ETA computation in urban areas with OSM data: what is the urban trigger?
  • Vote Up0Vote Down shlublushlublu
    Hi,

    When I use MFN in Paris, the calculated ETA doesn't take the urban speed settings of my vehicle into account. It takes the non urban setting instead.
    However, when I use MFN in Bangkok, these urban speed settings are taken into account and work perfectly.

    I'm using OSM data, so I guess this is related to a specific tag of the area. 
    Would you tell me more about what triggers the urban/not urban ETA calculation?
  • 36 Comments sorted by
  • Vote Up2Vote Down hvdwolfhvdwolf
    Hi, 

    All those changes are actually work-arounds for the underlying problem: Navigator does not use speed penalties for cross-roads, intersections, traffic lights, traffic-calming options (bumps, measures around schools, s-curves in roads to slow down traffic). 
    Some/most other nav apps do take these "obstacles" into account and can therefore calculate much better "in city" traffic times. It sometimes even does change the correctness of the route. Because when these speed penalties would be taken into account, another (slightly longer?) faster route might be calcuted routing over streets with less of these "obstacles".

    (And I'm not better: I do use (have to use) the same work-arounds)
  • Vote Up1Vote Down NigelNigel
    Hello,

    We are testing new script that will try to set urban flag to every city/town/village. It has something to do with built_up areas, city_centers and buildings, we ignore admin level boundaries because in a lot of cases it's bigger then actual city/village. It will change average speed if there is no speed_limit set in OSM. We are still in testing phase and script should be working now in Czech, partly in Germany. We need some feedback for now because there can be some problems with for example highways in a city where you can go 130 but that is not set in OSM. Which would change the routing badly.
    If you change the urban speed in settings now it won't have any effect because urban flag is not set properly. If you do it in Czech it will rewrite every speed set with urban flag.(this is what you want).

    Please tell us if you want to include your country to the "testing" list or if you know about some problems that could occur in your country.

    There are some information as well.
  • Vote Up1Vote Down NigelNigel
    There will be some fixes next month, so we would like to test them first on fewer countries. After that we plan to make them global.(I will add Danish map to next month "urban script" so there is more testing ground, reviews after that are appreciated).
  • Vote Up0Vote Down tomastomas
    may be speed attributes in Paris are missing in free maps?
  • Vote Up0Vote Down shlublushlublu
    The legal speed limits are properly documented. What I'm wondering is what makes MFN determine that we are in a urban area (or street?) when navigating, and thus makes the urban settings of the vehicle to apply instead of the non urban.

    If you could tell me what triggers this, I'll check OSM and fix whatever needs to be.

    Thanks!
  • Vote Up0Vote Down tomastomas
    not sure, but I think it is built up areas
    it could be something else too
  • Vote Up0Vote Down hvdwolfhvdwolf
    I would think it is based on admin boundaries.
  • Vote Up0Vote Down shlublushlublu
    Bangkok has an admin level level 4 where Paris has an admin level 8. This is the only relevant difference I have seen, and it sounds unrelated.

    Otherwise, both have boundary=administrative and type=boundary set. Bangkok has capital=yes set, Paris doesn't, but being a capital is not the only thing that makes a city urban... (some may think that it would be a valid trigger though :) )

    Would it be possible to ask the developers what the trigger is? 
  • Vote Up0Vote Down IU0BMPIU0BMP
    <<< When I use MFN in Paris, the calculated ETA doesn't take the urban speed settings of my vehicle into account. It takes the non urban setting instead. >>>

    It's the same in Rome.
  • Vote Up0Vote Down OldieOldie
    That is the same everywhere. There are many posts in this forum already complaining that it is very difficult if not impossible to get to your destination in urban areas at the time MFN has calculated.

    I experienced this just on Saturday evening coming home to Chemnitz from a beautiful concert of Patty Smith (Horses tour) in Dresden. As long as I could match the max speed of  50/30 km/h (or 10 % above),  I could keep the calculated time. That was for the first four or five km within the Chemnitz' urban area,. But there were nearly no other vehicles on the roads and trafic lights were switched off for the night. Only on the last two to three km, where I had to stop on some trafic lights, I "lost" nearly five minutes.
  • Vote Up0Vote Down shlublushlublu
    Hello @Nigel

    Thanks for this detailed feedback and link.
    Yes, I think including France would be a good idea. I don't remember in which part of the MFN map of France is Paris, but we may want to limit the test to this one for the time being.

    There's just one thing I'm not sure I understood properly. 
    You said " It will change average speed if there is no speed_limit set in OSM". To my understanding, this means that roads with a speed limit set in OSM won't benefit of the urban/non-urban setting of the vehicle? I'm asking because this is where the issue resides: often, in urban areas, you drive way slower than the official limit due to traffic jams, lights, etc.

