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Re: [sumo-user] Realistic Simulation with traffic data and calibration


I'm still figuring out what causes the traffic jam in the simulation. There
is no specific junction at which the traffic jam starts. It's more in
general that there are way too many vehicles. 

I'm going through the list from

1. invalid network 

    invalid lane numbers -> where can I see that the lane numbers are
invalid? But is for edges, not lanes. 

    missing turning lanes -> Does this mean turning lanes at junctions? This
is something I could check just by looking at my network. I created routes
for every turn for all the junctions in my network (at least for those that
have traffic counts)

    invalid connections -> that's checked by

    invalid junctions (big clusters of small junctions should be joined) ->
used join junction command. 

2. invalid traffic lights (see Improving generated traffic lights) -> I used
actuated traffic lights. 

3. invalid demand (too many vehicles overall, too many vehicles starting on
the same edge). -> This seems to be causing the trouble. 
I haven't defined starting edges, just the routes and maybe too many routes
start with the same edge?
The traffic demand is build upon traffic counts which have been made on
different days, even different months. Nonetheless I just put these traffic
counts into the turncounts.xml for Can I calibrate the
traffic counts with Cadyts or is Cadyts for different use cases?

4. invalid routing
    only shortest path were used instead of a user assignment algorithm -> I
used as input for routesampler. Would it be useful to run on the random trips?

    too many vehicles start/end their route with a turn-around. -> I have
seen in the simulation that vehicles turn around at the end of the road
where the network ends.
I could use one of the --no-turnarounds options in netconvert. 

5. invalid insertion (vehicles being inserted on the wrong lane close to the
end of an edge where they need to change to another turn lane). This can be
fixed by setting the vehicle attribute departLane="best" -> I already
updated my rou.xml and inserted departLane="best" to every vehicle. 

I think the main cause of the traffic jam are the traffic counts that don't
fit together. The chapter V-B"demand adaption"
suggests 3 methods: Cadyts, SUMO Calibrators and REROUTER. 
Which of those 3 methods fits the best to output from random

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