Abstract: Quadruped robots which have flexibility and load-bearing capacity, are regarded as the best mobile platform for remote operation in unstructured and restricted environments. In the process of remote operation of quadruped robots, their status is inevitably influenced by complex environments. To monitor the robot's real-time operation status and make necessary adjustments, this paper focuses on the single-leg of a quadruped robot, proposes a single-leg virtual–real interaction system based on Digital Twin, and studies its virtual–real interaction characteristics. The virtual–reality interaction system contains single-leg physical entity, single-leg virtual model, control system, data service system and communication system, enabling interactive applications for single-leg visual state monitoring and real-time control optimization. This paper creates a high-fidelity model based on the physical entity; provides a system performance analysis method based on the system framework; analyzes virtual–real interaction delay based on communication scheme; conducts stand and jump test based on the single-leg mathematical model and analyzes the interaction characteristics under position/force control. This system provides new insights for real-time monitoring and control optimization of quadruped robots.

Key words: Quadruped robot , · Digital twin , · Virtual–real interaction , · Performance analysis , · High-fidelity model