ESS Collaborative Research: A Methodology for Real-Time Train Dispatching in High Density Networks

University Of Southern California, Los Angeles CA

Investigators

Abstract

This research addresses real-time dispatching of heavy-haul trains in a high-density complex railway network with multiple-track configurations, multiple priorities and multiple speed limits. The research will provide the theory and dynamic control algorithms for deadlock-free dispatching with minimal total train delay in complex heavy-haul rail networks that are increasingly common in urban areas. Determining the optimal dispatch policies that minimizes train delays and ensures deadlock-free operations is NP-hard. Therefore, most of the research efforts in this direction have focused on developing heuristics as well as detailed simulations to plan dispatching policies. Theoretical efforts thus far have only addressed trackage configurations like single, double, and partially double rail lines. However complicating entities in a rail system like junctions, crossovers, sidings, speed limits and goods priorities need to be considered in order to extend the current theory to large-scale urban rail networks. To address this need, our research will consist of the following tasks: (1) theoretical studies focusing on developing a network representation of this complicated physical system, and characterization of the nonlinear and stochastic dynamics underlying the operations for laying the foundations of developing effective dispatching algorithms, (2) development of deadlock-free and near-optimal algorithms for the real-time dispatching of trains operating in complex general rail networks, and (3) development of a simulation methodology to model complicated rail networks akin to Southern California rail networks, and validate the performance of algorithms and theory using this simulation model. As global trade continues to increase, cargo traffic at the nation's ports continues to increase at dramatic levels. For example, the Ports of Los Angeles and Long Beach are among the busiest ports in America. Booming trade with Pacific Rim nations has seen the annual trade in the two ports exceed 100 million tons. The total volume that these ports handle is evenly divided between transcontinental and local shipments. Furthermore, a large portion of the local shipments are packaged and sorted at local facilities for shipment across the continent. Railways form the major means to transcontinentally move these goods. Forecasts show that volume growth of high-value containerized freight is set to triple in the next 25 years. The main impact of the proposed research will have a significant bearing on real-world urban rail operations, many of whose pertinent complexities have been ignored in theoretical studies thus far.