Visual counterexample explanation for model checking with Oeritte

Despite being one of the most reliable approaches for ensuring system correctness, model checking requires auxiliary tools to fully avail. In this work, we tackle the issue of its results being hard to interpret and present Oeritte, a tool for automatic visual counterexample explanation for function block diagrams. To learn what went wrong, the user can inspect a parse tree of the violated LTL formula and a table view of a counterexample, where important variables are highlighted. Then, on the function block diagram of the system under verification, they can receive a visualization of causality relationships between the calculated values of interest and intermediate results or inputs of the function block diagram. Thus, Oeritte serves to decrease formal model and specification debugging efforts along with making model checking more utilizable for complex industrial systems.Comment: The 25th International Conference on Engineering of Complex Computer Systems (ICECCS 2020

Formal Modeling of Testing Software for Cyber-Physical Automation Systems

Abstract-The paper presents a framework which uses formal models for testing control software for industrial automation systems. The formalism called Net Condition/Event Systems (NCES) is applied to model the program under test, along with the system under control (plant) and the testing environment. The benefits of using the framework include the opportunities to test systems with time delays without the need to wait, to test parameterized sets of systems with a single execution of a test suite, and to check test suites for correctness. The use of the framework is illustrated on a simple system consisting of a lab-scale plant and a control application for it