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Distributed Computing systems consist of several processors that interact and cooperate with each other by message passing. These distributed systems provide many attractive features such as fault tolerance, resource sharing, high reliability and high throughput. These features make distributed systems good candidates for many real time applications such as aircraft, space crafts and automotive control. Car Industry is striving to provide reliable and cost effective Computing systems for their automobiles. As the number of processors increases in a vehicle, the demand increases to provide a reliable Computing system for the automotive. Therefore, it is important to develop specialized distributed Computing systems for this type of applications taking into consideration reliability as well as cost of the system. In this paper, a distributed Computing system architecture has been proposed for automotive applications.

In the automotive industry, in order to characterize and evaluate damping treatments, it is a common practice to employ Oberst bar tests as specified by ASTM E756 and SAE J1637. The ASTM standard provides equations for sandwiched Oberst bars. These equations allow engineers to extract the properties of the visco-elastic core. For certain type of automotive constrained-layer damping treatments, such as the Aluminum Foilback, it is often convenient and desirable to prepare the Oberst bar samples with production-intent configuration. Unfortunately, these configurations are often asymmetric. Therefore, the composite Oberst bar data cannot be post-processed by employing the ASTM equations. In this study, the ASTM equations for sandwiched bars are modified to accommodate for asymmetric Oberst bar configurations. The finite element method is used to validate the derived equations by performing a “Virtual Oberst Bar test.”

Automotive electronics and software is getting complex day by day. More and more features and functions are offered and supported by software in place of hardware. Communication is carried out on the CAN bus instead of hard wired circuits. This architectural transition facilitates lots of flexibility, agility and economy in development. However, it introduces risk of unexpected failures due to insufficient testing and million of possible combinations, which can be created by users during the life time of a product. Model based development supports an effective way of handling these complexities during simulation and also provide oracle for its validation. Based on priorities and type of applications, test vectors can be auto generated and can be used for formal verification of the models. These auto-generated test vectors are valuable assets in testing and can be effectively reused for target hardware (ECU) verification.

In automotive testing, a chassis dynamometer is typically used, during cell testing, to evaluate vehicle performance by simulating actual driving conditions. The use of indoor cell testing has the advantage of running controlled tests where the cell temperature and humidity and solar loads can be well controlled. Driving conditions such as vehicle speed, wind speed and grade can be also controlled. Thus, repeated tests can be conducted with minimum test variations. The tractive effort required at the wheels of a vehicle for a given set of operating parameters is determined by taking into account a set of variables which affect vehicle performance. The forces considered in determination of the tractive effort include the constant friction force, variable friction force due to mechanical and tire friction, forces due to inertia and forces due to aerodynamic and wind effects. In addition, forces due to gravity are considered when road grades are simulated.

Automotive electronics can be divided into subsystems according to their functions and physical locations Employing this concept, a hierarchical architecture of automotive electronics may be evolved In this paper a hierarchical fault tolerant distributed processing system has been introduced The system consists of a central controller (CC), m subsystems, a main bus and a shared memory module Each subsystem consists of n processors, one smart sensor group and one smart actuator group The central controller maintains the performance history of every processor in system In case of a processor's failure, the CC assigns the tasks of the faulty processor to another processor within the same subsystem Reliability, which is the probability of a correctly working system for an interval of time [t-t0], has been evaluated An algorithmic approach based on the truth table method has been developed for evaluating the reliability of the proposed hierarchical architecture A comparison of the reliability calculation has been done between the proposed architecture and a system without fault tolerance capability The results show that the proposed architecture provides better reliability

Vehicles are becoming part of the Internet, either as a terminal in a mobile network, as a network node or as a moving sensor (providing environmental, car status or video information). Interest of vehicles' passengers in location-based information is steadily growing. Moreover drivers and passengers may like to receive information about traffic jams or accidents in their vicinity, or chat with other vehicle's passengers. Enabling communication among automobile nodes (cars) is not a straightforward task. Such nodes form an extremely dynamic ad hoc network, and this presents some technical challenges. One essential characteristic of such networks is that the available services are in principle unknown to a node. A Dynamic Discovery Service (DDS) protocol to discover nodes is needed.

For a vehicle or repairable system, incidents (conditions) are neither necessarily independent nor identically distributed. Therefore, traditional statistical distributions like Weibull, Normal, etc, are no longer valid to estimate reliability. The Non-homogeneous Poisson process (NHPP) model can be used to predict reliability and warranty of the field product. It can also measure the reliability improvement during the development cycle. The NHPP model is discussed in this paper. In applying a NHHP model to reliability data on a repairable system, one may have few or no failures. This paper presents the I/100 and reliability derivations when the parameter β in the ROCOF function is assumed to have a known value.

This paper describes the performance improvement and cost savings achieved by the Stamping Technology Department at DaimlerChrysler Corporation (Chrysler group), in migrating from Unix workstations with RISC technology to Linux PCs with Intel Pentium technology. Performance comparisons of various engineering applications running on these two system configurations are analyzed. The major aspects such as hardware configuration, operating system, software availability, compatibility, reliability, accuracy and consistency of simulation results are discussed. The improvement in computing speed and deviations in simulation results between MPP LS-Dyna and SMP LS-Dyna are presented.

Most products are designed to operate for a long period of time, and in such case, life testing is a relatively lengthy procedure. Lengthy tests tend to be expensive and the results become available too late to be of much use. To reduce the experimental cost significantly and provide an efficient tool to assess the life distribution for highly reliable product, a step-stress accelerated test (SSAT) was developed. An example of a rear suspension aft lateral link is used to validate the SSAT method.

The goal of an OEM electrical/electronics (E/E) platform organization is to release reliable E/E systems that achieve high levels of customer satisfaction with minimum investment and system cost. Achieving this goal is made more challenging by rapid advances in E/E technology and features which impact the vehicle development business environment. This paper discusses the evolution of an OEM platform organization striving to achieve E/E system integrity in an ever-changing world and eventually achieved the world class electrical quality as measured by J. D. Power. The organizational evolution progresses through a series of philosophies and methodologies, adapting new initiatives and enablers seeking continuous improvement. The result is an OEM organization with: knowledge based on lessons learned, an understanding of E/E system architecture, and enabled by models and tools to provide high levels of customer satisfaction.