why did garmin start taking me back home

[rufasim]

I was out for a ride the other day and wound up getting off the wrong exit. It told me I needed to get off exit 46a, but the exits were re numbered so I wound up getting of 46b. I figured my mistake so I made a u turn once I got on the road. Garmin wasn't as fast as I was to figure this out and had me getting back on the high way and heading home. The only way I knew I was heading home was because it stated that I would be home about an hour and a half earlier than what was stated before my mistake. I got off the high way again and started heading in the right direction and Garmin found its way and brought me to the final destination.
Why would the Zumo bring me all the way home rather than set me in the right direction? This has happened to me using the oem gps on my Goldwing before also. I was just about to re start the route to see if that we set me right but just getting off the high way and heading in the correct direction did that for me

[jfheath]

I know exactly how this may happen. See if this description fits your circumstances.

If you join a magenta line heading in the wrong direction, there are circumsatnces when the Zumo will continue navigating in the homeward direction without taking you to the place that you intended to go. You have joined the route heading in the wrong direction. Only an idiot would do that by mistake and it assumes that you are not an idiot, so you must have done it deliberately. So it takes you where it thinks you want to go. Home.

Zumo 660 users will be familiar with this behaviour. Make a circular route starting and ending at home on the 660. Turn on the stanav and just as you start moving it tells you that you have reached your destination.

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A simple route consists of a start and a finish point. In between is a magenta line that is plotted by the XT (and any Zumo) - which the XT will follow and give you instructions.

Then it has a couple of different types of point that will pin the route in place. Garmin calls these points Via Points and Shaping Points.

Via Points appear on the Zumo map as orange flags. These are used for serious stopping places. You are definitley going to visit these and the XT's job is to take you to them. The XT sometimes calls them 'Destinations'. Coffee breaks and such like. Maybe 4 or 5 in a single route. They announce as you approach and when you arrive.

Shaping points are not as serious. These appear on the XT map as small blue discs. No announcement as you approach or arrive. Their job is to make sure that if the Zumo recalculates a route it will plot a new magenta line through each of the remaining shaping points (and via points) in the correct order. But the Zumo does not insist that you visit a shaping point as long as you are somehwere on the route.

Lets take a couple of examples. You want to go out for the day just to visit somewhere nice. You decide to take the same route there and back - except coming back you are on the other side of the road and heading in the other direction.

You have a start, a finish and a route point at the "somewhere nice" place. There is one magenta line form start to finish which then doubles back and continues in the other direction on the other side of the road to take you home. You may see this if it is a dual carriageway. If it is a two-way road, you may just see one magenta line unless you zoom in on the map.

You take the wrong exit, and in order to correct the mistake you happen to join up with the magenta line heading back home. That's all it needs - it assumes you are now wanting to get home.

Now how this happens on the XT is explained by the use of via points and shaping points. If your route uses only shaping points, it will behave like the 660. Yes it will navigate you to each shaping point in the correct order and it will recalculate the route to go and visit the next one on its list. But if you happen to join up with the magenta route having missed any number of shaping points, then it doesn't care. You are on the magenta route, you must have intended to miss them out, so it continues navigating from there.

But if you put a Via Point in the route, that doesn't happen. It won't let you miss out a via point, even if you join the magenta route after the via point. It will take you back.

And here's a possible reason. Many route planning apps do not have the facility to put in Via Points and Shaping points - with the charactersitics that Garmin uses, and which I have described. Instead, they refer to everything as Waypoints. And that is even more confusing, because a Waypoint is something completely different as far as Garmin is concerned. It is a 'Favourite' or a 'Saved Location'. When one of these is put into a route, what matters is whether it was set as a Shaping Point or a Via Point.

Some routing software inserts only Via Points. Some routing software inserts only shaping points. Very few use bothe types of point in the same way that Garmin does. And the XT is a Garmin device.

The only two that I know of that make this distinction are Basecamp and MyRouteApp. For myRouteApp, this is a very recent addition, and you have to be careful which gpx format you uses.

Some questions:

What mapping software did you use.
Did you have any orange flags on your Zumo route map (Vias Points)
Did you have any blue discs on your route map (Shaping Points)

Is it possible that you picked up the magenta route that was heading back home when you took the wrong exit ?

If you think this is a possibility, make sure that you have at least one Via Point in mid route. That way, it cannot possibly allow you to pick up the route home and think that that was your intention. It HAS to take you to the Via Point before it can jump into the middle of the section After the Via Point.

ps - I used the phrase 'only an idiot'. I don't mean any offence by that, if that is what happened to you. Far from it. There's a reason that I know of this particular situation. Only an idiot would have found out that it did that. Yeah. That'd be me too then !

[rufasim]

I planned the route on google maps and transferred it into basecamp. I then down loaded the route in the the garmin from BC.
I just looked at the map on the zumo and there are green flags. The flags appear to be where I put waypoints when in basecamp. There are green flags on the map that are not on any part of the route, just a different part of the state all together. Looks like waypoints I installed on another route. They are not part of the magenta line so they did not effect the route at all. Does all this make sense?
I did go back over a magenta line in the opposite direction so that makes sense why it was taking me home.

[jfheath]

The green flags - are they green squares with a white symbol in them ?

