[sumo-user] Realistic routes from observation points?

[Jan Přikryl <sumo@xxxxx>]

Dear all,

my apologies if it has been discussed before, I tried to search the archives and did not find anything relevant.

For our simulation, I am pondering the possibility to switch from our old manually generated traffic to traffic generated from "observation points", in our case traffic counts at intersection detectors. The network we are working with represents a substantial part of Pilsen (CZ), it is approximately 10 x 10 kilometers in size, and contains quite a number of small streets besides the main traffic corridors. The intersection detectors are located at the main corridors.

Given the absence of turning rates and other information (I might have an outdated O/D info somewhere, but I want to avoid it, if possible), I did some experiments with flowrouter.py and routeSampler.py, with rather pathetic results, I am afraid:

* flowrouter.py seems to pick up a few random locations in the residential areas of the network, and generate traffic that goes from those places into the main corridors and then leaves the corridor to some other location; as a result, the small streets in residential areas are completely blocked by traffic as their capacity cannot handle the traffic volume

* routeSampler.py does a better job but given the necessity of supplying it with a set of random routes, it tends to pick up several "most promising" routes from a quite large route file (cca 500MB) and while the traffic at the main corridors is definitely "nicer", the result is to some extent similar to the flowrouter.py, with traffic jams in different residential areas that in my opinion are now mostly related to low capacity and unregulated / priority intersections -- while the number of vehicle sources / destination points increases, the capacity of the network in the side streets in not sufficient to accommodate the traffic.

Note that our goal is to have realistic, but not necessarily exact replication of traffic in the city. We need to simulate the whole city with public transport and we want to determine how the daily traffic affects some parts of (trolley/e)bus routes.  

I think I am doing something wrong. Is there any additional howto / cookbook / manual regarding this besides the standard documentation (https://sumo.dlr.de/docs/Demand/Routes_from_Observation_Points.html)? I am aware of Michael's paper about routeSampler.py, but it does not help much in this context, I am afraid.

I can share the network, the scripts I am using and all the other files, of course -- the only problem is that the complete dataset is BIG (230MB zipped, 2GB raw).

Thanks!

Jan

-- 
Jan Přikryl
RICE FEL UWB  & CTU FTS