I have a student project running where we want to include speed limits into a map of our local region Thy here in Jutland Denmark. Can we include speed limit data into opernStreetMap? I have today received a gps receiver that delivers NMEA 0183 data to my pc. I was able to monitor position on Google maps via an application - but no speed limits available. Can NMEA messages from a gps receiver be integrated into OpenStreetMap? asked 16 Apr '13, 12:42 SteenOluf |
As Ed and Vincent write you can add speed limits to OSM (and we do have some, but not many in Thy) and a GPS tracker can be useful for mapping, but from your question I guess you want to know more about how everything actually works. To answer that I suggest you start with Learn OSM and then send a message to the talk-dk mailing list with a more detailed description of what you want to achieve with the project and what skills you have available. Then it will be much easier to answer if the data from Geodatastyrelsen is more useful (probably not), how/if GPS traces can be used and what existing tools/frameworks can be useful for your project. This and all the other followup questions you and your students will have is probably more suitable for the mailing list, but if you are impatient, you can try the Danish IRC channel. answered 16 Apr '13, 17:06 Dymo12 |
Speed limits can be added to an osm way using the maxspeed tag. GPS are commonly used to get a "trace" of position data to help maping in OSM. Wether you collect that data using NMEA frames or using a gpx file doesn't matter much (except the gpx file is more practical). However, you cannot use the nmea frames to gather the speed limit:
You could look at which speed you were driving to infer the maxspeed, but that's very unreliable. Best thing is to survey the speed limit signs, using a camera for example. answered 16 Apr '13, 14:25 Vincent de P... ♦ |
This is really two questions I think. The page you want to see about adding speed limits is Key:maxspeed and roads already tagged can be reviewed on this map (I believe others are also available). I don't know the answer to your NMEA question - if it is speed related won't it contain the speed you were actually going rather than the speed limit? The NMEA wiki page suggests traces can be opened in JOSM though, if that helps. answered 16 Apr '13, 14:19 EdLoach ♦ |
Thank you for these informative responses. We checked Geodatastyrelsen and their maps are not editable for us - we can't access the editor they use. We decided to go with OpenStreetMap! We now use the JOSM editor to create a layer where we can enter roads as polygons. Q1: Should we enter separate layers for 50,60, 80 and 90 km/hour? Q2:With a gps trace on the map with speed data encapsulated - how do we compare the position with the road polygons and then check the speed against the speed limit? Q3: Is there an editor available for our own programming so we can do the task of Q2?
Please create a separate question for each topic, and reexplain there what you are trying to do (I can guess but it is hazy).