Steve, I've seen this problem a long time ago when I was using some software to convert a track I had previously made from live data, I think using UPSUtility. I got a similar 50 to 100m parallel error. I think it turned out to be a conversion error between the OSGB or possibly UTM format that UPSUtility was set up to use at the time and the WGS84 of the final output required for the gpx file. The track predated OSM (one was from the opening day of the M6Toll) so had been saved in GPSUtilities format.
Converting the track within GPSUtility before then saving as a gpx I think finally fixed the problem, but it was too long ago now to be sure exactly what I did. Cheers Andy >-----Original Message----- >From: [EMAIL PROTECTED] [mailto:talk- >[EMAIL PROTECTED] On Behalf Of Steve Hill >Sent: 06 May 2008 10:41 AM >To: [email protected] >Subject: [OSM-talk] Track offsets > > >I've come across a problem with one of my methods of collecting tracks - >I'm hoping someone might have some input: > >I've got a computer in my car which connects to my (old style) eTrex >Venture GPS via a serial cable. The computer runs gpsd to talk to the >GPS. It also runs Kismet which does things like logging 802.11 networks, >but most importantly Kismet talks to gpsd and logs the GPS track. I then >process the .gps file Kismet produces into a GPX file to use with OSM. > >Now the problem - I recently compared the track downloaded from the GPS >itself (using gpsbabel) with the track produced by Kismet and found they >were fairly consistently offset from eachother by 100m or so. I haven't >worked out where this error is being introduced yet, but the GPS is set to >WGS84 so I would expect the NMEA stream and the GPS's tracklog to match. > >My next step is to look at the NMEA stream itself and see if that is >correct, but has anyone else here had any similar problems that could >shead some light onto what is going on? > > - Steve > xmpp:[EMAIL PROTECTED] sip:[EMAIL PROTECTED] >http://www.nexusuk.org/ > > Servatis a periculum, servatis a maleficum - Whisper, Evanescence > > >_______________________________________________ >talk mailing list >[email protected] >http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk _______________________________________________ talk mailing list [email protected] http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk
