Complementary usage of real and virtual manufacturing systems for safe PLC training

Physical models mimicking industrial plants and relevant control issues are usually considered the most interesting targets for effective PLC (Programmable Logic Controller) training. However, they introduce safety problems. Filtering bad commands from the PLC is double interesting in this scenario: it guarantees safety and guides trainees by supplying explanations when a command is filtered. However, devising the appropriate filters can be hard for complex systems. Simulation is the single safe solution in advanced PLC training. While synthetic systems are traditionally viewed as a second-class solution in PLC training, modern computer game technologies are enabling realistic and interactive virtual environments, from where a “de facto” effective and exciting training environment comes very naturally. And filters can be relaxed in virtual environments as they only intend to help trainees in finding out their mistakes whenever a (virtual) accident happens. The paper details the design and usage of filters in PLC training. The aim is to demonstrate the benefits of the complementary usage of real and virtual target systems in PLC training, which were assessed and validated with different skilled students.