Exploring Human-in-the-Loop Integration in the Operation of Digital Twin Applications

Human-in-the-loop integration in the operation of Digital Twins has emerged as a critical research direction to advance their fidelity in representing real-world entities. Although a wide range of frameworks, interaction models and architectures exist for integrating humans into information systems, the systematic involvement of humans in the operation of Digital Twins remains limited. In this paper, we present a structured literature survey focusing on the current state of human-in-the-loop integration within Digital Twin implementations. We systematically analyze peer-reviewed studies that incorporate human-in-the-loop approaches into real implementations and prototypes of Digital Twins, and identify the types and characteristics of these integrations. We compare human roles, interaction elements, degrees of human involvement (according to an established Digital Twin framework), and the interfaces for human interaction. As an additional outcome of the survey, we identify key challenges and open research questions that inform the development of a roadmap for future work in this evolving interdisciplinary field.