Suppose we are given a schedule of train movements over a rail network into which a new train is to be included. The origin and the destination are specified for the new train; it is required that a schedule (including the path) be determined for it so as to minimize the time taken without affecting the schedules for the old trains. In the standard formulations of this single train pathing problem, the time taken by the train to traverse any block (track segment guarded by a signal) in the network is deemed to be a fixed number independent of how the train arrived onto that block. In other words, the standard formulations of train pathing do not accurately model the acceleration/deceleration restrictions on trains. In this paper we give an algorithm to solve the single train pathing problem while taking into account the maximum allowed acceleration and deceleration as well as explicitly modeling signals. For trains having `large' maximum acceleration and deceleration, our algorit...
Viswanath Nagarajan, Abhiram G. Ranade