SUMO - simulating traffic scenario

Question

How can I simulate continuous traffic flow from historical data which consists of: 1. Vehicle ID; 2. Speed; 3. Coordinates

without knowing the routes of each vehicle ID.

Answer 1

This is a commonly asked questions but probably hasn't been answered here before. Unfortunately the answer largely depends on the quality of your input data mainly on the frequency / distance of your location updates (it would be also helpful if there is a time stamp to each datum) and how precise the locations fit your street network. In the best case there is a location update on each edge of the route in the street network and you can simply read off the route by mapping the location to the street. This mapping can be done using the python sumolib coming with sumo:

import sumolib 
net = sumolib.net.readNet("myNet.net.xml")
route = []
radius = 1
for x, y in coordinates:
    minDist, minEdge = min([(dist, edge) for edge, dist in net.getNeighboringEdges(x_coordinate, y_coordinate, radius)])
    if len(route) == 0 or route[-1] != minEdge.getID():
        route.append(minEdge.getID())

See also http://sumo.dlr.de/wiki/Tools/Sumolib#locate_nearby_edges_based_on_the_geo-coordinate for additional geo conversion.

This will fail when there is an edge in the route which did not get hit by a data point or if you have a mismatch (for instance matching an edge which goes in the "wrong" direction). In the former case you can easily repair the route using sumo's duarouter.

> duarouter -n myNet.net.xml -r myRoutesWithGaps.rou.xml -o myRepairedRoutes.rou.xml --repair

The latter case is considerably harder both to detect and to repair because it largely depends on your definition of a wrong edge. There are almost clear cases like hitting suddenly the opposite direction (which still can happen in real traffic) and a lot of small detours which are hard to decide and deserve a separate answer.

Since you are asking for continuous input you may also be interested in doing this live with TraCI and in this FAQ on constant input flow.