Metro traffic optimisation accounting for the disbenefit of halting between stations

Abstract

Computerised regulation for disturbed traffic in metro-type railways is proposed. Previous work has used optimisation techniques to minimise disbenefits to passengers, such as waiting time and journey time, in the objective function. The particular disbenefit of trains being halted between stations is introduced in this thesis, in combination with those already mentioned. An effective method in real operations for preventing trains being halted between stations is to hold trains already at stations and to allow running trains to reach the next station when a particular train departure is delayed. The proposed algorithm uses this ‘stop-all-trains-at-once’ philosophy combined with optimisation ideas, in a sequentially structured approach. A further consideration from real operations is the fact that it is not possible to predict precisely when the delayed train will re-start. Estimates of the re-starting time will improve as the delay increases, and the proposed scheme takes this into account. Numerous simulations were undertaken to investigate the performance of the regulation algorithm. It is shown that the proposed regulation algorithm is effective in reducing the disbenefit to passengers from disturbed traffic for various characteristic metros with different passenger flows