RAMS is Not Enough! The Design of a Software Integration Risk Analysis Matrix (SIRAM) for Assessing the Impact of Software Integration on Physical System Performance

Physical assets are increasingly digitally enhanced using software and associated information technologies. These added functionalities make them more complex to engineer and maintain as they depend on additional software and information technology components. However, the available RAMS analysis methodologies do not explicitly include software application and integration. We propose a software integration risk matrix (SIRAM) as an extension of the current RAMS methodology, to assess the effect of software on overall system performance. This extension can aid decision-making by indicating the expected software's integration impact on system performance and maintenance needs and is developed using design science research methodology (DSRM). A case study within the Dutch railways served as the basis for the design and testing of the proposed matrix. The testing shows that the proposed software integration risk matrix can add value by managing that critical software impacts will be part of the system integration process.

Keywords: RAMS, Software, Information technology, System integration, IT/OT convergence, Railways.