Measurement of Vehicle Ground Speed with Inertia Sensors – Computation Issues

This paper proposes a new method for the measurement of train speed using bogie mounted inertial sensors, which may achieve measurement accuracy better than what is specified in UIC-5014-05 for wheel slide control. The proposed method measures the speed from a time shift between the dynamic motions of two wheelsets which are derived from the responses of a railway bogie to track excitations, in particular track irregularities that always exist in rail tracks. Two inertial sensors will be required and mounted onto a bogie frame to measure the bounce and pitch accelerations (or lateral and yaw accelerations). The measured signals will be processed via dedicated filters to produce estimated wheelset movements (i.e. the track irregularities). The principle of the proposed method will be presented, but the paper will be mainly focused on the assessment of computational demand and impact on measurement performance.