Conversion of LSAT behavioral specifications to automata

The Logistics Specification and Analysis Tool (LSAT) is a model-based engineering tool used for manufacturing system design and analysis. Using a domain specific language, a system can be specified in LSAT. In this paper, a conversion method is presented to obtain the system behavior of an LSAT specification in automata structure.Comment: 10 pages, 6 figure

Efficiently enforcing mutual state exclusion requirements in symbolic supervisor synthesis

Given a model of an uncontrolled system and a requirement specification, a supervisory controller can be synthesized so that the system under control adheres to the requirements. There are several ways in which informal behavioral safety requirements can be formalized, one of which is using mutual state exclusion requirements. In current implementations of the supervisor synthesis algorithm, synthesis may be inefficient when mutual state exclusion requirements are used. We propose a method to efficiently enforce these requirements in supervisor synthesis. We consider symbolic supervisor synthesis, where Binary Decision Diagrams are used to represent the system. The efficiency of the proposed method is evaluated by means of an industrial and academic case study

Transformational supervisor synthesis for evolving systems

Supervisory controller synthesis is a means to compute correct-by-construction controllers for discrete event systems. As these systems and their requirements evolve over time, an updated supervisor needs to be computed each time an adaptation takes place. We consider the case that a supervisor has been synthesized for a given model, after which this model is (slightly) adapted. We investigate how we can make use of the previous synthesis result, in order to more efficiently compute the supervisor for the adapted model. We introduce model deltas as a means to describe the difference between pairs of models. Using the model deltas, a notion of atomic adaptations is introduced. For these atomic adaptations, algorithms are provided to compute the supervisor for the adapted model in a transformational manner from the previous synthesis result, rather than performing a completely new synthesis. These atomic adaptations can be iterated over, to transformationally compute a supervisor for model deltas that contain a number of atomic adaptations. To improve efficiency, it is shown how atomic adaptations can be grouped together based on their required computations and be processed at the same time. A running example is used to support the explanations on the functioning of the algorithms. The efficiency of the method is evaluated by means of both an academic and an industrial use case

Correction to:Transformational supervisor synthesis for evolving systems

The paper mentioned in the title used an incorrect implementation of the algorithms to produce the experimental results. The mistake significantly impacts the computational efficiency of the algorithms, on which they are evaluated. In this correction we explain the mistake, present the new results, and update our conclusions based on the new results.</p

Transformational Supervisor Localization

Supervisor localization can be applied to distribute a monolithic supervisor into local supervisors. Performing supervisor localization can be computationally costly. In this work, we consider systems that evolve over time. We study how to reuse the results from a previous supervisor localization, to more efficiently compute local supervisors when the system is adapted. We call this approach transformational supervisor localization, and present algorithms for the procedure. The efficiency of the procedure is experimentally evaluated.Comment: Accepted for IEEE Control Systems Letters (L-CSS) (2023

Transformational Nonblocking Verification

Nonblocking verification can be applied to evaluate the behavior of discrete event systems. Performing nonblocking verification can be computationally costly. In this work, we consider discrete event systems that evolve over time. We study how to reuse results from a previous nonblocking verification, to more efficiently perform nonblocking verification when the system is adapted. We call this approach transformational nonblocking verification, and present an algorithm for the method. The efficiency of the method is evaluated by applying an academic and an industrial use case