Track Geometry

With respect to track geometry parameters, the requirements are defined in the European Standard EN13848. However due to national specifics and for historic reasons every client has different needs regarding additional parameters and their definition.
For track geometry recording EURAILSCOUT combines a non contact laser based optical gauge and an inertial measurement system. The location information is gathered by a distance measurement calculation based on the same inertial system together with odometers and satellite based D-GPS data.

Standard geometry parameters recorded are:

  • Track gauge
  • Vertical profiles (top)
  • Horizontal profiles (alignment)
  • Superelevation (cant)
  • Twist with different base lengths (calculated from the cant signal)
  • Inclination
  • Equivalent conicity
  • Cross section profile

More particular parameters such as cyclic top, cant deficiency (depending on speed) and dip angle can be part of the product as well. In fact any parameter based on the principal signals can be created.
Both inertial and chord parameters can be provided by the system. It is therefore possible to measure all track geometry parameters according to a national or customer specified standard and according to the new European standard EN 13848 on one single run.

Wave length bandwidths and threshold levels can be configured independently or according to specified standards. The system is very flexible and can meet any customer or country specific requirements.
In the diagram below is an example of the repeat precision of the track geometry system:

UFM160 GraphicTwelve measurement runs - one result: representation of the repeat precision from Left Top 3-35 m

 

In this diagram, twelve runs at different speeds, six in forward and six in reverse vehicle orientation are overlaid. The twelve individual graphs can hardly be distinguished due to the system repeatability being so tight.

The statistical analysis in the table below the graph underlines the accuracy: In average every run does not deviate more than 0.11mm from the mean of all runs. 95% of all measurement values in this section of 250 yards (220 m) deviate less than 0.27mm from the mean. At running speeds from 20 up to 80mph (35 - 120kph) this is exceptional performance.

Track graphicScreenshot of E-Capture - Fault Reporting Tool

 

For certain safety critical parameters customers define the lead time for fault reporting to be instantaneous.
Since the data is gathered and controlled in real-time additional software can run simultaneously to capture all values which exceed defined threshold levels (see screenshot above).
These faults are given a unique code and a report can be handed out at the end of the run or sent by email.