Light-Rail Envelope Curve

Use this tool to calculate tractrices for light-rail vehicles, for subsequent visualization. Define the progression of the envelope in different ways, such as polyline, 2 rails, shunting route or barrier.

The result can be visualized in 2D or 3D with various levels of detail. The program uses the track gauge of the configured vehicle to determine and display the position of the right and left rails. These lines can also be stored in the DGN if required.

There is also an option to compare the envelope intersection points with lower points on the envelope and to move the intersection contour outwards. The "Section level only" switch must then not be activated. When analyzing platform edges, only the section level is taken into account, since the lower envelope contour points have sufficient space to the side and are therefore not relevant.


  • Create envelopes for buses and trains
  • Cells from Zurich's Cobrawagen and the Stuttgart DT8 light-rail unit
  • Vehicle parameters can be defined in the XML file
  • Takes account of vehicles with restriced bend angle