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Distance to destination

 

Is it possible to show the distance remaining to destination in place of the estimated time at destination? Would make more sense as the ETA is based on so many variables. As an aside how does the Nuvi 1300 series calculate the estimated time of arrival?

.

Have you tried pressing the ETA oval on the screen? It should give you some other options at that point.

As for the ETA Calculation, it just does the math on distance at current speed.

--
nüvi 3790T | nüvi 775T | Those who make peaceful revolution impossible, will make violent revolution inevitable ~ JFK

ETA calculation

I believe the ETA is calculated based on the highway type (e.g., rural limited-access freeway vs two-lane city street) of the remaining streets along the route. Each road is programmed with a speed rate. For example, a rural limited-access freeway may be programmed at 65-70 mph, while a two-lane city street would be programmed at 25-30 mph.

-Dave

You should

busdriver330 wrote:

Is it possible to show the distance remaining to destination in place of the estimated time at destination? Would make more sense as the ETA is based on so many variables. As an aside how does the Nuvi 1300 series calculate the estimated time of arrival?

You should be able to show distance to destination on the 1300 series by doing the following:

Tools - Map - Down Arrow (lower right corner) - Map Data Layout - More Data - OK

Now on the Map Screen you will have 3 optional display fields and the Speed. Press any of the 3 optional fields and select Distance to Destination - OK.

--
Nuvi 350, 760, 1695LM, 3790LMT, 2460LMT, 3597LMTHD and TomTom XXL540s

Question Sorted

Many thanks for your help. This is a whole new world to me! Pressed the area on the screen that was giving the ETA and it came up with a range of options, one of which was "distance to destination".

The way Garmin (and I assume other manufacturers) calculate the ETA is interesting; with variable road conditions, traffic lights etc it is difficult to understand how it can give an accurate estimate. However, will see how it works out over time.

I am not certain of this,

I am not certain of this, but I thought Garmin used as the crow flies distances. For short trips on direct routes, that distance would not be far off the summed up distances along the road taken. In larger trips, that total distance might vary significantly. Of course the time of arrival would be correcting itself along the way, & get more accurate the closer you get to your destination.

Can anyone verify if this is true?

Fred

Distance to end of trip

On the 350 if you hit the lower left box (time of arrival) it will open the dashboard window. The upper right corner will show you how far you traveled and how far you have to go.
Just remember to reset the top speed and trip after you get there or the top speed and milage will just add up on every trip you take.

--
Don't sweat the petty things and don't pet the sweaty things!

Accept and Adjust

Timantide wrote:

On the 350 if you hit the lower left box (time of arrival) it will open the dashboard window. The upper right corner will show you how far you traveled and how far you have to go.
Just remember to reset the top speed and trip after you get there or the top speed and milage will just add up on every trip you take.

I accept the number described above and adjust it slighly upward. For longer trips with the family our adjustment is roughly 10 minutes added for every hour listed on the GPS as outlined above. This accounts for food and other stops. Your mileage may vary.

--
- Missouri, Garmin 750 &, 255W

On my 765

FZbar wrote:

I am not certain of this, but I thought Garmin used as the crow flies distances.
Can anyone verify if this is true?

Fred

When I go to my Favorites and pick my daughter's house, the distance shown in the Favorites screen listing is "as the crow flies" (or 2.0 miles). When I "Go" to that destination, the "arrive in" display says 6.8 miles which is correct for that route.

That's the way

That's the way all Nuvi's work. Crow flies distance until you select a destination and once the route is calculated the distance shown is actual distance.

--
Nuvi 350, 760, 1695LM, 3790LMT, 2460LMT, 3597LMTHD and TomTom XXL540s

Yes

t923347 wrote:

That's the way all Nuvi's work. Crow flies distance until you select a destination and once the route is calculated the distance shown is actual distance.

t923347 is correct for the Nuvi 750. That is the way mine works.

--
Nuvi 750 (gave to son) Nuvi 2450

Is it using actual speed information?

OK, once the route is established, the Nuvi has the correct distance. It has already been said that it uses some default speed assumption for the type of road.

But I have the feeling that my 770 also extrapolates based on my actual speed. If for example I'm stuck at 40 mph on a freeway for some time, the ETA is adjusted like if it calculated the rest of the trip at that speed instead of 65 or 75. I can't be sure of that of course. Anybody with inside knowledge on that?

ETAs

ETAs are calculated using a complex formula with many variables, including the class of road, speed limits where known - and then it calculates an average speed over the route - and then derives an ETA based on that. The ETA constantly updates based on your driving deviations from that expected norm - newer units that are real-time traffic capable can also incorporate that data.

--
*Keith* MacBook Pro *wifi iPad(2012) w/BadElf GPS & iPhone5 + Navigon*

it depends

jgermann wrote:
FZbar wrote:

I am not certain of this, but I thought Garmin used as the crow flies distances.
Can anyone verify if this is true?

Fred

When I go to my Favorites and pick my daughter's house, the distance shown in the Favorites screen listing is "as the crow flies" (or 2.0 miles). When I "Go" to that destination, the "arrive in" display says 6.8 miles which is correct for that route.

On all NUVI units you see the crow flies mileage if you look at favorites. On some units you can press on the location before hitting GO and you can see that REAL mileage. For that reason I don't look at mileage shown in favorites or in search.

Calculation of ETA

kch50428 wrote:

ETAs are calculated using a complex formula with many variables, including the class of road, speed limits where known - and then it calculates an average speed over the route - and then derives an ETA based on that. The ETA constantly updates based on your driving deviations from that expected norm - newer units that are real-time traffic capable can also incorporate that data.

