Railway track position measuring system using laser beam

摘要

The positioning apparatus for a railway track (A) with respect to a reference rail (B) comprises a vehicle which runs on the railway track to be measured. The vehicle includes a position measuring device mounted on board. This includes a laser transmitter and a camera for forming an image of that part of the reference rail struck by the laser beam. The axis of the laser beam may be adjusted in a vertical plane and the image produced by the camera may be compared with a reference. The position of the camera and the adjusted position of the laser beam are used to deduce the position of the railway track with respect to the reference rail.