generated on 2019-08-22 00:08:53.785232 from the wiki page for Simulation/OppositeDirectionDriving for SUMO git


This page describes simulations which are enabled for for overtaking through the opposite-direction edge. To enable this feature, the network must contain additional information regarding the adjacency of opposite-direction edges.

Building a Network for opposite-direction-driving

The enable overtaking through the opposite direction lane, the .net.xml file must contain <neigh> elements that specify adjacency. The options for including this information are described below.


By setting the NETCONVERT option --opposites.guess <BOOL>, opposite edges are identified heuristically.


Adjacency can be declared explicitly in an .edg.xml file as described here. Explicity definitions take precedence over heuristic computation of adjacency.

Model Description

Vehicles may overtake through the opposite direction lane to improve their travel speed. The decision to perform such a maneuver is subject to additional checks in regard to

  • oncoming vehicles
  • the assumed duration for overtaking the leading vehicle(s)
  • the presence of free space at the end of the column being overtaken (maximum look-ahead is currently fixed at 150m and overtaking may only take place if free space is found before that threshold).
  • the priority of intersections that may be passed during overtaking (only straight prioritized links may be used for opposite-direction overtaking)
  • The required safety-buffers can be calibrated using the vehicle type attribute lcOpposite


  • Opposite-direction-driving is not yet compatible with the sublane model.
  • Visibility of oncoming traffic and the preceding vehicles due to road topology and occluding vehicles is not taken into account.
  • Neighboring lane information can only be set if both edges have the same length. As a workaround the length of the edges may be set to a custom value (which may be different from the geometrical length). This can be automated by setting the option --opposites.guess.fix-lengths.