Route Change

jcjeffe · Occasional Visitor Joined: Mar 12, 2007 Posts: 17

Having plotted a route to a destination has anyone had TT6 plot a totaly different route the next day?

I was traveling from my mothers house to my brothers house the other side of Huddersfield about 30 minutes drive away. The easy way is to go almost through the town centre but my brother takes a back route which should save a mile or two looking at a map.

TomTom plotted a route which I thought followed my brothers route but actually took a cross country route where the roads were not that wide. I was not keen on this route so the next day replotted the route but forced it to take my brothers route. Although this route was 1.5 miles shorter it took a minute longer than the original route.

Since then when I give it the same start and finish points the route follows the roads of the shorter route which I previously had to force it to take. I have tried re plotting using the two postcodes in Avanced Planning and with the GPS on using the destination postcode and it still takes the shorter route which it has now decided takes the same time as that original route.

Chris

Flack · Posted: Fri Oct 12, 2007 10:46 pm Post subject:

When I want to use my own route I use Itconvert with Autoroute, you just plot the route you want in Autoroute and then convert it with Itconvert so you can get TT to use it as an itinerary.

Flack Very Happy

Trevor1234 · Posted: Mon Oct 15, 2007 1:34 pm Post subject:

Hi jcjeffe
As Flack has alls ready suggested you can plot a route on your PC with Autoroute and its converter, ITNconvert.

Even better is Google Maps. You can plan your route on Google maps and then log on to a site at http://houghi.org/tomtom/index.php and follow the instructions. Its great.

You can also plan a route using the Itinerary option on Tomtom.

Any of the above three option will make your Tomtom take you on the route that you wish it to take. I know, I have tried them all.
_________________
Tomtom Go 720.
Navcore 9.510
Central and Western Europe v855.2884
GPS World Traffic cameras
Home 2.7
iPhone 3G

TTOV3 · Occasional Visitor Joined: Oct 09, 2007 Posts: 20

jcjeffe · Occasional Visitor Joined: Mar 12, 2007 Posts: 17

Everyone seems to have got the wrong idea. All I was asking was has anyone seen TomTom plot a route one day and the next day plot a considerably different route between the same two locations.

Between times I had forced a test route which to me seemed better but which TomTom said took longer than its initial route, but only by a minute. Ever since then TomTom has started using this route instead of its original one.

Chris

Trevor1234 · Posted: Thu Oct 25, 2007 12:43 pm Post subject:

Hi jcjeffe
I'm sorry, we did wander off from the original query. And I am also sorry that I haven't got the answer to your question.
_________________
Tomtom Go 720.
Navcore 9.510
Central and Western Europe v855.2884
GPS World Traffic cameras
Home 2.7
iPhone 3G

AllyCat · Posted: Fri Oct 26, 2007 12:12 am Post subject:

Hi Chris,

TomTom does seem to plan its route for the direction it thinks the car is currently facing (i.e. the last direction in which the gps was moving). If the two routes take a similar time (or whatever criteria you've set), or you're starting on a long road with no turning points, could that be the reason?

Cheers, Alan.
_________________
Garmin GPS72H/76/60/45, Etrex H, Mapsource v6.5.
Acer N50,HP114,Loox N560,Dell x50,CF/SD cards to 4/32GB.
RoyalTek,Holux236,Navman B10 & Copilot(Globalsat) BT GPS,TomTom5/6.
Memory Map (v5.4.2 & v5.1.3 OS & Euro), GPS gate,OSGPSconverter.

spile · Regular Visitor Joined: May 08, 2004 Posts: 163

Yes, I am suspicious that TomTom seems to "learn" routes. It would be nice to have a definitive answer but I suspect that only the bods at TomTom HQ would know the answer to this.

Robin2 · Posted: Tue Oct 30, 2007 9:25 pm Post subject:

I am sure that TomTom does not learn routes.
However, other factors might be different, accounting for the different answers. As previously suggested, one of these might be the direction the car was moving when the GPS was previously switched off. Also, if two alternative routes are very similar in their scores, minor differences in the perceived GPS start position (for example, placing the car on different sides of the road) would favour one or the other. Finally, the calculation of the route is not performed to an infinite degree of precision. There are rounding errors at each stage, and these might result in different routes appearing to be fastest at different times.
Robin[/u]
_________________
TomTom One v3 Europe, Navcore 7.903, Western Europe 835.2420
TomTom Go 720 Europe, Navcore 8.351, Western Europe 855.2884
Satmap Active 10
Plus a lot of other PDA GPS kit, seldom used

Calomax · Posted: Wed Oct 31, 2007 9:56 am Post subject:

Robin2 said

philpugh · Posted: Wed Oct 31, 2007 6:34 pm Post subject:

Yes - and you can 'confuse' it by reversing into a parking position on the road. It correctly thinks it's moving the 'wrong' way.

I don't think it will pick which side of the road you are on - it works this out from the position of the centre of the road (the lock-to position) and the direction of travel and country.
_________________
Phil

	PocketGPS
	Web