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With the huge improvements made during the last years in the area of integrated safety systems, they are one of the main contributors to the massively rising complexity within automotive systems. However, this enormous complexity stimulates the demand for methodologies supporting the efficient development of such systems, both in terms of cost and development time. Within this work, we propose a co-simulation-based approach for the validation of integrated safety systems. Based on data measurements gained from a test bed, models for the sensors and the distributed safety system are established. They are integrated into a co-simulation environment containing models of the ambience, driving dynamics, and the crash-behavior of the vehicle. Hence, the complete heterogeneous system including all relevant effects and dependencies is modeled within the co-simulation.

Over the past 30 years, the computer-aided engineering (CAE) tools have been applied extensively in the automotive industry. In order to accelerate time-to-market while coping with legal limits that have become increasingly restrictive over the last decades, CAE has become an indispensable tool covering all major fields in a modern automotive product design process. However, when tackling complex real-life engineering problems, the computational models might become rather involved and thus less efficient. Therefore, the overall trend in the automotive industry is currently heading towards combined approaches, which allow the best of the both worlds, namely the experimental measurement and numerical simulation, to be merged into one integrated scheme. In this paper, the so-called patch transfer function (PTF) approach is adopted to solve coupled vibro-acoustic problems. In the PTF scheme, the interfaces between fluid and structure are discretised in terms of patches.

The analysis of the acoustic behavior of flow fields has gained importance in recent years, especially in the automotive industry. The comfort of the driver is heavily influenced by the noise levels and characteristics, especially during long distance drives. Simulation tools can help to analyze the acoustic properties of a car at an early stage of the development process. This work focuses on the low-frequency sound effects, which can be a significant noise component under certain operating conditions. As a first step in the fluid-structure interaction workflow, the flow around a series-production vehicle is simulated, including passenger cabin and underhood flow. The complexity of this model poses extensive demands on the simulation software, concerning meshing, turbulence modeling and level of parallelism. We conducted a transient simulation of the compressible fluid flow, using a hybrid RANS/LES approach.

Comfort and well-being have always been connected with a flawless interior acoustic, free of any background noise or BSR, (buzz, squeak and rattle). BSR noises dominate the interior acoustic and represent one of the main sources for discomfort often causing considerable warranty costs. Traditionally BSR issues have been identified and rectified through extensive hardware testing, which by its nature intensifies toward the end of the car development process. In the following paper the integration of a virtual BSR validation technique in a modern development process by the use of appropriate CAE methods is presented. The goal is to shift, in compliance with the front loading concept, the development activities into the early phase. The approach is illustrated through the example of an instrument panel, from the early concept draft for single components to an assessment of the complete assembly.

Virtual testing has grown to be an efficient tool in vehicle passive safety design. Most simulations currently are deterministic. Since the responses observed in real-life and standardized tests are greatly affected by scatter, a stochastic approach should be adopted in order to improve the predictability of the numerical responses with respect to the experimental data. In addition, an objective judgement of the performance of numerical models with respect to experimental data is necessary in order to improve the reliability of virtual testing. In the European VITES & ADVANCE project the software tool Adviser was developed in order to fulfil these two requirements. With Adviser, stochastic simulations can be performed and the quality of the numerical responses with respect to the experimental can be objectively rated using pre-defined and user-defined objective correlation criteria. The software Adviser was used to develop a stochastic HybridIII 50th% Madymo numerical model.

Reductions of hardware costs as well as implementations of new innovative functions are the main drivers of today's automotive electronics. Indeed more and more resources are spent on adapting existing solutions to different environments. At the same time, due to the increasing number of networked components, a level of complexity has been reached which is difficult to handle using traditional development processes. The automotive industry addresses this problem through a paradigm shift from a hardware-, component-driven to a requirement- and function-driven development process, and a stringent standardization of infrastructure elements. One central standardization initiative is the AUTomotive Open System ARchitecture (AUTOSAR). AUTOSAR was founded in 2003 by major OEMs and Tier1 suppliers and now includes a large number of automotive, electronics, semiconductor, hard- and software companies.

