Digital twins: An analysis framework and open issues

The concept of twinning an operational physical system with a functional replica is not new, having been practiced in the space sector for over 50 years. Advances in digitalisation have created opportunities to extract data, obtain insights and achieve greater situational awareness of a physical system's performance. Increasing interest in the concept has led to a proliferation of digital twin definitions, which are used to frame discussions about specific digital twins. Consequentially comparison of the capabilities of specific digital twins is difficult as they are analysed using different definitions. This paper proposes an analysis framework that enables the characteristics of all digital twins to be matched to this framework. Using this framework, a digital twin may be characterised, or two or more digital twins may be compared. By establishing a framework that contains common functional characteristics, we aim to reduce the confusion caused by the plethora of digital twin definitions and their interpretation by suppliers. By focusing only on functionality and not addressing non-functional re-quirements the analysis allows comparison of different physical and logical instantiations of digital twins.