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Question about wrong Route / closed roads


#1

Hi,

I have a question regarding getting sometimes wrong routes.

An example can be seen here:
https://graphhopper.com/maps/?point=53.473501%2C12.43471&point=53.475053%2C12.429861&locale=de-DE&vehicle=car&weighting=fastest&elevation=true&use_miles=false&layer=Omniscale

The wanted/correct route would be somehow like this:

What is the reason that graphhopper uses the longer route? Is there a road blocked/closed or any maintenance so graphhopper ignores that road?

Thanks in advance,
Andreas


#2

There can be various reasons. In this case it is the bollard which access condition we currently cannot handle and therefor block access: http://www.openstreetmap.org/node/3555118028


#3

Ah okay, now that makes sense.

I’m going to check if there is any method to extract/remove these bollard from the .pbf file before starting Graphhopper / or just ignore bollards completely in graphhopper.

Thank you for the fast response!


#4

If the bollard is not there in the real world, you could remove it from osm. If it’s there but you can drive past it, you should set access=yes.

Best,
Robin


#5

Hi, how do you handle conditionally accessible roads like e.g. Tioga Road? (https://www.openstreetmap.org/way/520725577#map=19/37.91110/-119.25777). GraphHopper doesn’t calculate route through it in July despite the road is closed from Nov to May (expressed in parameter access:conditional no @ (Nov-May))


#6

Per default we ignore such conditional access tags (for the open source routing engine) but you can enable this.

On GraphHopper Maps it is enabled and it calculates a route if it is tagged like this in July but will fail in May:

E.g. for car we had an import problem that will be hopefully fixed tomorrow and so it currently reflects how it should be in May.


#7

Good day Peter,
is there any flag that may be used when requesting Routing API, so these parameters won’t be ignored or is it possible only on own hosting? Thanks


#8

In our open source offering we ignore them per default, but this can be configured.

In our hosted Routing API we don’t ignore them (please note that this topic is in the core category which is about the open source project). I.e. for the Routing API requesting it in summer can give different results compared to winter (which can be also ugly if you want to plan a summer tour in winter, but currently this cannot be modified up on request).