Exploring the Boundaries of Decidable Verification of Non-Terminating Golog Programs

Abstract

The action programming language GOLOG has been found useful for the control of autonomous agents such as mobile robots. In scenarios like these, tasks are often open-ended so that the respective control programs are non-terminating. Before deploying such programs on a robot, it is often desirable to verify that they meet certain requirements. For this purpose, Claßen and Lakemeyer recently introduced algorithms for the verification of temporal properties of GOLOG programs. However, given the expressiveness of GOLOG, their verification procedures are not guaranteed to terminate. In this paper, we show how decidability can be obtained by suitably restricting the underlying base logic, the effect axioms for primitive actions, and the use of actions within GOLOG programs. Moreover, we show that dropping any of these restrictions immediately leads to undecidability of the verification problem.

Verifying ConGolog Programs on Bounded Situation Calculus Theories

“…There has been significant interest in reasoning about and verifying agent programs, such as Shapiro, Lespérance, and Levesque (2002; (Claßen and Lakemeyer 2008;Claßen et al 2014;De Giacomo, Lespérance, and Pearce 2010;Sardina and De Giacomo 2009) based on ConGolog programs "characteristic graphs". 4 However, these approaches generally impose important restrictions, such as propositional agents and/or simple programs (e.g., with pick variables ranging over finite domains), or resort to verification via theorem proving and fixpoint approximation with no decidability guarantees.…”

SMT Safety Verification of Ontology-Based Processes

“…In spirit, our approach is reminiscent of previous works studying the verification of dynamic systems, like Golog programs, operating over a DL ontology, such as those by Claßen et al (2014), and Zarrieß and Claßen (2016). In fact, both in their settings and ours, the dynamic system evolves each model of the ontology, and properties are verified over all the resulting evolutions.…”

Situation calculus for controller synthesis in manufacturing systems with first-order state representation

“…With the theory and framework in place, a next step is to devise actual tools for the synthesis of manufacturing processes, that are based on a ConGolog formalization. In this respect, possible approaches to start from are, e.g., those of [56], based on predicate abstraction, or [57,58], where verification is addressed by resorting to First-Order BDDs, and [59], where (LTL) realizability is addressed by compilation into safety and reachability games.…”