So,not unlike the gps on aircraft then which use the actual spot wind and then incorporates predicted wind (pilot entered) from some distance ahead to destination.

I find that it is amazingly accurate most of the time

busdriver330 wrote:

The way Garmin (and I assume other manufacturers) calculate the ETA is interesting; with variable road conditions, traffic lights etc it is difficult to understand how it can give an accurate estimate. However, will see how it works out over time.

I find that it is amazingly accurate most of the time and keeps updating as you travel the route so adjusts for delays, etc.

--
nüvi® 3790LMT - Samsung Galaxy Note 8.0 with Google Maps - GM Built-in Navigation system

crow

select navigation
select vehicle
any of those optional vehicles will change your distance.

Select navigation, if not in there already.
Route Preference
"Off Road" will give you "As the Crow Flies.

--
Ron Poserina. www.poserina.com

ETA Calculated from current location

jale wrote:

...
But I have the feeling that my 770 also extrapolates based on my actual speed. If for example I'm stuck at 40 mph on a freeway for some time, the ETA is adjusted like if it calculated the rest of the trip at that speed instead of 65 or 75. I can't be sure of that of course. Anybody with inside knowledge on that?

I have no inside knowledge, but just the behavior of both my old 350's and 1490T seem to indicate that the ETA on those units is calculated based on routing from the current spot, using the standard road class, and in the case of the 1490T the reported traffic ahead, if any. That is, I can be stuck doing 20 mph in heavy traffic for a while, with 200 miles to go, but the ETA is not calculated to be 10 hours later. The ETA is simply adjusted as time moves forward (but the vehicle isn't)

They learn...

Most (all?) Garmins learn your driving habits. There are several (8?) classes of roads, and it will keep track of your average deviation from the speed limits for those roads. If you consistently drive 76 in a 70 on a freeway, it will learn that, and take it into account. I've seen it claimed that the learning is based on a 2 hour moving average, so it can take a couple of hours (for each road type) to adapt to a new car/driver.

In my experience, stops aren't accounted for in the average, so the ETA is based purely on road time.

It can display both

FZbar wrote:

I am not certain of this, but I thought Garmin used as the crow flies distances...Can anyone verify if this is true? Fred

If you pull up a list such as POI or Favorites, it will show the direct line distance, but once you select one and press Go! it develops a route and then displays the route distance.

Edit: I see this was addressed by others already.

--
"There's no substitute for local knowledge"

I agree, but there is more

dconsolla wrote:

I believe the ETA is calculated based on the highway type (e.g., rural limited-access freeway vs two-lane city street) of the remaining streets along the route. Each road is programmed with a speed rate. For example, a rural limited-access freeway may be programmed at 65-70 mph, while a two-lane city street would be programmed at 25-30 mph.

-Dave

I think your evaluation is on the mark. You can see this in action if you put the unit in Simulator mode. Create a relatively short route that uses neighborhood streets, collector roads and even a stretch of Interstate. Select the option to simulate driving the route and then go to the speedometer screen and watch the speed as the nüvi navigates the route. You will see it gradually accelerate from the start, decelerate as it comes to intersections and sometimes on curves. This provides a close approximation of real world driving and the initial estimate for ETA is usually quite accurate barring real time traffic delays.

What is sometimes overlooked is that the processor is constantly recalculating the ETA from current position to destination. In simple terms, if you got stuck in a traffic jam for 10 minutes, the ETA would increment 1 second for each second you weren't moving. At the end of the 10 minutes, the ETA would have been pushed out that same amount. Variables in the remainder of the route would continue to refine the ETA to the obvious conclusion that your arrival time will exactly match the ETA in those last seconds.

What about "Adaptive Learning"? There are some who swear it exists and there are others who believe otherwise. Yes, it exists at least for the 750 which I have, but I suspect this is true for other models. and I can prove it. I had my suspicions about this early on when comparing the ETA with a friend who also had a 750 with the same firmware and maps, but the ETAs differed for identical routes. I recently completed a 3,000+ mile trip towing a heavy trailer and rarely exceeded 60mph on Interstates.

When running the above simulation that took a leg on the Interstate, it showed my speed as 58 mph. At first I thought that the trip log data somehow factored in, so I deleted the trip log and there was no change. I then performed a hard reset on the unit, and the identical stretch of Interstate now shows 70 mph instead of 58 and the ETA is noticeably sooner. This is a repeatable experiment, but it takes some time for the unit to acquire the needed pattern data. For someone who routinely pushed the speed limit, that Interstate speed in simulation might be 72 or more rather than the posted 70 for that road type.

The implication is that if a single driver uses their nüvi on a regular basis, it will adapt to his/her driving patterns. Should this driver routinely battle Dallas or Boston rush hour traffic, The ETA will likely reflect this environment and when placed side by side with one where the fellow drives open roads in Wyoming, results will be different.

--
"There's no substitute for local knowledge"

The 1690 show distance to

The 1690 show distance to turn and distance to destination as well as time of arrival.

distance traveled?

Do the nuvis have a field where they report distance traveled thus far in a route?

I know the options are for time to destination, ETA at destination, and miles to destination, but I don't find any option to show miles traveled on the route.

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nuvi 1690 with ecoRoute HD, SP2610 (retired), Edge 305, Forerunner 405

Trip odometer

speedlever wrote:

Do the nuvis have a field where they report distance traveled thus far in a route?...

The only thing that comes to mind is to reset the trip odometer on the speedometer screen at the beginning of the trip and then check your progress as desired.

--
"There's no substitute for local knowledge"

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