Formal Properties of the Digital Twin – Implications for Learning, optimization, and Control

Digital twins are regarded as enablers of smart and autonomous manufacturing systems. The digital twin concept essentially refers to a ultra-realistic digital model of a products or system, coupled by a bidirectional automated data exchange, used for simulation, optimization, and control. Although the concept has gained significant attention, its conceptual basis is still weak. We review common definitions and descriptions of digital twins and refine the concept in system theoretic terms. With this sharpened perspective on digital twins, we sketch out three basic problems that need to be solved to turn a digital model into a digital twin. To that end, we call attention to challenges that need to be researched into.