Does the Garmin expect you to drive at least 75mph on freeways?
 |
17 years
|
I had to drive my wife to the train station about 50 miles from home, in another city. She punched the station's address into the unit as I drove through our town at the posted speed limit, and it gave us an ETA of 5:04PM. By the time we got the freeway entrance, it had updated to an ETA of 5:03PM.
On the freeway, which is posted at 65mph, both lanes were going between 75 & 80 mph (middle of nowhere territory). We drove at these speeds for about 40 miles, and we were both surprised that the ETA did not update again, considering that traffic was going up to 15 mph higher than the posted limit.
In the end, we arrived right on schedule with the ETA, so the ETA of 5:03 was accurate. Yet... this indicates that the Garmin *expected* traffic to be going up to 80 mph on the freeway, and averaging 75.
Not a question, really, just an observation. Clearly the Garmin does not assume traffic will simply go the speed limit when calculating ETA's.
ETA Calculations
A little speculation here, but from what I understand about these units is that they use fuzzy logic. Since you shaved one minute off your time driving through town, it adjusted for stops (that were in town), and your driving time (you possibly got through town faster than it thought you could) and recalculated adjusting the speed upward for what it thought you would do on the highway.
Garmin Nüvi 265WT,Software Ver. 7.00, City Navigator North America NT 2010.30
i talk to a tech at garmin
i talk to a tech at garmin and he said the unit is sensitive to ur actual speed.
I watched the ETA change on
I watched the ETA change on a recent 250 mile trip. It seems to start out using the speed limits but adjusted when we went under or over the speed limit for a period of time. It takes quite a while going 5-10 MPH over the speed limit to change the ETA much if you do the calculations. This shows you how little difference it makes when you speed.
Same here
I also had noticed how often the ETA changes on my NUVI 360 when following the route that was laid out by the unit.