Map Matching creates unnecessary U-turns

borko · September 19, 2016, 12:33pm

Hello,
I’m using Self-hosting GH map matching for my needs.
Using master branch, check-outed these commits:

I’m trying to match my routes but get issues on some segments where matched path actually do unnecessary U-turns:

Also, with another route:

Are there any configuration params which could be adjusted to avoid these “unnecessary U-turns” ?

Thanks

karussell · September 19, 2016, 1:30pm

Can you try a bigger value for gps_accuracy?

borko · September 26, 2016, 7:18am

Hi Peter,

here are screenshots for various values of gps_accuracy:

gps_accuracy=50: (same as from my previous comment)

gps_accuracy=60:

gps_accuracy=70:

gps_accuracy=80:

gps_accuracy=90:

gps_accuracy=100:

values 60 and 90 fixed case 1 but not case 2 also.

karussell · September 26, 2016, 7:32am

Thanks, we’ll have to debug this. Maybe you would have some time ?

This is important to get fixed and worth a new issue: https://github.com/graphhopper/map-matching/issues/70

karussell · December 28, 2016, 1:20pm

Can you try with the latest development version? This should be improved.

sangxiangning · November 27, 2018, 7:53am

I’ve tried the latest development version, and it still creates unnecessary u-turns.