Christian Buckl

Chih-Hong Cheng, Saddek Bensalem, Yu-Fang Chen et al.

We present algorithms to synthesize component-based systems that are safe and deadlock-free using priorities, which define stateless-precedence between enabled actions. Our core method combines the concept of fault-localization (using safety-game) and fault-repair (using SAT for conflict resolution). For complex systems, we propose three complementary methods as preprocessing steps for priority synthesis, namely (a) data abstraction to reduce component complexities, (b) alphabet abstraction and #-deadlock to ignore components, and (c) automated assumption learning for compositional priority synthesis.

Klaus Becker, Bernhard Schatz, Christian Buckl et al.

In domains like automotive, safety-critical features are increasingly realized by software. Some features might even require fail-operational behavior, so that they must be provided even in the presence of random hardware failures. A new fault-tolerant SW/HW architecture for electric vehicles provides inherent safety capabilities that enable fail-operational features. In this paper we introduce a formal model of this architecture and an approach to calculate valid deployments of mixed-critical software-components to the execution nodes, while ensuring fail-operational behavior of certain components. Calculated redeployments cover the cases in which faulty execution nodes have to be isolated. This allows to formally analyze which set of features can be provided under decreasing available execution resources.