  • Vote Up0Vote Down NigelNigel
    If you change vehicle setting in urban areas it will change all roads with urban flag. So that should work just fine(with new script applied). It will still use the speed_limit in default behaviour though. There is unfortunately no average_speed tag in OSM that we can use(or am i wrong?).
  • Vote Up0Vote Down shlublushlublu
    Thanks for this @Nigel.

    So for example, if my vehicle setting is, for a given type of road, is 90Km/h non urban and 20Km/h urban, 20 Km/h will be applied to compute the ETA in urban areas even if this road is actually limited to 50Km/h in the city I'm driving in?
    If so, that's great, exactly what I need.

    And you are right, there's no average speed in OSM, currently. This is being discussed but really hard to maintain: http://wiki.openstreetmap.org/wiki/Routing#Average_speed
  • Vote Up0Vote Down NigelNigel
    Yes, that should work. There is a good chance we will add France(with Paris) in the next OSM conversion(15_09). 
  • Vote Up0Vote Down shlublushlublu
    Great, looking forward to testing that!
  • Vote Up0Vote Down shlublushlublu
    Hi @Nigel,

    I have given a try on the latest release of the map, with Navigator 15 (PC) and on the Android app. Unfortunately, it doesn't seem to work. The displayed ETA corresponds to my non-urban settings.

    Was this integrated to the map released on the 29/09?

    Thanks!
  • Vote Up0Vote Down NigelNigel
    Hi @shlublu, 

    New OSM maps 2015_11, will have France,Belarus and Italy included in The Urban testing. I'm sorry any earlier maps don't have urban marked. I apologize for this since it's probably my fault. Please wait a little longer.
  • Vote Up0Vote Down shlublushlublu
    Hi @Nigel,
    No problem at all! And thanks a lot!

  • Vote Up0Vote Down varjatvarjat
    +1 ;-)
  • Vote Up0Vote Down shlublushlublu
    Hi @Nigel,

    I've just updated my maps. Looks like it works in Paris! I didn't yet do an actual journey but I computed a few directions. The given ETA are way more realistic than they use to be: 50 minutes to reach the center of Paris from the east sounds good for example, way better than the 10 minutes I used to have.

    I'll give a try in real conditions and let you know.

    Great anyway, thanks !
  • Vote Up0Vote Down NigelNigel
    Good to hear. Don't be afraid to post any examples where it behaves incorrectly because that's exactly what I need :).

    You can also try to set urban settings to very high speeds in order to use only map data. The default speed of streets in urban should be lower then non-urban.

    Thanks.
  • Vote Up0Vote Down IU0BMPIU0BMP
    <<<You can also try to set urban settings to very high speeds in order to use only map data>>>
    This sounds like MFN takes into account the lowest value between the speed entered by the user and map data.

    Well, I made some simulations in Rome with urban and non-urban routes and the results are good.
    =D>
  • Vote Up0Vote Down shlublushlublu
    I just tried a way/return from Paris to Creil, near Beauvais. ETA says 3:40 for the way, which sound a bit enormous (this is actually 45' once outside Paris, so 1'30 overall probably). It seems that the area considered urban covers non urban areas. 

    Do you need my vehicle settings? (I tried to add them here but this makes the post too long)

    EDIT: I could make the things way better for both urban and mixed-urban-and-non-urban journeys by editing my vehicle settings. I still think urban-flagged areas exceed actually urban areas though. 
  • Vote Up0Vote Down NigelNigel
    Yes that can happen as well. If you send me a coordinates of start and end I can look into it. You can post vehicle settings as well.
  • Vote Up0Vote Down shlublushlublu
    Sure,

    From: 48°51'51.5"N / 2°20'38.0"E (Center of Paris)
    To: 48°06'10.6"N / 1°39'49.3"W (Center of Rennes)
    ETA: 7h36m (should be something in between 4h30 to 5h30 with my settings)

    Settings:

    - type: Car
    - speed limit: 140
    - optimization: fastest-transit
    - 0: extra-urban: 110 / urban: 75 / pref: 50
    - 1: extra-urban: 90 / urban: 20 / pref: 50
    - 2: extra-urban: 90 / urban: 15 / pref: 50
    - 3: extra-urban: 90 / urban: 10 / pref: 50
    - 4: extra-urban: 80 / urban: 10 / pref: 50
    - 5: extra-urban: 80 / urban: 10 / pref: 50
    - 6: extra-urban: 50 / urban: 10 / pref: 50
    - 7: extra-urban: 50 / urban: 10 / pref: 50
    - 8: extra-urban: 15 / urban: 15 / pref: 50
    - 9: extra-urban: 60 / urban: 60 / pref: 50
    - 10: extra-urban: 50 / urban: 8 / pref: -50
    - blocked penalty: 20000

  • Vote Up0Vote Down NigelNigel
    Can you tell me where do you expect to be out of urban? I can look how accurate the script is in this example. You are also ignoring the osm speedlimits(with this setting) in urban areas which is unfortunate but understandable. (I feel like there should be setting for traffic where you would set 70% and all speeds would be lower by that value.)
  • Vote Up0Vote Down OldieOldie
    I think I wrote it already somewhere in this forum, but I did not look where. Until a couple of days ago I used my own speed settings as those from @shlubu, just not as drastic the reduction of urban speed (down to 15to18). Until I found out on one route, that what was more realistic earlier became much to long on one day. So I switched to a new car profile with preset settings of Navigator and all of a sudden, it was the standard setting of Navigator, that was more realistic than my individual setting earlier.

