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RAMS analysis of GNSS based localisation system for the train control application

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Global Navigation Satellite Systems (GNSS) is usually used in non-safety-related applications for various transportation modes. In order to employ GNSS (Global Navigation Satellite Systems) for train control application, numerous projects study if performance of GNSS can satisfy the railway safety requirements. In the railway context, multiple obstacles in local environments can cause different signal perturbations that lead to negative consequences on the position accuracy. Reinforcing the position quality for safety-related applications is necessary. In this context, the European Project - GaloROI is on going. Its working principle is based on the combination of data from GNSS receiver and an Eddy Current Sensor (ECS). According to the development process of GaLoROI system, the dependability and safety analysis is an essential mission in order to prove if it satisfy the safety railway standards. In this paper, we present a procedure for predictive RAMS analysis of a localisation unit based on the combination of GNSS & ECS for the application ”control the braking loop”. Besides capturing multiple local impacts on satellite signal quality, this approach allows us to analyse complex behaviours of the sensor fusion component and also to take into account the reliability parameters of hardware components.
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GPS/GNSS based train position locator for railway signalling
  • A Filip
  • L Bazant
  • H Mocek
  • J Cach
A. Filip, L. Bazant, H. Mocek & J. Cach, GPS/GNSS based train position locator for railway signalling, Computers in Railways VII, 2000, ISBN 1-85312-826-0
Railway applications specification and demonstration of reliability, availability, maintainability and safety (RAMS) Part 2: Guide to the application of EN50126-1
EN 50126-2, 2007. Railway applications specification and demonstration of reliability, availability, maintainability and safety (RAMS) Part 2: Guide to the application of EN50126-1. CENELEC European technical report (European Committee for Electrotechnical Standardization).
Railway applications communication, signalling and processing systems safety related electronic systems for signalling
EN 50129, 2003. Railway applications communication, signalling and processing systems safety related electronic systems for signalling. CENELEC European standard (European Committee for Electrotechnical Standardization).