A qualitative study of variability management of control software for industrial automation systems

Software product line engineering (SPLE) provides a systematic approach to manage variants and versions arising throughout the development of software systems. While SPLE is successfully applied for variant management in the domain of software engineering, the approach is still not widely spread in industrial automated production systems (aPS). Previous studies highlight the interdisciplinary nature of aPS as a reason for not applying SPLE, since control software variants and versions also result from changes in other disciplines such as the mechanical engineering department (i.e. exchange of a sensor). Additionally, the software may evolve over decades at the customer site. In order to gain a better understanding of the challenges in the development of aPS and the constraints hindering the use of SPLE, we conducted several interviews with software development engineers from the domain of aPS. The interviews main aim was to get an overview of the current state of variability management and applied planned and unplanned software reuse strategies. Based on these insights, we summarize the main results useable for a transition from currently deployed variability management concepts in aPS to the SPLE approach.