I'm setting up a tracking and navigation system for the trucks at work. They've each got a tablet PC (running Windows unfortunately, because of needing MS Access), with a built-in GPS and 3G modem.

So far, the track logging is working, as is the uploading of that data to a central server. The tracks are created continuously, as fast as they can be read off the COM port, and split up into hourly log files.

These tracks are converted to GPX files on the server, and from there will be uploaded to OSM.

Is this an okay approach? We'll end up with buckets of data about regional WA, including fire tracks, power poles, etc. But should I do anything else to prepare it?

The idea is that, once the data's back in from the trucks, I'll trace the tracks and add whatever other data I can (there's photos coming in too).

Location: Fremantle, City of Fremantle, Western Australia, Australia

Comment from Rhubarb on 10 February 2010 at 12:52

Sounds like a great idea to me :)
The only suggestion that I may make is to process the gpx tracks with gpsbabel to simplify the tracks a bit. I don't the load of having to have 1sec interval samples for such big tracks would be good for OSM's servers.
So I'd suggest to simplify the tracks somewhat before uploading them to OSM.
And keep the original detailed tracks for yourself (or others if they request) to do the tracing.

I'm sure I could think of more stuff, but it's late and I should be asleep :P

Comment from JohnSmith on 10 February 2010 at 12:58

Apart from Rhubarb's comment, I wouldn't use a personal account to upload all the track data, make a new "bot" account...

Comment from Sam Wilson on 10 February 2010 at 14:18

Hmm, yes, good idea about rationalising the tracks; does gpsbabel do that by default? That's what I'm using to convert to GPX anyway.

And John, is there anything special about a bot account, or is it just a normal one with bottish tendencies? :-) I'll create one.

Thanks for your input!

Comment from Jean-Marc Liotier on 10 February 2010 at 14:26

The "bot" account is a normal account - it just lets you isolate those bulk entries from your personal contributions.

Getting GPS logs from large fleets is a wonderful opportunity - I'm thinking about how to evangelize them about it...

Comment from Jekader on 10 February 2010 at 22:56

That's a really great idea!
Yes, a bot account would be reasonable to separate the bulk imports from your personal work. On the other hand, I don't think you should bother simplifying the tracks. NORC donated 30 Gb (!) of tracks, and nobody died so far :)

Wish I had a fleet of trucks to put GPS loggers on :)

Comment from FOSS on 11 February 2010 at 02:43

Get an OK from your BOSS'es. We dont want your employer to create problems for OSM later.

Comment from Jekader on 11 February 2010 at 10:21

I don't know what problems they can make to OSM - just tell you to delete the tracks in the worst case. But I agree you should tell them about your plans in the fisrt case.

Probably you've already gotten an approval from them. If not - I think it's easy to get. First of all you're helping a free project. Second, you're not uploading confidential data (if you upload the tracks as public - noone will be able to see the timestamps on trackpoints, so it won't be possible to get the speed/route from the track), and third - you can also promote your company, if they'd like that - you can name the bot after the company, or write their name in the bot's description page :)

Oh, and now I've thought of a GPX optimisation variant - to remove the points, where speed is less than, say, 3 km/h - so that when a truck stays without a movement for an hour, we don't get 3600 points with the same coordinates. Don't know how to do this optimisation, but a simple script should be enough, I think.

Comment from Sam Wilson on 11 February 2010 at 11:55

Yes, I'm certainly trying to get written approval, but it's not hard to put the case: the trucks drive around, and if we submit the tracks (so my pitch goes) then the maps that they use to drive around will get better, and the trucks can drive around some more. See, often people (in my company) are in out-of-the-way places, and need to tell other people how to get to the same out-of-the-way places in a couple of weeks. Thus, they draw a map! This way (i.e. using OSM), they don't have to draw all the map. Understandable even by people who don't really get the whole Free thing! :-)

As for removing the puddles of points created by standstill vehicles: does anyone have any good pointers about how to do that? All of the processing so far is using bash scripts, so it'd be nice to keep things simple.

Comment from Jekader on 11 February 2010 at 19:01

That's even better, if OSM maps are used by your company!

About the optimizer - I think you could use some XSLT ruleset to do the job. Or you could ask the guys working on OSM code to implement an optimizer for all the tracks, uploaded to OSM - I think that would be a useful option!

Comment from Dwi Secundus on 13 February 2010 at 20:53

Re simplifying tracks: This is not necessary in my opinion. The more detailed they are, the better!

Comment from Sam Wilson on 14 February 2010 at 00:28

Perhaps simplification is the wrong word -- have a look at the northern end of at the big tangled mess over a house. There are dozens of points all right near each other because the GPS was sitting still in a room for a couple of hours, dutifully logging away. This would be a common occurence in a vehicle.

Perhaps error removal is really what needs to be done to these tracks. However, I don't know if the extra data volume is actually of concern, and I don't really know how to ''quickly'' edit the tracks, so for now I won't make any changes.

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