SAT-based Abstraction Refinement for Real-time Systems

In this paper, we present an abstraction refinement approach for model checking safety properties of realtime systems using SAT solving. With a faithful embedding of bounded model checking for systems of timed automata into propositional logic and linear arithmetic, we achieve both, quick abstraction techniques and a linear-size representation of parallel composition. In this logical setting, we introduce an abstraction that works uniformly for clocks, events, and states. When necessary, abstractions are refined by analysing spurious counterexamples using a promising extension of counterexample-guided abstraction refinement with syntactic information about Craig interpolants. To support generalisations, our overall approach identifies the algebraic and logical principles required for logic-based abstraction refinement