[OSM-newbies] GPS inaccuracy

Paul Johnson baloo at ursamundi.org
Tue Jun 9 19:53:26 BST 2009


David Read wrote:

> Is this because I have a rubbish GPS receiver or could it be that the buildings of Islington are causing sufficient reflection/disturbance to the signal?

I get similar wandering paths by bicycle.  It could be a matter of
placement.  From my experience, you can put your GPS on your handlebars,
which puts the receiver in a spot where it can get the best signal, or
you can live with it.

Right now, I don't have a bicycle mount for my satnav yet, so I put it
in the key pouch of my pannier (and leave my keys in my pocket).  When I
work on the GPX, I convert the track to OSM, split out and delete the
clearly wayward segments based on aerial photography, and let the rest
fly.  This is a LOT easier to do if your GPS happens to record HDOP in
data in the GPX (since you can then color-code the GPX by HDOP and
discard anything that the GPS doesn't indicate is close to reality).

The metal on the bicycle itself (given the pannier's low-slung position
next to the rear wheel), trees overhead, and vehicles passing closely on
the pannier (right) side of the bike tend to be the biggest factors in
terms of reflectivity, and it does seem to be reflectivity causing the
problem for me.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 260 bytes
Desc: OpenPGP digital signature
URL: <http://lists.openstreetmap.org/pipermail/newbies/attachments/20090609/08d40415/attachment.pgp>


More information about the newbies mailing list