--- res: bibo_abstract: - "Hybrid automata combine finite automata and dynamical systems, and model the interaction of digital with physical systems. Formal analysis that can guarantee the safety of all behaviors or rigorously witness failures, while unsolvable in general, has been tackled algorithmically using, e.g., abstraction, bounded model-checking, assisted theorem proving.\r\nNevertheless, very few methods have addressed the time-unbounded reachability analysis of hybrid automata and, for current sound and automatic tools, scalability remains critical. We develop methods for the polyhedral abstraction of hybrid automata, which construct coarse overapproximations and tightens them incrementally, in a CEGAR fashion. We use template polyhedra, i.e., polyhedra whose facets are normal to a given set of directions.\r\nWhile, previously, directions were given by the user, we introduce (1) the first method\r\nfor computing template directions from spurious counterexamples, so as to generalize and\r\neliminate them. The method applies naturally to convex hybrid automata, i.e., hybrid\r\nautomata with (possibly non-linear) convex constraints on derivatives only, while for linear\r\nODE requires further abstraction. Specifically, we introduce (2) the conic abstractions,\r\nwhich, partitioning the state space into appropriate (possibly non-uniform) cones, divide\r\ncurvy trajectories into relatively straight sections, suitable for polyhedral abstractions.\r\nFinally, we introduce (3) space-time interpolation, which, combining interval arithmetic\r\nand template refinement, computes appropriate (possibly non-uniform) time partitioning\r\nand template directions along spurious trajectories, so as to eliminate them.\r\nWe obtain sound and automatic methods for the reachability analysis over dense\r\nand unbounded time of convex hybrid automata and hybrid automata with linear ODE.\r\nWe build prototype tools and compare—favorably—our methods against the respective\r\nstate-of-the-art tools, on several benchmarks.@eng" bibo_authorlist: - foaf_Person: foaf_givenName: Mirco foaf_name: Giacobbe, Mirco foaf_surname: Giacobbe foaf_workInfoHomepage: http://www.librecat.org/personId=3444EA5E-F248-11E8-B48F-1D18A9856A87 orcid: 0000-0001-8180-0904 bibo_doi: 10.15479/AT:ISTA:6894 dct_date: 2019^xs_gYear dct_isPartOf: - http://id.crossref.org/issn/2663-337X dct_language: eng dct_publisher: Institute of Science and Technology Austria@ dct_title: Automatic time-unbounded reachability analysis of hybrid systems@ ...