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With the ever increasing amount of available software processing resources in a vehicle, more and more high-level algorithms are emerging to improve the existing systems in a car. Often these algorithms only need a platform with a bus connection and some resources such as processing power and memory space. These functions are predestined to be integrated into existing systems that have free resources. This paper will examine the role of time protection in these multi-algorithm systems and describe what timing protection means and why it is required. The processing time will be partitioned to the different processing levels like interrupts, services and tasks. The problems of timing protection will be illustrated as well as its limitations. The conflict between real-time requirements and timing protection will be shown. Finally Autosar will be examined with focus on timing protection and applicability in actual development projects.

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.

Audi's new full scale aeroacoustic wind tunnel is under full operation now. The new facility is designed for full scale automotive testing of aerodynamics and aeroacoustics for vehicles up to 3 m2 frontal area at wind speeds up to 300 kph. The highlights are the unique ground simulation system with boundary layer suction and a 5-belt-system, and the extremely low background noise of only 60 dB(A) at 160 kph. First the background of the project is illustrated and the need for the special features of the tunnel is deduced form the industrial requirements. Then an overview of the facility design is given with a detailed description of the key technical components. The calibration of the self-correcting test section will be discussed and the physical background for it will be examined more closely. For the calibrated wind tunnel the results of two correlation tests including open jet as well as closed wall wind tunnels show a reasonable conformity.

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.

In the context of the ARAMiS project, AUDI AG contributed the development of a multi-core demonstrator based on car functions already in production. For this demonstrator, these legacy car functions were ported from single-core platforms to a multi-core platform to gain real world close-to-production experience while utilizing the new technology. For complex functions with high demands for computational resources, it may be necessary to distribute computation over several cores. In this context, we investigated the parallelization of a legacy sequential AUTOSAR function. A main contribution of this work is an analysis of mechanisms provided by AUTOSAR, their limitations and, possible remedy. This paper will point out observations and experiences during the development of this demonstrator and show practical solutions for parallelization in an AUTOSAR environment.

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.

The reference pressures are determined in automotive wind tunnels by measurement of pressures and pressure differences at upstream positions along the wind tunnel nozzle. For closed wall wind tunnels usually the so called nozzle method is used, where the volume flux is calculated from a pressure difference measured at the nozzle contour and a calibration factor determined in the empty test section. For open jet wind tunnels a choice is available between nozzle and plenum method. For the plenum method the reference static pressure is taken from the plenum chamber and the dynamic pressure also refers to the plenum conditions. The static reference pressure in closed wall tunnels is calculated by subtracting the dynamic pressure from the total pressure in the settling chamber. In this paper, the definitions and the differences between the two methods are discussed in detail.

Developing automotive chassis applications is becoming increasingly complex due to cross-functional system interactions and the inherent safety critical nature of the systems involved. One consequence is the need for a rapid prototyping platform, targeted and tailored to meet the specific needs of the chassis domain. This paper describes an example of such an architecture for a chassis rapid prototyping system incorporating several Infineon TriCore embedded microcontrollers and Emulation Devices (ED), networked together by the Micro Link Interfaces (MLI). It also discusses how using such a development platform can lead to a significant reduction in the overall development time of a production intent chassis system.

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.

With the introduction of the ISO26262 automotive safety standard there is a burden of proof to show that the processing elements in embedded microcontroller hardware are capable of supporting a certain diagnostic coverage level, depending on the required Automotive Safety Integrity Level (ASIL). The current mechanisms used to provide actual metrics of the Built-in Self Tests (BIST) and Lock Step comparators use Register Transfer Level (RTL) simulations of the internal processing elements which force faults into individual nodes of the design and collect diagnostic coverage results. Although this mechanism is robust, it can only be performed by semiconductor suppliers and is costly. This paper describes a new solution whereby the microcontroller is synthesized into a large Field Programmable Gate Array (FPGA) with a test controller on the outside.

A main challenge when developing next generation architectures for automated driving ECUs is to guarantee reliable functionality. Today’s fail safe systems will not be able to handle electronic failures due to the missing “mechanical” fallback or the intervening driver. This means, fail operational based on redundancy is an essential part for improving the functional safety, especially in safety-related braking and steering systems. The 2-out-of-2 Diagnostic Fail Safe (2oo2DFS) system is a promising approach to realize redundancy with manageable costs. In this contribution, we evaluate the reliability of this concept for a symmetric and an asymmetric Electronic Power Steering (EPS) ECU. For this, we use a Markov chain model as a typical method for analyzing the reliability and Mean Time To Failure (MTTF) in majority redundancy approaches. As a basis, the failure rates of the used components and the microcontroller are considered.

