A Comprehensive Review of Virtually Coupled Train Systems

Virtual coupling (VC) has attracted increasing research attention as a train control concept for rail systems, enabling trains to operate at very short separations using cooperative, relative distance-based control. This paper reviews how VC affects railway operations across three interconnected layers: operation control, transport organi- zation and system-level performance evaluation. At the control layer, we synthesize research on separation and col- lision avoidance models, trajectory planning, formation and cooperative control, and uncertainty-aware control