If so, these are the 'up ahead places' - in this case the Favourites / Saved Places / Waypoints that are saved on your XT. You can access the list by selecting 'Where To -> Favourites'

I'm not a fan of using Google maps with the XT. I did look into it years ago, and compared the maps and the gpx files that were produced. It would be wrong to repeat the conclusions from years back. Things have changed so much since then.

If you want to attach the gpx file that you navigated I'll be able to tell you precisely what went wrong and what you can do in future to make it right.

I think my original post will be pretty close - but we shall see.

[rufasim]

No, the flags were solid green. I do believe they were waypoints that the zumo saved for future routes because I deleted them. Easy enough to put back on if needed. I saved the route. The GPX file has only a start and finish points, about 1/4 mile apart form each other. It was a circular route. Only those 2 points were verbalized during the ride. The rest we rode past and never heard where we were. The interesting thing was that it verbalized the name of the route, not the location we were at.

[rufasim]

From what I think I might have figured out is the green flags are shaping points that appear on the zumo xt map. They are shaping, not via points because there is no announcement when I arrive at them. This is fine with me as long as I know I am going in the right direction. These shaping points are put on in basecamp after I upload the route from google maps. They are being shown as flags, not dots for a reason I do not know. If this is correct, I am fine with this. I usually don't stray to far from my planned route other than trying to find food or gas. It would be interesting if I could change a shaping point to a via point on the rare occasion that I do want to see something that is not near my route. That is my next project to look at. Am I on the right track in my thinking?

[jfheath]

Ok - I think you must be seeing the 'Explore' icons for the points that were created as Waypoints in Basecamp. They get transferred to the XT when you send your route. If you send the route to Internal Storage from Basecamp, they get placed into Favourites on transfer. If you send the route to the SD card, you have to import the favourites before you can see them.

So yes, you are pretty close to understanding what is going on.

Waypoints will appear in the route as either Shaping Points or Via Points. If you changed them to non alerting, they will be shaping points.
You can also send Waypoints that are not part of a route. They show up as icons on the map too.

If you zoom in closely on the XT map, you will probably see the blue disc underneath the little flag. Both are shown on the XT map.

I'm working on something for you, but I need to get some decent sized images displayed. I may need to add it to the 'Zumo XT - Everything You Need to Know' article. I'll let you know when it is done.

Do you have a free account at explore.garmin.com ? You don't need one. I'm just asking as it changes the way I write my reply !!

[jfheath]

Questions Answered Part 1 - Basecamp Route.

One route on a Basecamp screen. Including the start and the finish there are : 5 route points. 4 Waypoints. 3 Via Points, 2 Shaping Points.
Note the clues - the blue circled point and the highlighted red box and the Route Properties.

Can you work out which is which ?? What is the issue with P4 ??

[jfheath]

Question Answered Part 2 - Waypoints shown on the XT screen.

These two screens show the same thing - the zoomed out map with just the Favourites showing. At this point, the route has not been loaded, but they Waypoints are stored in Favourites automatically if the route is transferred to Internal Storage. You do not need to import favourites unless you transfer routes to the SD card, or they have been transferred without being part of a route. Waypoints mark places on a map that are not necessarily part of a route.

This map shows the Garmin Explore stye waypoints. They default to small green flags. I have selected different colours for each of them.
I emptied the Zumo of other favourites before getting this screen shot. These are only the waypoints that were sent with the route.

P102b XT Explore Waypoints.png (751.07 KiB) Viewed 1262 times

This shows the same thing, except the Garmin Explore link has been disabled. Instead, much larger icons can be turned on in 'Up Ahead Places', Favourites default to showing up as hearts, but the icon can be changed. Not very pretty. I dont turn this feature on as in this case it also turns on 3 other categories - hence the restaurant icon..

P102c XT Favourites.png (956.54 KiB) Viewed 1262 times

[jfheath]

Questions Answered Part 3 - XT Route Map and Symbols.

Here is the full route showing the magenta line, the waypoint flags and the Via and the route point symbols. There are 5 route points, starting with P1 at the bottom where the bike is shown, and P5 at the top where the chequered flag is.

Large Orange flag is the start of the route (P1)
Large Chequered flag is the end (P5)
Large Orange flags are the announcing Via Points. (P3)
Small blue discs are the non-announcing Shaping Points. (P2 and P4)
The user has no control over how these appear on the map.
The waypoint symbols are suprimposed on these - so route points that were first created as Waypoints will be marked with two symbols)

Note in particular the P4 shaping point shown as a small blue disc - the one that was created with the insert tool.
Also the blue disc at P2 - which has a small yellow flag. This was created as a Waypoint, but made to not announce - so it is a shaping point with a flag.
P3 has the orange flag to indicate a Via Point, and also a green flag in this example indicating a Saved location - ie a Waypoint.

Waypoints / Saved Locations / Favourites (they are all the same thing) can have different symbols assigned and, as in this case, there are options to choose the same symbol in different colours. Groups of Waypoints can be made and placed in one or more collections. Collections can be turned on and off, so that you have full control over which ones are displayed on the map.

It is not possible to change the orange flag and blue disc icons that are used to represent Via Points and Shaping Point on the route.

Much more about this can be found in Zumo XT and Basecamp - Everything you need to know

The link to the pages relating to the above is here: app.php/ZXT-P66