AoI-Based Communication Traffic Reduction for Networked Railway Vehicle Control

Networked railway vehicle control systems, such as communication-based train control (CBTC) systems, have been installed in recent years. CBTC and many other networked control system applications increase communication traffic and exhaust bandwidth-guaranteed communication resources. Our previous study proposed event-triggered control using the age-of-information (AoI) concept to reduce communication traffic. However, the introduction of the AoI-based event trigger is limited to forward communication from the controller to the vehicle. This study proposes the introduction of an AoI-based event trigger into feedback communication from the vehicle to the controller, in addition to forward communication. A modified communication disturbance observer (MCDOB) is implemented to compensate for time delays and data losses caused by the feedback event trigger. Simulations confirm that the proposed AoI-based method with MCDOB reduces communication traffic by up to 15.6% when the sleep period and position threshold varies, and up to 19.2% when the communication delay varies while maintaining control performance, compared to the conventional AoI-based method without MCDOB.