Abstract:

PLC, Programmable Logic Controller (PLC), is the most common control device for automation systems. PLC programming know-how is a vital part of core competencies of automation engineers. Usually curriculums of automation engineering education includes one or two courses of PLC technology and PLC programming, but often PLC know-how is also needed in several other courses. The development of the PLC, especially during the last few decades, emphasizes the meaning of PLC programming. Very often, the PLC is a part of information management of the whole factory and is integrated in to several other information systems. This is also possible and modern PLC offers features for this.

The basics of PLC programming have usually been taught and studied in class with scale-models of automated machines and devices, which have been connected to PLC. These kinds of laboratory devices are rather expensive and laboratory premises are often limited, so other options to conduct teaching should also be considered. Remotely controlled laboratory devices and systems offer the opportunity to use common laboratory devices remotely, independent of time and place. However, these kinds of solutions still need some monitoring and service. This solution can improve learning environments usability and students can use devices even from home. Another way to replace traditional laboratory devices is to use virtual devices. Typical virtual devices are interactive animations, which can be used for studying certain parts of programming. The development of web technology and the PLC have made it possible to build more illustrative and authentic virtual devices so that PLC-programming can be done by using normal the PLC-programming environment.

In this study, we have designed and built a virtual environment for studying PLC-programming. This virtual learning environment includes several virtual devices and systems. Virtual devices are integrated with TwinCat, SoftPLC and its programming environment. Basics of PLC-programming can be studied by using a 3D-environment made by a game engine and integrated in PLC programming application. In this case, a student can download both applications, programming application and virtual model, on his computer and complete independently given exercises.

In order to use this environment, we conducted a Basics of PLC-programming course for two student groups in the summers 2010 and 2011. Learning environments suitability for studying PLC-programming was evaluated by survey research targeted to students. In addition, some students and teachers, who used the environment, have been interviewed more precisely. The aim of this study was to make clear that while using the virtual environment, the students experience it as an efficient method for learning PLC programming and if feel that they have learned PLC programming well by using the environment. Both, survey results and interviews of the students and teachers prove that a developed virtual learning environment is especially suitable for studying PLC-programming and students want the use, and development of the environment could be extended and expanded. Students also felt that use of the environment was very easy and built virtual models were very illustrative.

Keywords:

Virtual environments, simulation, automation engineering.