for the manufacture of specific automobile components.

Developers of safety-critical real-time systems have to ensure that their systems react within given time bounds. Ideally, the system is designed to provide sufficient computing power and network bandwidth, is cost efficient and provides the necessary safety level. To achieve this goal, three challenges have to be addressed. First, it must be possible to account for timing during early development stages in the architecture exploration phase. Second, during software development, timing behavior and the effects of software changes on timing must be observable. Third, there must be a technology for formally verifying the final timing behavior for industry-size applications. In this article we present a comprehensive methodology for dealing with timing which addresses all three issues based on state-of-the-art commercial tools.

ISO 26262 is the actual standard for Functional Safety of automotive E/E (Electric/Electronic) systems. One of the challenges in the application of the standard is the distribution of safety related activities among the participants in the supply chain. In this paper, the concept of a Safety Element out of Context (SEooC) development will be analyzed showing its current problematic aspects and difficulties in implementing such an approach in a concrete typical automotive development flow with different participants (e.g. from OEM, tier 1 to semiconductor supplier) in the supply chain. The discussed aspects focus on the functional safety requirements of generic hardware and software development across the supply chain where the final integration of the developed element is not known at design time and therefore an assumption based mechanism shall be used.

New power train concepts in the automobile industry will decisively change the familiar car acoustics. Secondary acoustic noise sources will be unmasked and dominate the driver's sound experience. The most important secondary noise source is the air conditioning (AC) system. Before a favorable AC sound can actively be designed, it is necessary to identify the acoustic noise sources and find means to influence them. This paper focuses on the AC outlet module which is, apart from the control unit, the only part visible to the customer. Typical acoustic spectra of flowed-through outlets show a characteristic tonality at about 3000 Hz. The knowledge of its aeroacoustic source mechanisms, the inherent implications for the customer and corrective measures especially in automobile surroundings has been limited so far. To analyze this phenomenon in detail, a simplified model outlet that shows the basic aeroacoustic behavior of a series production outlet was constructed and investigated.

For a long time, tools and methods for automotive E/E design were mostly in the domain of academic researches only. Recently, OEMs have started adopting selected contributions, because (very soon) it will become quite costly NOT to apply them. The first step is establishing centralized data storage for all design data. At present, selecting appropriate abstraction levels and design methods that get fed by and feed the data is the task at hand. In this paper, we summarize recent progress in this selection process with a focus on performance; which is a key aspect for architecture generation. Our contribution provides incremental progress from both ends of the mentioned gap (requirements vs. architecture vs. implementation) towards one another. The presentation is created around the IMES project [21] considering centralized data storage. However, the overall approach is based on established standards and common design patterns as much as possible.

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.

Handling characteristics, ride comfort and active safety are customer relevant attributes of modern premium vehicles. Electronic control units offer new possibilities to optimize vehicle performance with respect to these goals. The integration of multiple control systems, each with its own focus, leads to a high complexity. BMW and ITK Engineering have created a tool to tackle this challenge. A simulation environment to cover all development stages has been developed. Various levels of complexity are addressed by a scalable simulation model and functionality, which grows step-by-step with increasing requirements. The simulation environment ensures the coherence of the vehicle data and simulation method for development of the electronic systems. The article describes both the process of the electronic control unit (ECU) development and positive impact of an integrated tool on the entire vehicle development process.

The production of the BMW ALPINA B12 5.7 with Switch-Tronic transmission provides the markets of Europe and Japan with an exclusive, luxury-orientated, high performance limited series limousine. This is the first vehicle worldwide to be fitted with the progressive exhaust gas aftertreatment technology known as the Electrically Heated Catalyst (EHC), in which the effectiveness of the power utilized is increased significantly by an alternating heating process for both catalytic converters. Only since this achievement has the implementation of the EHC been viable without extensive modification to the battery and alternator. With this exhaust gas aftertreatment concept, the emissions of this high performance vehicle will fall to less than half the maximum permissible for compliance with 1996 emission standards.

A lot of very valuable information has already been gained in the process of dismantling, assorting and reconditioning plastic parts on old cars, in reconditioning defective plastic parts from workshops, and in the use of reject parts from production. This know-how is now applied primarily to increase the use of recycled plastics and to optimise the composition and design of future plastic components in the interest of recycling, since further development in these areas is essential in order to establish economically stable material cycles functioning properly in the long term. The present paper describes the most important criteria through which the materials and designs chosen affect the processes and principles of recycling in the case of plastic parts and components.

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.

More electronic vehicle functions lead to an exponentially growing degree of software integration in automotive ECUs. We are seeing an increasing number of ECUs with mixed criticality software. ISO26262 describes different safety requirements, including freedom from interference and absence from error propagation for the software. These requirements mandate particular attention for mixed-criticality ECUs. In this paper we investigate the ability to guarantee that these safety requirements will be fulfilled by using established (deadline monitoring) and new error detection mechanisms (execution time monitoring). We also show how these methods can be used to build up safe and efficient schedules for today's and future automotive embedded real time systems with mixed criticality software.

The increased pressure for power, space, and cost reduction in automotive applications together with the availability of high performance, automotive qualified multicore microcontrollers has lead to the ability to engineer Domain Controller ECUs that can host several separate applications in parallel. The standard automotive constraints however still apply, such as use of AUTOSAR operating system, support for legacy code, hosting OEM supplied code and the ability to determine warranty issues and responsibilities between a group of Tier 1 and Tier 2 vendors who all provide Intellectual Property to the final production ECU. Requirements for safety relevant applications add even more complexity, which in most current approaches demand a reconfiguration of all basic software layers and a major effort to redesign parts of the application code to enable co-existence on the same hardware platform. This paper outlines the conflicting requirements of hosting multiple applications.

Multicore-based ECUs are increasingly used in embedded automotive software systems to allow more demanding automotive applications at moderate cost and energy consumption. Using a high number of parallel processors together with a high number of executed software components results in a practically unmanageable number of deployment alternatives to choose from. However correct deployment is one important step for reaching timing goals and acceptable latency, both also a must to reach safety goals of safety-relevant automotive applications. In this paper we focus at reducing the complexity of deployment decisions during the phases of allocation and scheduling. We tackle this complexity of deployment decisions by a mixed constructive and analytic approach.

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 increasing complexity of automotive functions which are necessary for improved driving assistance systems and automated driving require a change of common vehicle architectures. This includes new concepts for E/E architectures such as a domain-oriented vehicle network based on powerful Domain Control Units (DCUs). These highly integrated controllers consolidate several applications on different safety levels on the same ECU. Hence, the functions depend on a strictly separated and isolated implementation to guarantee a correct behavior. This requires middleware layers which guarantee task isolation and Quality of Service (QoS) communication have to provide several new features, depending on the domain the corresponding control unit is used for. In a first step we identify requirements for a middleware in automotive DCUs. Our goal is to reuse legacy AUTOSAR based code in a multicore domain controller.

Systems and network integration is a major challenge, and systematic analysis of the complex dynamic timing effects becomes key to building reliable systems. Very often, however, systematic analysis techniques are (considered) too restrictive with respect to established design practice. In this paper we present lessons learned from real-world case studies, in which OEMs have used the new SymTA/S scheduling analysis technology to evaluate different network choices with minimum effort. Thanks to its flexibility and supplier independence, SymTA/S can be applied in non-ideal situations, where other, more restricted technologies are inherently limited. Finally, we put the technology into relation with ongoing standardization activities.