Details

Autor(en) / Beteiligte

• Moggi, Eugenio
• Farjudian, Amin
• Duracz, Adam
• Taha, Walid

Titel

Safe & robust reachability analysis of hybrid systems

Ist Teil von

• Theoretical computer science, 2018-11, Vol.747, p.75-99

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2018

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Hybrid systems—more precisely, their mathematical models—can exhibit behaviors, like Zeno behaviors, that are absent in purely discrete or purely continuous systems. First, we observe that, in this context, the usual definition of reachability—namely, the reflexive and transitive closure of a transition relation—can be unsafe, i.e., it may compute a proper subset of the set of states reachable in finite time from a set of initial states. Therefore, we propose safe reachability, which always computes a superset of the set of reachable states. Second, in safety analysis of hybrid and continuous systems, it is important to ensure that a reachability analysis is also robust w.r.t. small perturbations to the set of initial states and to the system itself, since discrepancies between a system and its mathematical models are unavoidable. We show that, under certain conditions, the best Scott continuous approximation of an analysis A is also its best robust approximation. Finally, we exemplify the gap between the set of reachable states and the supersets computed by safe reachability and its best robust approximation. •Safe reachability is a closed subset over-approximating the set of reachable states.•Safe reachability correctly handles hybrid systems with Zeno behaviors.•The definitions of safe reachability and safe evolution do not rely on trajectories.•Robustness is a property of an analysis computing closed subsets of a metric space.•We give sufficient conditions for the existence of best robust over-approximations.