Regarding jams: I don't think that there is a traffic-count mismatch. After all, the traffic counts at the intersection should be no higher than you real-world measurements. Also, by using turn-counts instead of edge-counts, a big part of the route-related ambiguity is eliminated. At least when taken in isolation, every intersection should be a close match to reality. >From my experience, there are plenty of things that can go wrong with turn lanes and lane-to-lane connections that can reduce intersection flow and create jams in a scenario that is already close to saturation. Here is a somewhat systematic approach to understanding the jams: - pick one of your intersections with lots of traffic that appears to be oversaturated (queues keep growing over multiple traffic light cycles) - create a sub-network with just this intersection and plenty of incoming edge length (to better observe growing queues) - use routeSampler to create traffic for just this intersection (it should be easy to get a perfect traffic match for a single intersection) - look at the simulation carefully, - Are all lanes used? - Is the traffic light switching reasonably? - Is the measured flow even plausible? - Are there any deadlocks? If you still cannot figure it out, send me an offending single-junction scenario at I'll check it out myself.
regards, Jakob Am So., 12. Apr. 2020 um 22:43 Uhr schrieb Jakob Erdmann < [email protected]>: > regarding public transport for a reduced network, see > https://sumo.dlr.de/docs/Tools/Routes.html#cutroutespy. > > Am Do., 9. Apr. 2020 um 06:55 Uhr schrieb Tetris < > [email protected]>: > >> Hello, >> >> 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 >> >> https://sumo.dlr.de/docs/FAQ.html#the_simulation_has_lots_of_jamsdeadlocks_what_can_i_do >> : >> >> 1. invalid network >> >> invalid lane numbers -> where can I see that the lane numbers are >> invalid? netcheck.py? But netcheck.py 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 netcheck.py? >> >> 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 routesampler.py. Can I calibrate the >> traffic counts with Cadyts or is Cadyts for different use cases? >> https://sumo.dlr.de/docs/Contributed/Cadyts.html >> >> 4. invalid routing >> only shortest path were used instead of a user assignment algorithm >> -> I >> used randomtrips.py as input for routesampler. Would it be useful to run >> duaIterate.py 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. >> >> https://sumo.dlr.de/docs/Simulation/Turnarounds.html#controlling_where_turnarounds_may_happen >> 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. >> https://elib.dlr.de/127994/1/08569938.pdf The chapter V-B"demand >> adaption" >> suggests 3 methods: Cadyts, SUMO Calibrators and REROUTER. >> Which of those 3 methods fits the best to routesampler.py output from >> random >> trips? >> >> >> >> >> >> -- >> Sent from: http://sumo-user-mailing-list.90755.n8.nabble.com/ >> _______________________________________________ >> sumo-user mailing list >> [email protected] >> To unsubscribe from this list, visit >> https://www.eclipse.org/mailman/listinfo/sumo-user >> >
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