Crazy Route

[mvl]

So using these TomTom applications, and depending on where and If you make a stop, you will get a different route each time? The big problem is, which one is correct and when driving across country, that can be important. All routes get me to where I need to go but if I can save time & money that's a plus for me.

As the earlier post says, there appears to be an issue with very long routes. The first 6+ hours are correct then it starts doing weird stuff. I reported it in my bug thread.

Tomtom routes are time-of-day specific, so it recalculates every time your estimated arrival moves by 5 minutes. So when you stop for food or gas (sometime before 6 hours), the tomtom will recalculate your next 6 hours properly. So in reality this "long route" bug will never impact you.

Each tomtom match is catching up Map 825 p.s. has anyone else noticed that 80% of the destinations, once arriving, are off by sometimes 300+ft. This has me, as a Real Estate Appraiser, a bit annoyed but something I can get used to. Is there a fix update or is this the norm for TomTom?

Tomtom and its Teleatlas map came to North America much more recently than Garmin and its Navteq map. Since Teleatlas was new, its maps had tons of errors a couple of years ago but each map is making significant strides at closing the gap to Navteq.

I don't have house numbering issues except for a couple of streets here in Boston. There still appears to be significant issues in rural areas.

Did you plug your tomtom into your computer and install the HOME software? HOME will give you get the latest 825 map for free if you bought your 630 within the last 30 days.

 

[mvl]

I think I figured out what is going on here.

IQroutes is much slower at calculating routes, since it has to take into account so many time-of-day features.

Also, it is time-of-day specific, and will recalculate any time your estimated arrival moves by 5 minutes to compensate for differing time-of-day traffic.

I suspect that tomtom realized that there's no way a driver could go full speed without at least a 5 minute break every 6 hours or so, so they probably run IQroutes for only the first 6 hours of a trip, and then run the faster non-IQ routing for the remainder of each trip. Tomtom probably assumes that at some point in the first 6 hours, the driver will take a 5+ minute break, and the tomtom will recalculate the next 6 hours properly as the recalculation engine kicks in.

With IQ routes, tomtom usually has far better directions than any of the competition. But in the days before IQ routing, tomtom's prior routing engine was reputed to have worst-in-class directions. The old engine would assign standard speeds for each road class/size, assigning 40mph to most smaller non-interstates. This 40mph rate means the old engine would almost always keep to interstates, no matter how much longer/more congested they are.

It appears this is happenning on the tail end of long trips, so I suspect IQroutes is only running for the first 300 miles or so, and the old inferior routing is being used (for time-of-calculation purposes) for the remainder of the trip. And tomtom is relying on a 5 minute break to cause a recalc.

As further evidence of this, I tested the Quebec to New Richmod route with IQroutes disabled, and it exhibited the same 4 hour detour through Maine.

I actually like what (I assume) tomtom did. I'd rather keep the speed of calculation enhancement, since any routing calcualtions later in the trip would be inaccurate since the time-of-day actually driven would vary from the projection.