Energy optimised driving style management using a satellite-based train positioning platform

European rail-based traffic is currently in a state of radical change and technical innovations are opening up more and more new opportunities for rail transport improvement. Based on the Global Positioning System (GPS), the train positioning system OPTIVIA developed by DaimlerChrysler Rail Systems (Signal) GmbH combines data from a variety of sources and provides accurate and reliable position data which can be used to optimise the transport process without a cost intensive infrastructure. The paper presents the principle and the performance of the GPS-based train positioning system. The system uses data collected from the GPS receiver, odometer and route database to achieve required positioning accuracy and availability. Although the sensors used have both strength and weaknesses, by combining the complementary strengths of the sensors, the train positioning system is able to determine accurate and reliable speed and position data. For example, odometer data can be calibrated from the available accurate GPS positioning data. Conversely the calibrated odometer data can provide reliable positioning when GPS positioning is not available during signal shadowing phases. With the integrated positioning data, the actual track related data (ramp, curve, speed limit, stopping point, tunnel, etc.) can be extracted from the route data base. As an useful application for satellite based train positioning system the energy optimised driving style manager is presented here. Depending on track condition, load situation and time table, energy can be optimised by controlling tractive force, regenerative braking and energy storage. This system is scheduled to be tested on the Adtranz ICN (Swiss intercity tilting train) in 2000.