Offline Reproduction of Function Block Networks in IEC 61499 Resources

The debugging capabilities in the automation domain lag behind those in other domains. One obstacle to debugging systems in the automation domain is the presence of heavy and costly machinery connected to the Programmable Logic Controllers (PLCs). Replay debugging presents an opportunity to overcome this issue by allowing the user to debug a system with full control and observability, without the real system being connected. During the first stage of replay debugging, information is captured while the system is running. This is then used during the second stage to reproduce the system in a safe environment.This work focuses on a viability analysis of replay debugging for Function Block networks within resources modelled according to the IEC 61499 standard. In order to reduce the execution impact of information capture, the work presents an approach where only a small subset of the run-time information is captured and can be used in an offline stage to generate the full execution behaviour of an IEC 61499 resource. Thorough tests and experiments show that the reproduction of the original states is possible.