Advanced safety features and new services in connected cars depend on the security of the underlying vehicle functions. Due to the interconnection with the outside world and as a result of being an embedded system a modern vehicle is exposed to both, malicious activities as faced by traditional IT world systems as well as physical attacks. This introduces the need for utilizing hardware-assisted security measures to prevent both kinds of attacks. In this paper we present a survey of the different classes of hardware security devices and depict their different functional range and application. We demonstrate the feasibility of our approach by conducting a case study on an exemplary implementation of a function-on-demand use case. In particular, our example outlines how to apply the different hardware security approaches in practice to address real-world security topics. We conclude with an assessment of today’s hardware security devices.

The German funded project ARAMiS included work on several demonstrators one of which was a multicore approach on large scale software integration (LSSI) for the automotive domain. Here BMW and Audi intentionally implemented two different integration platforms to gain both experience and real life data on a Hypervisor based concept on one side as well as using only native AUTOSAR-based methods on the other side for later comparison. The idea was to obtain figures on the added overhead both for multicore as well as safety, based on practical work and close-to-production implementations. During implementation and evaluation on one hand there were a lot of valuable lessons learned about multicore in conjunction with safety. On the other hand valuable information was gathered to make it finally possible to set up a cost model for estimation of potential overhead generated by different integration approaches for safety related software functions.

Electronic Control Units of safety critical systems require constant monitoring of the hardware to be able to bring the system to a safe state if any hardware defects or malfunctions are detected. This monitoring includes memory checking, peripheral checking as well as checking the main processor core. However, checking the processor core is difficult because it cannot be guaranteed that the error will be properly detected if the monitor function is running on a processing system which is malfunctioning. To circumvent this issue, several previously presented monitoring concepts (e.g. SAE#2006-01-0840) employ a second external microprocessor to communicate with the main processor to check its integrity. This paper will present a concept which maps the functions of the external monitoring unit into an internal second processing core which are frequently available on modern, 32bit, monolithic, dual-core microcontrollers.

Hydromechanical sheet forming (AHU®) is an innovative production process with interesting applications, possibilities and potential for the cost-effective manufacture of automobile body parts, particularly with regard to the use of new and improved steels. The targeted, component-specific use of hydro-mechanical sheet forming in automobile construction promises to deliver outstanding results from both a technological and economic point of view.

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.

This paper proposes end-to-end protection mechanisms to be added to a generic FlexRay network in order to achieve fault detection and integrity levels sufficient for a SIL3 fail safe communication system. The mechanisms are derived from the random hardware failure modes to be considered for communication controllers according to IEC 61508. Mechanisms provided by the FlexRay protocol are pointed out. Additional features necessary to fulfil the requirements are discussed. It is shown how to calculate the failure rate probabilities of the CRC used as a safety code with respect to EN 50159.

More and more high-level algorithms are emerging to improve the existing systems in a car. Often these algorithms only need a platform with a bus connection and some resources such as CPU time and memory space. These functions can easily be integrated into existing systems that have free resources. This paper describes some encapsulation techniques and mechanisms that can be used in the automotive domain. The discussion also takes into account the additional resources consumed on the microcontroller to meet these requirements and by the software to implement the encapsulation mechanisms. Overviews of some general concepts of software-architectures that provide encapsulation are also shown.

GTL (Gas-To-Liquid) fuel is well known to improve tailpipe emissions when fuelling a conventional diesel vehicle, that is, one optimized to conventional fuel. This investigation assesses the additional potential for GTL fuel in a GTL-dedicated vehicle. This potential for GTL fuel was quantified in an EU 4 6-cylinder serial production engine. In the first stage, a comparison of engine performance was made of GTL fuel against conventional diesel, using identical engine calibrations. Next, adaptations enabled the full potential of GTL fuel within a dedicated calibration to be assessed. For this stage, two optimization goals were investigated: - Minimization of NOx emissions and - Minimization of fuel consumption. For each optimization the boundary condition was that emissions should be within the EU5 level. An additional constraint on the latter strategy required noise levels to remain within the baseline reference.

The development of highly automated driving functions (AD) recently rises the demand for so called Fail-Operational systems for native driving functions like steering and braking of vehicles. Fail-Operational systems shall guarantee the availability of driving functions even in presence of failures. This can also mean a degradation of system performance or limiting a system’s remaining operating period. In either case, the goal is independency from a human driver as a permanently situation-aware safety fallback solution to provide a certain level of autonomy. In parallel, the connectivity of modern vehicles is increasing rapidly and especially in vehicles with highly automated functions, there is a high demand for connected functions, Infotainment (web conference, Internet, Shopping) and Entertainment (Streaming, Gaming) to entertain the passengers, who should no longer occupied with driving tasks.