    So I think know, that @shlubu should try to switch to standard settings and see what results he gets.
  • Vote Up0Vote Down shlublushlublu
    Hi Nigel,

    It's difficult to answer as my thoughts are only based on the result.

    Before the new map to be released, I was using another setting that was slower on non-urban area to statistically absorb the time lost in urban areas. It was working OK with long haul travels, but of course not with short ones: in cities the ETA was too optimistic and in the countryside it was pessimistic. 

    Now, I use the values that I can observe when driving (or that I think I observe, which is different as it might be unaccurate). However, this works relly fine inside Paris for example. However, the final result is really pessimistic on long haul trips while the non-urban areas are "faster" than they use to.

    This to say that I couldn't yet determine where time is lost. This is just something I infer.

    Maybe my approach is not right though. I just don't see how to do otherwise. 

    Regarding the <speed_restrictions> tag, they are all set to "yes", I forgot to mention that sorry.
  • Vote Up0Vote Down shlublushlublu
    Oh thanks @Oldie ! I'm gonna give a try and report !

    EDIT: I switched to the original settings and tried two trips:

    - The same as above, from Paris to Rennes: roughly 3h20, which is very optimistic 
    - Paris from east to center (the one I tried before to qualify that in cities the new map works great): 6 minutes, which would be lovely but far from the 30/40 minutes to expect in usual conditions. (and even compared to the 15 minutes it takes at 3AM)

    But there must be middle ground. If only I could determine the extent of the areas considered as urban.
  • Vote Up0Vote Down shlublushlublu
    Hey, I finally end up with a nice setting that gives a proper average whatever the trip is. Of course, extremes are extremes, so if there's *nobody* or if it's crowded the ETA is wrong. But as an average it is fine.

    Anyway, regardless my settings, it is much much better with your trick than without @Nigel !
    To me this should be extended to all countries.
  • Vote Up0Vote Down IU0BMPIU0BMP
    Are you using the same settings you posted in December?
    - type: Car
    - speed limit: 140
    - optimization: fastest-transit
    - 0: extra-urban: 110 / urban: 75 / pref: 50
    - 1: extra-urban: 90 / urban: 20 / pref: 50
    - 2: extra-urban: 90 / urban: 15 / pref: 50
    - 3: extra-urban: 90 / urban: 10 / pref: 50
    - 4: extra-urban: 80 / urban: 10 / pref: 50
    - 5: extra-urban: 80 / urban: 10 / pref: 50
    - 6: extra-urban: 50 / urban: 10 / pref: 50
    - 7: extra-urban: 50 / urban: 10 / pref: 50
    - 8: extra-urban: 15 / urban: 15 / pref: 50
    - 9: extra-urban: 60 / urban: 60 / pref: 50
    - 10: extra-urban: 50 / urban: 8 / pref: -50
    - blocked penalty: 20000

    or did you find better settings? It seems like Rome is not too different from Paris, despite your subways that are a lot better than ours :)
  • Vote Up0Vote Down shlublushlublu
    Hi @IU0BMP !

    I updated my settings slightly as they became a bit too extreme with the revised maps. They are available here: http://www.shlublu.org/tmp/car.xml

    This file does just contain the excerpt corresponding to my car, so it cannot be used as a standalone file: it's content should be inserted as a new <set> to the Navigator's vehicles' profile file.

    Should you give a try, please let me know how it works for you and whether you can see enhancements to bring it!

    (Your highways aren't bad, by the way! I recently made Sanremo->Mont Blanc, that was more than okay!)

    +1 :)
  • Vote Up0Vote Down IU0BMPIU0BMP
    Shlublu, I imported your set into my vehicle profiles file and I can use your settings. I can see how you updated them and they are still 'more extreme' than mine regarding urban speeds. I chose slightly higher values because I drive my car mostly on weekends when there is less traffic.

    From Monday to Friday, I go to work using public transport (subway and local train) and I never drive my car..

    One should use a weekdays profile and a weekend profile :)

  • Vote Up0Vote Down OldieOldie
    And british weekday/weekend profiles and continental weekday/weekend profiles ...
  • Vote Up0Vote Down tvotvo
    Have you planned to introduce the ”urban flag” in the map for other countries than the few you have had for month. I am especially interested in the Danish map.
  • Vote Up0Vote Down hurdygurdymanhurdygurdyman
    Please mind about tunnels under urban areas, where urban flag shouldn't be used. At westside of Como Lake there are a lot of them with maxspeed 60 km/h or more you could use to test.
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