Advanced Driver Assistance systems support the driver in his driving tasks. They can be designed to enhance the driver's performance and/or to take over unpleasant tasks from the driver. An important optimization goal is to maintain the driver's activation at a moderate level, avoiding both stress and boredom. Functions requiring a situational interpretation based on the vehicle environment are associated with lower performance reliability than typical stability control systems. Thus, driver assistance systems are designed assuming that drivers will monitor the assistance function while maintaining full control over the vehicle, including the opportunity to override as required. Advanced driver assistance systems have a substantial potential to increase active safety performance of the vehicle, i.e., to mitigate or avoid traffic accidents.

Advanced material technologies play a key role in automotive engineering. The main objective of the development of advanced material technologies for automotive applications is to promote the desired properties of a vehicle. It is characteristic of most materials in modern cars that they have been developed especially for automotive requirements. Requirements are not only set by the customer who expects the maximum in performance, comfort, reliability, and safety from a modern car. Existing legal regulations also have to be met, e.g., in the areas of environmental compatibility, resource preservation, and minimization of emissions. To achieve goals like weight reduction or increased engine performance permanent material developments are essential. In this paper, numerous examples chosen from body, suspension, and powertrain components show clearly how low weight technologies, better comfort, and high level of recyclability can be achieved by advanced material solutions.

The importance of the automotive interior as a characteristic feature in the competition for the goodwill of the customer has increased significantly in recent years. Whilst there are established, more or less efficient CAE processes for the solution of problems in the areas of occupant safety and service strength, until now the implementation of CAE in themes such as dimensional stability, warpage and corrugation1 of plastic parts has been little investigated. The developmental support in this field is predominantly carried out by means of hardware tests. Real plastic components alter their form as a result of internal forces often during the first weeks following production. The process, known as “creep”, can continue over an extended period of time and is exacerbated by high ambient temperatures and additional external loads stemming from installation and post assembly position.

This article focuses on model based development of electronic control units (ECUs) in the automotive domain. The use of model-based approaches solves requirements for the fast-growing integration of formerly isolated logical functions in complex distributed networks of heavily interacting ECUs. One fundamental property of such an approach is the existence of an adequate modeling notation tailored to the specific needs of the application domain together with a precise definition of its syntax and its semantics. However, although these constituents are necessary, they are not sufficient for guaranteeing an efficient development process of ECU networks. In addition, methodical support which guides the application of the modeling notation must be an integral part of a model-based approach.

BMW can look back on 20 years of research activities on hydrogen propulsion systems. Hydrogen fuel is the only means of offering pure driving pleasure on the basis of a sustainable energy loop. As the hydrogen era is still quite a while away the BMW Energy Strategy „Via Natural Gas to Hydrogen” has been developed. The first step was to build series-production compressed natural gas (CNG) cars back in 1995. By switching to liquefied natural gas (LNG) not only is the cruising range tripled but technologically the final stepping-stone is reached in preparing the way for liquefied hydrogen. BMW's automotive and drive technology for hydrogen is now available and ready to move out of the laboratory on to the road. At Munich Airport a BMW „Clean Energy” car is already providing shuttle services. Its fuel is supplied by the world's first public filling station for liquefied hydrogen.

Sport Activity Vehicle (SAV) share a growing market of an entirely new class of vehicles. Outstanding comfort in traditional on-road and also off-road terrain combined with leading edge technology are basic features of this concept. But in addition to that, the SAV has to offer the same overall safety features, expected by e.g. a luxury-segment sedan. A way to ensure the BMW X5 becoming one of the safest cars was the consequent use of simulation techniques in passive safety development. This paper deals with introduction of a CAE driven development process for passive safety in the BMW X5 project, focusing on examples in front and side impact.

A comprehensive experimental study was conducted to investigate human movements when entering a vehicle. The primary goal of this study was to understand the influence of environmental changes on entry motions selected by a driver to enter a vehicle. The adjustable hardware setup “VEMO” (Variable Entry Mockup) was used for the experiments. With VEMO it is possible to simulate different types and classes of vehicle configurations. Around 30 test persons of different anthropometry participated in the experiments. The visual measurement system VICON was used for motion capturing, motion data cleaning and biomechanical analysis. The results corroborate the theory of leading body parts (LBPs) i.e. body parts that control targeted movement of the entire body. It could be demonstrated how motion patterns of LBPs, including spatial and dynamic characteristics such as orientation and velocity, respond to modifications of the geometrical environment.

