A Systematic Literature Review of the Characteristics of Automation Systems That Impact Debugging of PLC Software

The debugging capabilities of software development tools in the automation domain lag behind other domains. Basic capabilities from <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">regular</i> debuggers, such as breakpoints and step-by-step execution, are hard to find or do not support all requirements imposed by the domain. This work presents the results of a Systematic Literature Review carried out to understand the characteristics of the automation domain that influence the debugging capabilities of Programmable Logic Controller (PLC) software and to find the current state and future directions of debugging tools. The process of the review was prepared and reviewed before its execution to avoid any type of bias. The review successfully finds the major characteristics affecting the debugging of PLC software which include the presence of interconnected components and heavy machinery from different domains, the participation of different stakeholders at different phases of the development of the automation systems, and the restricted software capabilities specific to the domain. The existing debugging capabilities are mainly limited to monitoring and forcing the current state of the PLC software. However, research is being done in different areas that help debug PLC software, such as testing and simulation, and static and dynamic code analysis. The latter helps develop more powerful debugging capabilities such as the reproduction of real-time scenarios and replay debugging. The usability of debugging tools is also a subject of study in the automation domain. The work ends with an overview of future research directions to close the gap to other domains.