The PLC UML State-chart design pattern

Abstract

We developed an UML-State-charts Object Oriented Design Pattern for PLCs IEC61131-3. This PLC UML-State-chart Design Pattern aims to explore the advantage of Object Oriented Programming by IEC61131-3 in PLCs, and to provide a direct map of UML State-chart to PLC code. We illustrates the design pattern and its use through UML Class diagrams and an application example. This Design Pattern can be used to reduce the development time of State-charts in automation software. It can also lead towards further investigations in PLC Design Patterns that may improve the whole development of automation software.