Automated Adhesion Management System (AMS) for efficient speed control and traffic management of metro trains

Abstract

EPS a OsloMet. Projecte en col·laboració amb l'empresa Sporveien AS, operadora dels serveis de transport públic a Oslo.

Currently, in Oslo there is the same number of metros running everyday regardless of the season. However, most of the lines are located outdoors and therefore exposed to climate conditions such as rain, snow and low temperatures. In order to avoid any accidents, there is a safe braking distance between metros to allow them to stop regardless of weather. Therefore, traffic on each line is not optimized because the required braking distance varies with a change in the coefficient of friction. There is a grey area on the parameters influencing adhesion and on how to predict low adhesion due to the climatic conditions. The company Sporveien AS, which takes care of the metro’s management, wants to develop an automated Adhesion Management System to calculate the safe braking distance depending on the weather. The aim of this study is to determine a methodology and design a prototype for measuring the coefficient of friction between rails and trains’ wheels. This work also includes a reflection on the way to implement this system in the railway interface. To achieve this goal and propose a solution to the adhesion problem, this report presents research to determine the parameters influencing adhesion as well as the principles to measure them. A final module is proposed with a selection of sensors to install next to the track. The working environment of this solution is also studied to describe the different interactions between it and the other entities. A sequence diagram presents the operational scenario of the global system in case of low adhesion. Finally, an estimation of braking distance is performed to understand the impact of a very low coefficient of friction depending of the speed and the slope.