Effective Underground Facilities Management in Virtual Reality by Applying a Cybersickness Reduction Technique Based on a Four-Degree-of-Freedom Motion Simulator

Managing underground utility tunnels (UUT) poses challenges such as safety risks, limited accessibility, and high training costs. To address these, we developed an effective VR-based UUT management training simulator, integrating digital twins with a multi-degree-of-freedom (DoF) motion platform to provide an immersive, cybersickness-reducing experience. Advances in actuator and computer graphics technology have increased the research and development of virtual reality (VR)-based training simulators that use multi-DoF motion platforms. In this study, the proposed system provides precisely synchronized visual feedback through a head-mounted display and kinematic feedback via four-DoF motor-based actuators, realistically simulating UUT conditions, including momentum shifts such as falls and micro-swaying. To mitigate cybersickness, visual and kinematic acceleration control techniques are employed, ensuring users can comfortably and safely experience the UUT without stability concerns. We used a LiDAR sensor to model the actual UUT for realistic visualization in the VR environment and created various scenario-based content, such as facility installation, inspection, and device repair, based on the physical characteristics inside the UUT. This integrated approach enables users to effectively manage and operate UUT facilities in a safe, controlled virtual setting, bridging the gap between traditional training and real-world operations.