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Multicore processor are well established in classical and tablet personal computers for some year. Such processors use more then one central core for computation and allow to integrate more computational power with smaller costs. However more than 90% of all processors worldwide are not placed in classical IT but are empedded in bigger systems like in modern vehicles or airplanes. Such systems face a very high demand in terms of safety, security an reliability which hinders the use of multicores in such systems. The funded project ARAMiS faces these demands and has the goal to enable the usability of multicore systems in the domains automotive and avionics, as well as later also railway. ARAMiS is the basis for higher traffic safety, traffic efficiency and comfort.

Today, body vibration energy of passenger cars gets dissipated by linear working shock absorbers. A new approach substitutes the damper of a passenger car by a cardanic gimbaled flywheel mass. The constructive design leads to a rotary damper in which the vertical movement of the wheel carrier leads to revolution of the rotational axis of the flywheel. In this arrangement, the occurring precession moments are used to control damping moments and to store vibrational energy. Different damper characteristics are achieved by different induced precession. From almost zero torque output to high torque output, this damper has a huge spread. Next to the basic principal, in this paper an integration in the chassis, including a constructive proposal is shown. A conflict with high torque and high angular velocity leads to a special design. Moreover concepts to deal with all vehicle situations like yawing, rolling and pitching are shown.

Starting from the USA and followed by the European Union, legal requirements concerning “Tire Pressure Monitoring Systems” (TPMS) for passenger cars and light trucks will be introduced in China as well and therefore in the third of the three largest automobile markets worldwide. Changes of pressure dependent physical tire properties such as dynamic roll radius and a certain tire eigenfrequency, which are included in the ESC-wheel speed signals, indicates pressure loss in an indirect manner. Systems with corresponding working principles are called “indirect Tire Pressure Monitoring System” (iTPMS). Since the tire is a structural element with varying characteristics according to the design parameters, the roll radius and frequency behavior due to pressure loss is variable as well. As a consequence, tires have to be evaluated regarding there compatibility to iTPMS during the vehicle development process.

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.

Helmholtz-resonators are discussed in technical acoustics normally in conjunction with attenuation of sound, not with amplification or even production of sound. On the other hand everybody knows the sound produced by a bottle, when someone blows over the orifice. During the investigation of the sound produced in body gaps it was found that the underlying flow physics are closely related to the Helmholtz-resonator. But different from the typical Helmholtz-resonator generated noise – as for example the blown bottle or, from the automotive world, the sun roof buffeting – there is no fluid resonance involved in the process. For body gaps the random pressure fluctuation of the turbulent boundary layer is sufficient to excite the acoustic resonance in the cavity. The sound generation is characterized by a continuous rise in sound pressure level with increasing velocity, the rise is proportional to U with varying exponents.

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.

In open jet wind tunnels with high blockage ratios a sharp rise in drag is observed for models approaching the nozzle exit plane. The physical background for this rise in drag will be analyzed in the paper. Starting with a basic analysis of the dependencies of the effect on model and wind tunnel properties, the key parameters of the problem will be identified. It will be shown using a momentum balance and potential flow theory that interaction between model and nozzle exit can result in significant tunnel-induced gradients at the model position. In a second step, a CFD-based investigation is used to show the interaction between nozzle exit and a bluff body. The results cover the whole range between open jet and closed wall test section interaction. The model starts at a large distance from the nozzle, then moves towards the nozzle, enters the nozzle and is finally completely inside the nozzle.

The ever increasing use of electronics in modern vehicles has not stopped at comfort systems such as power seats and power windows. Every conventional system that requires operating force will eventually be replaced by a self-powered version. One such item is the electromechanical parking brake of the new Audi A8, offering a host of new features. Despite the many options for new functions, it is nevertheless important to keep the driver in mind. Being engineers, one tends to overlook that not all customers share our excitement for gadgets and overly complicated technical features.