As the popularity of vehicle navigation systems rises, incorporating Real Time Traffic Information (RTTI) has been shown to enhance the systems' value by helping drivers avoid traffic delays. As an innovative premium automaker, BMW has developed a testing process to acquire and analyze RTTI data in order to ensure delivery of a high quality service and to enhance the customer experience compared to audible broadcast services. With a methodology to obtain valid and repeatable RTTI data quality measurements, BMW and its service partner, Clear Channel's Total Traffic Network (TTN), can improve its offered service over time, implement corrective measures when appropriate, and confidently ensure the service meets its premium objectives. BMW has partnered with TTN and SoftSolutions GmbH to implement a traffic data quality process and software tools.

During early phases of interior car layout a lot of different aspects have to be considered like crashworthiness, regulations, philosophy of the company etc.. Ergonomic aspects do not always play the most important role in these cases. Since aspects of comfort in cars are getting more and more important in nowadays these aspects should be taken into account very early in the interior car layout process. This paper shows a way to design the interior layout of a car from scratch for a good postural comfort for all anthropometries with the aid of a digital human model (RAMSIS). The novelty of this approach is to use the digital human model to design the interior and not to verify or correct an existing one.

Classical decentralized architectures based on large networks of microprocessor-based Electronic Control Units (ECU), namely those used in self-driving cars and other highly-automated applications used in the automotive industry, are becoming more and more complex. These new, high computational power demand applications are constrained by limits on energy consumption, weight, and size of the embedded components. The adoption of new embedded centralized electrical/electronic (E/E) architectures based on dynamically reconfigurable hardware represents a new possibility to tackle these challenges. However, they also raise concerns and questions about their safety. Hence, an appropriate evaluation must be performed to guarantee that safety requirements resulting from an Automotive Safety Integrity Level (ASIL) according to the standard ISO 26262 are met. In this paper, a methodology for the evaluation of dynamically reconfigurable systems based on centralized architectures is presented.

The BMW Group is the first car manufacturer introducing FlexRay in series projects. Start of production is September 2006, where a pilot application is implemented in the chassis domain of the new BMW X5. In 2008 FlexRay will form a substantial part of the overall electronics architecture in form of a FlexRay network connecting multiple ECUs implementing chassis, powertrain, and driver assistance applications.

Evaluation of safety benefits is an essential task during design and development of pedestrian protection systems. Comparative evaluation of different safety concepts is facilitated by a common metric taking into account the expected human benefits. Translation of physical characteristics of a collision, such as impact speed, into human benefits requires reliable and preferably evidence-based injury models. To this end, the dependence of injury severity of body regions on explanatory factors is quantified here using the US Pedestrian Crash Data Study (PCDS) for pedestrians in frontal vehicle collisions. The explanatory and causal factors include vehicle component characteristics, physiological and biomechanical variables, and crash parameters. Severe to serious injuries most often involve the head, thorax and lower extremities.

This paper is supposed to address the BMW approach to the challenge of integrating chassis control systems and it highlights the major issues that have to be addressed. It points out possible solutions for scalable functional and hardware configurations for variable chassis control system combinations. A short outlook is given at possible functional benefits of an integrated structure. Finally, aspects such as components costs (e. g. for sensors and ECUs) as well as reactions on system failures and degradability have to be looked at.

Being able to integrate consumer electronics (CE) devices into the automobile is an increasingly important goal. In this paper, we focus on the HMI (human machine interaction) aspects of consumer electronics in the car. We describe the requirements concerning HMI integration of consumer electronics and offer several possible solutions. One of the requirements is minimal driver distraction. A desired property in this context concerns the mental model that the user builds of the service that is to be operated: ideally, this model (i.e., appearance and interaction logic) need not change when integrating the service into the automobile, even though the operating elements differ considerably (e.g., touch screen vs. iDrive commander). A further requirement is posed by the dynamic nature of CE services: often, they are not known at design/deploy time of the HMI software of the automobile.