Guided search for hybrid systems based on coarse-grained space abstractions

Abstract

Hybrid systems represent an important and powerful formalism for modeling real-world applications such as embedded systems. A verification tool like SpaceEx is based on the exploration of a symbolic search space (the region space). As a verification tool, it is typically optimized towards proving the absence of errors. In some settings, e.g., when the verification tool is employed in a feedback-directed design cycle, one would like to have the option to call a version that is optimized towards finding an error trajectory in the region space. A recent approach in this direction is based on guided search. Guided search relies on a cost function that indicates which states are promising to be explored, and preferably explores more promising states first. In this paper, we propose an abstraction-based cost function based on coarse-grained space abstractions for guiding the reachability analysis. For this purpose, a suitable abstraction technique that exploits the flexible granularity of modern reachability analysis algorithms is introduced. The new cost function is an effective extension of pattern database approaches that have been successfully applied in other areas. The approach has been implemented in the SpaceEx model checker. The evaluation shows its practical potential.

Preface of the special issue on Model Checking of Software

“…In the sixth contribution, Bogomolov et al [3] introduce a guided search technique to detect error paths over the dynamic behavior of hybrid systems. This formalism, combining continuous and discrete dynamics, is very useful for the modeling and analysis of cyber-physical [11,15] and biological systems [2,6].…”

“…Analysis of systems with timing and other resource constraints is addressed by Jensen et al [7], where a technique for model checking weighted Kripke structures is presented. Finally, the verification of control software in cyber-physical systems is addressed by Bogomolov et al [3], who present a technique for guided search to detect error paths in hybrid systems.…”

Discrete Abstraction of Multiaffine Systems

“…The analysis of complex biological systems can signicantly benet from the theory and techniques developed in the area of hybrid systems [15,5,4,7,6,16,12,11,22,21]. The class of multiane hybrid systems [17,9] is particularly suited to model and analyze a broad range of biological systems.…”

Verification of Fault-Tolerant Clock Synchronization Algorithms

“…In this table, we compare the analysis runtime needed by the model checker SpaceEx [13,14,15] for the original and the transformed networks (the latter denoted in the table by the suffix K). Note that transformed models use only one clock for the CMs and one clock for the SMs.…”