Formal model of IEC61499 syntax and its unambiguous execution semantics are important for adoption of this international standard in industry. This paper proposes some elements of such a model. Elements of IEC61499 architecture are defined in a formal way following set theory notation. Based on this description formal semantics of IEC 61499 can be defined.… (More)
In the human thalamic ventralis lateralis nucleus the spontaneous activity of 235 single units during 38 stereotactic operations in locally anaesthetized parkinsonian patients was analysed. Two basic cell types (A and B) were shown to exist in this nucleus: (i) with unitary irregular (2-40/s) discharges characterized by a tendency to spike grouping in the… (More)
– This paper proposes a formal model of IEC 61499 function blocks and systems. The model is intended to be used in description of formal semantic model of function blocks' execution. The paper outlines a number of challenges for function blocks that are supposed to be answered by the proposed model.
—The international standard IEC 61499 for the design of distributed industrial control systems defines an abstract model of function blocks (FB) which allows many different semantic interpretations. As a consequence, in addition, so-called execution models were proposed to specify the execution order of FBs. The variety of models leads to the… (More)
This paper presents a new approach to modelling and verification of function block applications of the IEC 61499 standard. The approach uses the language of logic programming Prolog to represent a model of function block network and to verify its properties. The class of properties that can be checked is extended to more substantial queries providing in… (More)
– This paper proposes a new methodology of migration from IEC 61131-3 PLCs to IEC 61499 function blocks. The aim of this migration process is to recreate IEC 61131-3 applications in IEC 61499 implementations with equivalent execution behavior. The formal model of the IEC 61131-3 standard for migration and cyclical execution model is defined. This method… (More)
—The IEC 61499 standard is designed for distributed control and proposes new visual form of programming using block diagrams with embedded state machines and unlimited hierarchical nesting and distribution across networking devices. Such visual programs require new methods of automatic syntactic and semantic analysis. This paper proposes a new approach to… (More)