A simple in-cab schedule advisory system to save energy and improve on-time performance

Halcrow and Unipart Rail have developed and are trialling a simple in-cab system which continually advises train drivers of the train's time with respect to a pre-calculated time-distance profile. The profile is set up to save energy by making use of unused recovery time in the timetable. The recovery time is used up at the end of each inter-station journey by "coasting", i.e. reducing power to idle and allowing the train to decelerate gradually. An off-train performance calculator is used to generate the profiles for each stopping pattern, route and rolling stock type. The profile fully respects the stops and important passing points in the operating timetable. The system is very easy to use and requires only a power supply from the train. It can be quickly installed on legacy and mid-life rolling stock. It comprises an in-cab display, a processor unit and a GPS receiver. The software element of the system will also be able to be run on most train management systems and on recent rolling stock which already has on-board processing power and GPS feeds and so will need no additional hardware. The algorithm used by the system adjusts the coasting position according to whether the train is early or late to maximise the energy-saving potential whilst ensuring that no important timing point is missed through coasting. The basic driver's display consists of just two screens a train selection screen and a real time display. Once the train has been selected at the start of its run, the real time screen shows the current position against its timetable. A simple graphic display shows time ahead or behind, with a numeric indicator as well. The driver need only glance at the unit to be aware of the train's time against its timetable. When the train approaches a coasting opportunity, provided it is not so late that any coasting wo