How to get position data for subway lines?

Dear all,

I would like to know what I can do to get the position data for subway.
I’m living in Beijing and there are several new subway lines which are not in Openstreetmap.

Some old lines are available in such a good quality that you can see switches and sidetracks.

If there would be an easy way to get the position data (with my Android phone), I would like to add the new line 14.

Maybe somebody has an idea.
Thanks in advance

Georg

Quite yesterday there was a similar question:

see http://forum.openstreetmap.org/viewtopic.php?id=30136 and tell us when you get stuck in detail. Tell us then also what you have tried so far in detail.

Hi stephan75,

thank you for your answer. I think there is a little misunderstanding.
I don’t want to download these kind of information from OSM, I want to enter new information for OSM.

The problem is that I don’t know how to record such position data when I don’t have GPS. What I need is a source. The only useful source in my eyes would be map.baidu.com but it’s not allowed to use that material, as far as I know.
Any other ideas?

One time-consuming way is just go to each station, take a picture of the station’s exit map, and then go through the exit to determine its location (you can go through all exits if you have time). Afterwards, its easy to determine the accurate location of the station, and as a bonus you can also map the exits (with railway = subway_entrance).

Another way is to use public knowledge, for example a friend tells you that new subway station X is located at the intersection of streets Y and Z. This intersection is likely to be found in the existing OSM data so the station can be added. Sometimes Wikipedia has the station’s coordinates.

Copyright issues are murky: what exactly is public information and what is copyrighted material? Just make sure that you don’t make exact copies of other maps.

Have you read http://wiki.openstreetmap.org/wiki/WikiProject_China#Legality ? In that environment, mapping information that is not obvious on the ground or from freely available aerial photographs might be particularly unwise.

Even 百度 have used some fairly obvious straight line approximations, and you may find that their routes are topologically correct but are approximations based on the fact that most lines seem to follow the roads (cut and cover construction?). The 百度 routing of the track through 奥林匹克森林公园 shows such obvious approximations. http://j.map.baidu.com/qAFK4