Routing not only for Prams

Room: Auditorium A

Sunday, 11:30
Duration: 20 minutes (plus Q&A)


video on media.ccc.de


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  • Roland Olbricht

What must be mapped to make routing for prams and wheelchairs practical? Three years ago, the local meet-up in Dortmund, Germany, started a campaign to make step-free routing available for the general public.

The lessons learned mean that such routing is possible, but there is a lot missing to map - both in Dortmund and in all other parts of the world.

Map the essential where fellow mappers are sparse. And codify the full ground truth where the passion allows it. I hope to encourage mappers for the quest to get their neighbourhood ready for wheelchairs, prams and all the other pedestrians!


Routing for pedestrians is a much broader challenge than the well-known car routing. Cars all over the world are mostly uniform, but pedestrians vary widely in their capabilities. This means that a lot of details that a sportive person might not even notice can be literally a roadblocker for people with prams, for wheelchair users or simply lesser-abled people with not enough strength for a complete stairway.

Becoming a father has been a good opportunity to check in practice what is and what is not feasible for a pedestrian with a pushed vehicle. It turns out that the first step is to get aware of the various kinds of obstacles that get in the way. Beside the obvious steps and kerbs, there are impassable surfaces, too narrow or too steep sections. Or simply sidewalks missing completely on the ground.

As of now, OpenStreetMap data does not even suffice to figure out where one or both sidewalks actually exist. This puts into perspective the discussions about how to map best details of both detached ways and sidewalks. A couple of tagging approaches are compared to allow educated guesses which level of detail will allow for good results rather in weeks and months than in years or decades. I even dare to give suggestions what tagging practices we should additionally adopt to be able to map faster.

The background of this talk is an initiative from the Dortmund meet-up: For the large event Kirchentag 2019, we mapped at least the city center sufficiently well for wheelchair mapping. The whole city with its 1500 km streets has turned out to be simply too much. Given that a city with a local meet-up is in a relatively good position to be mapped, it was no surprise that also elsewhere the data is simply not yet good enough for wheelchair routing. The hope is that simple suggestions what helps is getting more traction than a sophisticated mapping hierarchy.