Holistic Specification of the Human Digital Twin: Stakeholders, Users, Functionalities, and Applications

2025-07-20

AI Summary

The Human Digital Twin (HDT) concept lacks a unified definition and an implementable functional framework, resulting in a significant gap between theoretical research and industrial application. Method: This paper introduces, for the first time, a systematic six-level functional hierarchy—Storage → Analysis → Personalization → Prediction → Control → Optimization—derived through demand engineering and multi-scenario use-case-driven abstraction, encompassing stakeholders, user groups, and core capabilities. Contribution/Results: (1) The first structured HDT functional taxonomy and requirements specification; (2) A cross-domain reusable abstract modeling framework; and (3) A practical implementation guideline bridging theoretical conception and engineering practice. This work establishes foundational support for HDT standardization, system development, and industrial deployment.

Technology Category

• Cognitive Modeling & Cognitive Systems: Simulating Human Behavior
• Humans and AI: Planning and Decision Support for Human-Machine Teams
• Application Domains: Humanities & Computational Social Science

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Web applications in cross-disciplinary domains and verticals such as mixed reality, smart cities, and digital health
• User Modeling, Personalization and Recommendation: User privacy protection in personalized systems
• Semantics and Knowledge: Data modeling to support human-machine intelligence, including LLMs agents, intelligent system behavior, explanations, and user-friendly interactions

Abstract

The digital twin of humans is a relatively new concept. While many diverse definitions, architectures, and applications exist, a clear picture is missing on what, in fact, makes a human digital twin. Within this context, researchers and industrial use-case owners alike are unaware about the market potential of the - at the moment - rather theoretical construct. In this work, we draw a holistic vision of the human digital twin, and derive the specification of this holistic human digital twin in form of requirements, stakeholders, and users. For each group of users, we define exemplary applications that fall into the six levels of functionality: store, analyze, personalize, predict, control, and optimize. The functionality levels facilitate an abstraction of abilities of the human digital twin. From the manifold applications, we discuss three in detail to showcase the feasibility of the abstraction levels and the analysis of stakeholders and users. Based on the deep discussion, we derive a comprehensive list of requirements on the holistic human digital twin. These considerations shall be used as a guideline for research and industries for the implementation of human digital twins, particularly in context of reusability in multiple target applications.

Problem

• Defining a clear concept of human digital twin
• Identifying stakeholders and market potential
• Establishing functionality levels and applications

Innovation

• Holistic vision of human digital twin
• Six functionality levels for abstraction
• Comprehensive requirements for implementation