GPS accuracy query...

major_clanger · Occasional Visitor Joined: May 23, 2004 Posts: 10

First off - thanks to Darren et al for all the guidance given to me on this site - thanks to you I now have my GPS and TomTom kit all set up Thumbs Up

One strange query - having been out to test the TomTom (as you do :D ) it has performed brilliantly ... with one exception....

Whenever I'm driving the GPS location seems reasonably accurate. However, when I get home - the TomTom map show me to be about 100 yards away from where I am. Is there any way in which I can "reset" this to show the correct location?

Cheers

MC

major_clanger · Occasional Visitor Joined: May 23, 2004 Posts: 10

Update...

I've changed my mind - the GPS is (I think) fine, but the map is wrong!

The road to my house is (it appears) longer on the map than in reality. So, when I turn off to my house the GPS believes I'm turning onto the Green in front of the house. This causes another problem - when I set off in the car, the TomTom software has "GPS location unreliable" because (I suppose) it places me on the Green rather than on a road.

Is this possible, and if so, is there anything I can do about it?

Confused of Shropshire Mr. Green

DavidW · Posted: Sun Jun 13, 2004 12:39 am Post subject:

It's possible there's some inaccuracy in the map. TomTom does 'snap to road' to try to deal with GPS inaccuracy (your GPS position can be some way from your true position), which it does in an intelligent way when routing (as a passenger, watch what happens when the driver takes a different exit from a roundabout to the one suggested - it will often nose down the suggested exit, then realise you didn't got that way after all).

If there's a map error, all you can do is report it to TeleAtlas - I don't have the link on this computer, but hopefully someone will post it. Before reporting a map error, though, get used to how Navigator normally behaves - you may be reporting an error that's more a function of the way the system works.

The "GPS location unreliable" when you drive off is likely because you haven't given the system enough time to get a position fix. This can take a little while.

David

major_clanger · Occasional Visitor Joined: May 23, 2004 Posts: 10

David - thanks for the reply - I shall see how it goes over the next couple of weeks

Cheers Thumbs Up

MC

DavidW · Posted: Sun Jun 13, 2004 3:35 pm Post subject:

Just to augment my reply from last night - if you haven't yet got a GPS fix, you should try to stay stationary until you have (it's much harder for a GPS receiver to get a position fix when you're moving).

If you turn out to have a problem with the mapping that you want to report to TeleAtlas, you can do that here.

David

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