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In recent automotive systems, more and more applications are classified as safety related and hence are assigned an automotive safety integrity level (ASIL) according to ISO26262. Especially in the context of advanced driver assistance systems (ADAS) and automated driving, safety, reliability and availability requirements are ever increasing. In upcoming systems, a classical fail-safe design will not be sufficient in order to fulfill these requirements, and hence fail-operational systems will be essential. This holds especially true when it comes to automated driving levels 4 and 5. On the other hand, well-known approaches from the avionics industry are ill-suited for the use in automotive systems due to space, weight and power (SWAP) restrictions. This motivates the research on new, lightweight approaches for embedded fail-operational systems.

Various algorithms such as emergency brake or crash warning using V2X communication have been published recently. For such systems hard real-time constraints have to be satisfied. Therefore latency needs to be minimized to keep the message processing delay below a certain threshold. Existing V2X systems based on the IEEE 1609 and SAE J2735 standards implement most message processing in software. This means the latency of these systems strongly depends on the CPU load as well as the number of incoming messages per time. According to safety constraints all messages of nearby vehicles have to be processed, whereby no prediction of the message importance can be given without analyzing the message content. Regarding the aforementioned requirements we propose a novel architecture that optimizes latency to satisfy the hard real-time constraints for V2X messages.

Service-oriented architectures (SOAs) are well-established solutions in the IT industry. Their use in the automotive domain is still on the way. Up to now, the automotive domain has taken advantage of service-oriented architectures only in the area of infotainment and not for systems with hard real-time requirements. However, applying SOA to such systems has just started but is missing suitable design and verification methodologies. In this context, we target to include the notion of model-based design to address fail-operational systems. As a result, a model-based approach for the development of fail-operational systems based on dynamic reconfiguration using a service-oriented architecture is illustrated. For the evaluation, we consider an example function of an automatically controlled braking system and analyze the reconfiguration time when the function fails.