Concept for Reproducible Braking Distance

Abstract

The constant urbanization requires the increase of transport capacities. At the same time, however, the expansion of the rail infrastructure is often only possible with great difficulty, if at all, in densely populated areas. Therefore, a central goal is to increase the utilization of the existing infrastructure. One way to achieve this is to shorten the train headways and thus to be able to run more trains per time on a line. Among other control variables, the variation of braking distances is one reason for possible margins in the system. Knorr Bremse is working on minimizing this variation with the aid of intelligent functions and control algorithms. The functions are compensating the tolerances within the technical system on the train as well as the different environmental conditions on the track. The Reproducible Braking Distance concept by Knorr Bremse is formed firstly by a deceleration control algorithm that will be in the end applied in emergency brake application. Secondly an adaptive Wheel Slide Protection System selects the best control strategy under given track conditions and is optimizing the worst cases of adhesion conditions on railways. A third pillar is the adhesion management which aims to improve adhesion in the wheel/track contact point by means of intelligent use of sanding systems in a first step. The benefits of such a concept are interesting for train operators as trains will have a more predictable braking behavior which serves the train driver. In an Automated Train Operation System the margins for brake distance variations can be reduced. A Joint research project with IFB Institut für Bahntechnik GmbH investigated the potential effect on infrastructure utilization. Depending on train type, signaling, and distance between stops, calculations showed a reduction in headways of between five and 20 percent. These functions are tested on Knorr Bremse ATLAS (Advanced Test Laboratory for Adhesion based Systems) test rig and will be used for the first time in the new product generations.