GNSS for Enhanced Odometry: The GRAIL-2 results

GRAIL-2 is the evolution of the GRAIL project (GNSS introduction in the RAIL Sector), a project funded by the GSA (GNSS Supervisor Authority) with the aim of facilitating the introduction of GNSS (Galileo and EGNOS) in the Rail sector. GRAIL-2 takes over it predecessor focusing on the development of a GNSS based Enhanced Odometer with high integrity and safety level in a context of High Speed Lines (HSL). The purpose of a GNSS based odometer is to integrate and/or replace the traditional odometric systems currently used in the ETCS environment (tachometers, INS, Doppler radar etc.). GRAIL-2 inherits the know-how acquired by GRAIL improving the accuracy of the computed Position-Velocity-Acceleration solution by means of an advanced data fusion algorithm. The safety level is guaranteed introducing RAIM and Protection Level computation algorithms. The purpose of this paper is to describe the results obtained analyzing the preliminary data captured on the train.