A region with floor boundary-layer suction upstream of the vehicle to remove the oncoming boundary layer is often used in automotive wind tunnels. These suction systems inevitably change the empty-tunnel pressure gradient. In this paper, the empty-tunnel pressure gradient created by the use of boundary layer suction and its effect on measured drag are investigated. By using excess suction - more suction than necessary to remove the floor boundary layer – it was possible to show experimentally that the major part of the drag increase due to boundary layer suction is created by unintended gradient effects. Only a minor part of the drag increase is due to the increased flow velocities at the lower parts of the vehicle, or in other words, due to the improved ground simulation. A theoretical model, using the concept of horizontal buoyancy to predict the gradient effect, is proposed. The model is compared to the experimental results as well as to CFD calculations.

The potential of determining the change of injury severity in the accident event taking passive as well as active measures into account at the vehicle (integral systems) are at present limited to pedestrian protective systems. Therefore, an extension of the existing methods for the application with common integral systems (front protection, side protection, etc.) is suggested. Nowadays the effectiveness of passive safety systems is determined in crash tests with very high accident severities. However, approximately 90% of real-world accidents have a lower accident severity as the required crash tests. Thus, this paper will present a method calculating the effectiveness of such an integral system based on real-world accident data. For these reasons, this paper is presenting a method for a more valid prediction of injury severity. The German In-Depth Database GIDAS allows clustering the accident event in relevant car-to-car scenarios.

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.

Minimizing the lap time for a given race track is the main target in racecar development. In order to achieve the highest possible performance of the vehicle configuration the mutual interaction at the level of assemblies and components requires a balance between the advantages and disadvantages for each design decision. Especially the major shift in the focus of racecar powerunit development to high efficiency powertrains is driving a development of lean boosted and rightsized engines. In terms of dynamic engine behavior the time delay from requested to provided torque could influence the lap time performance. Therefore, solely maximizing the full load behavior objective is insufficient to achieve minimal lap time. By means of continuous predictive virtual methods throughout the whole development process, the influence on lap time by dynamic power lags, e.g. caused by the boost system, can be recognized efficiently even in the early concept phase.

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.

The present paper reveals the design concept as well as results of experimental investigations, which were conducted in the early design stage of the planned AUDI Aero-Acoustic Wind Tunnel. This low-noise open-jet facility, featuring a nozzle exit area of 11 m2 and a top speed of approximately 60 m/s, enables aerodynamic as well as acoustic testing of both, full-scale and model-scale ground vehicles. Ground simulation is provided by means of a moving-belt rig. The surrounding plenum is designed as a semi-anechoic chamber to simulate acoustic free-field conditions around the vehicle. Fan noise will be attenuated below the noise level of the open jet. The work reported herein, comprises 1/8-scale pilot-tunnel experiments of aerodynamic and acoustic configurations which were carried out at the University of Darmstadt.

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.

Cooling drag is the increase in the total drag due to the internal flow in the cooling system. Because of the high flow resistance in the heat exchanger the momentum of the fluid needed for engine cooling usually is dissipated nearly completely. The resulting drag penalty can be approximated by the so called ram drag. For ground vehicles the cooling drag is typically lower than this approximation due to positive interference of the cooling flow with the general flow around the vehicle. Different mechanisms for the positive interference have been described in the literature. Inlet interference as well as outlet interference can result in significant reduction of the share of the cooling drag. Positive outlet interference is obtained, when the remaining kinetic energy of the cooling flow contributes significant thrust to the overall momentum balance.

For the aerodynamic development of an aircraft the induced drag is an important quantity and it has a significant impact on the design of the wing. The induced drag corresponds to the power requirement of the wing to generate the necessary lift. In many cases this is the dominant source of drag for aircraft. In ground vehicle aerodynamics the concept of induced drag up to now has attracted much less attention. This is partly due to the fact, that vehicle aerodynamicists usually optimize the vehicles to generate little or no lift. The second reason is that it is much more difficult for a ground vehicle to separate the total drag into the different contributions. During wind tunnel tests of vehicles with and without ground simulation some astonishing results were found, especially when comparing results for different rear end shapes.

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.

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.