Symmetry-Based Decoupled Extended Reality and Digital Twin Framework for Robotic Manipulators

This paper presents a decoupled Extended Reality (XR) and Digital Twin (DT) framework for robotic manipulators, leveraging mathematical, physical, and topological symmetries to achieve stable cyber–physical synchronization. Traditional robotic teleoperation architectures suffer from tight coupling between low-level control, communication, and visualization interfaces, making them vulnerable to network latency and platform dependencies. We propose an open, modular framework that structurally decouples physical and virtual counterparts. By establishing a system-theoretic formulation of Digital Twin symmetry, we represent the virtual robot as an isomorphic state-space mirror of the physical manipulator. Communication is mediated by an asynchronous, network topology using a lightweight Message Queuing Telemetry Transport (MQTT) broker, ensuring topic-based communication symmetry. This decoupled structure enables a highly flexible, many-to-many evaluation paradigm, allowing researchers to interchangeably pair a single physical robot with diverse user interfaces (UIs) or control multiple heterogeneous robots (physical and simulated) with a single virtual interface. Experimental validation on a 7-Degree-of-Freedom (7-DOF) Franka Emika Panda robot and a unified data collector confirms high-fidelity tracking, with a symmetric wired and wireless Round-Trip Times (RTT) averaging 47 ms. Finally, we discuss the challenges of transitioning this laboratory-scale architecture to high-concurrency industrial settings, addressing single-broker vulnerabilities, network jitter, and dynamic calibration drift.