抄録
This paper provides a comprehensive examination of a new measurement technique for detecting absolute train speed using two bogie inertial sensors which may be used to replace or supplement the conventional methods of deriving vehicle travelling speed from wheel/axle rotation as commonly seen in railway (as well as automotive) applications. The new method measures the speed from a time delay between the bounce 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. The measured signals will be processed to produce estimated wheelset movements (i.e. the track irregularities) and the time shift between the two is then detected using cross correlation calculations which is directly related to the vehicle speed. Because the new technique is independent of the wheel/axle rotations, the measurement will not be affected by any wheel slip/side which often occurs in traction and braking, especially in poor adhesion conditions.
