Challenges in Constraint-Based Analysis of Hybrid Systems

Abstract

Abstract. In the analysis of hybrid discrete-continuous systems, rich arithmetic constraint formulae with complex Boolean structure arise naturally. The iSAT algorithm, a solver for such formulae, is aimed at bounded model checking of hybrid systems. In this paper, we identify challenges emerging from planned and ongoing work to enhance the iSAT algorithm: First, we propose an extension of iSAT to directly handle ordinary differential equations as constraints. Second, we outline the recently introduced generalization of the iSAT algorithm to deal with probabilistic hybrid systems and some open research issues in that context. Third, we present ideas on how to move from bounded to unbounded model checking by using the concept of interpolation. Finally, we discuss the adaption of some parallelization techniques to the iSAT case, which will hopefully lead to performance gains in the future. By presenting these open research questions, this paper aims at fostering discussions on these extensions of constraint solving.

Automated generation of hybrid automata for multi-rigid-body mechanical systems and its application to the falsification of safety properties

“…[71][72][73][74]. SMT-based BMC is becoming increasingly important in practical applications and hybrid systems, for example iSAT [75,76], MathSAT [77], Absolver [78,79], verification of networks of linear hybrid automata [80], bounded reachability analysis for linear hybrid automata [81] and the recent bounded model-checker dReach [82] that uses the SMT solver dReal [83,84]. Whilst some of these tools (iSAT, Absolver and dReach with dReal) can be mainly applied to non-linear dynamical systems and some types of hybrid systems, they cannot be directly applied to our systemsnon-linear hybrid automata, with a high number of different types of discrete locationsin their present form.…”

Efficient Solving of Large Arithmetic Constraint Systems with Complex Boolean Structure

“…See [53] for a summary of these endeavours, which are carried out at the universities of Freiburg and Oldenburg within the AVACS project. See [53] for a summary of these endeavours, which are carried out at the universities of Freiburg and Oldenburg within the AVACS project.…”