Strava: Routing Errors

[planemad]

Edit: continued on #114

Strava is a popular fitness app used by runners and cyclists throughout the world. They recently switched to OSM and have released the probe data for use to improve the map

Task http://labs.strava.com/routing-errors/#10000000/9/-122.62390/37.78483

• Trace/realign missing roads and footways on the map
• Work only on the automatically detected errors where there is significant Strava activity and no map data. Hide the user reported errors.

Task coverage

• SF Bay Area, USA done
• USA

Mapping source

• Strava Walking http://globalheat.strava.com/tiles/walking/color5/{zoom}/{x}/{y}.png
• Strava Cycling http://globalheat.strava.com/tiles/cycling/color3/{zoom}/{x}/{y}.png
• Bing
• Mapbox Satellite

Timeline

• Starting 08/19 @mapbox/india-office will work on this full time with a weekly progress summary

Instructions

• The Strava tool is similar to to-fix
• Load an error point into JOSM
• Activate the globalheat imagery to see where users have been walking/cycling
• Compare OSM data with Bing/Strava imagery to find missing areas to trace
• Tag the feature appropriately
• Skip issues where there is an existing parallel road feature. This would indicate a missing cycle lane or a footpath. Priority is on adding completely new paths not in the data.
  

Features

• highway=*
• cycleway=*

Tips

• Use realign tool (w) to quickly improve existing ways
  

cc @mapbox/team-data

[pratikyadav]

At some places, I found a series of errors.

Found that there was a cycle lane on right side and the tag cycleway:right=lane was missing.

[talllguy]

I've been working on these for a while using their Slide tool (a fork of iD) to autosmooth paths. Cool to see the MB data team on the case, because the Strava user community seems pretty vocally negative about the switch to OSM.

[planemad]

False positive: Cycle lane tags are not detected

Looks like Strava is doing a comparison purely between the activity centerline and OSM geometries and ignoring cycleway/sidewalk tags.

This results in false positives where a road has already been tagged with a cycleway=* (purple dash) but an issue is generated because the activity centerline is more than 5m from the road geometry. An example is at this junction in Palo Alto where the data is correct. There is no improvement to be made to OSM in these cases. Mark as fixed.

cc @mapbox/team-data

[planemad]

@tallguy thank you 🍻
Its still a vocal minority who's making all the noise. Would be interesting if Strava offered premium accounts to those who made more map fixes.. 💭

[talllguy]

@planemad that sure would create some incentive. Though agreeably it is the internet people who are making the most fuss.

Regarding _false positives_, I've come across quite a few that I can share here.

• Ferry routes: as seen in this tweet ferry routes are not currently routable in the Strava engine.
• Certain routes that are trunk or motorway seem to disallow routing despite the tagging that bikes are allowed. I'm not sure if that has been fixed, but it was an issue before. In many US states, bicycles are prohibited from trunk and motorway roads.
• +1 on your sidewalk point
• Paths on abandoned railroads: There are many cases where a railroad-fan mapper added an abandoned railroad to the map, but it is now a bike path. These should (probably) have their tagging preserved, but be changed to a highway=path or whatever is most applicable.

Finally, Dr. @paulmach from Strava presented about the slide tool and is knowledgeable about the routing engine.

[talllguy]

Forgot to mention that it looks like in that JOSM screenshot that the Willow Road might be tagged as a trunk, thus running into my issue above.

[ramyaragupathy]

Here is an update on the number of nodes and ways updated by the team based on Strava feedback in the Bay Area since 08/19

User	Nodes	Ways
PlaneMad	1255	33
pratikyadav	3789	206
ramyaragupathy	460	20
Chetan_Gowda	6211	60
jinalfoflia	29	1
aarthy	267	11
	12011	331

cc @lxbarth @planemad

[planemad]

False positive: Inaccurate traces in wooded areas

In thickly wooded areas like this, inaccurate GPS traces is being detected as a missing path. Mark as fixed.

cc @mapbox/team-data

[planemad]

• Over 2 days @mapbox/india-office has cleaned out all the automatically detected issues in the Bay Area.
  
• Team will continue to hit other high activity zones the coming week: NE corridor, LA
  
• The Strava API has a limitation to load only 200 points in one request. If there is a possibility to get a full dump, we can easily load all the tasks into to-fix in one go for a full cleanup @paulmach

[planemad]

Task Update

@mapbox/india-office will focus on clearing automatically detected routing errors in the following high activity regions:

• Boston - NYC - Baltimore - DC
  
  
  
• LA - San Diego
  
  
• Vancouver - Seattle - Portland
• Denver
• Madison - Chicago
• Minneapolis
• Toronto

[planemad]

Remaining issues loaded into to-fix, closing here. Continued on #114