Etrex Legend HCX routing advice

[_bigfoot_]

hi

I purchased an Etrex Legend HCX a few months ago - mainly due to the cost and excellent battery life (not reliant on a charger). Compared to my Forerunner 310XT I was initially disappointed with the poor routing using tracks and inability to use bikeroutetoaster.

Thanks to the great info on this site, particularly frankie frank, I'm switched to created routes using Mapsource and have been impressed with the "do follow" routing.  I am using the talkytoaster openstreetview UK maps on both the Etrex and mapsource.   I have some questions.

1) If I plot a route in Mapsource, it doesn't seem the etrex will always interpret the route in the same way.   

My etrex is setup as :  Prompted, Shorter Distance, Best Route, Delivery (avoid toll roads, unpaved roads, carpool lanes)

mapsource is setup as : delivery, shorter distance, road selection slider is in the middle, auto routing (avoid toll roads, unpaved roads, carpool lanes, date and time closures).


During my ride through the Chilterns yesterday, I noticed the Etrex tried to get me to cut corners by taking me down trails (which appear as dotted lines in openstreetview).

How can I stop this?   The mapsource route does not do this.    I appreciate I can me more particular with my routepoints but I'd rather not have this overhead.



2) Whilst on my route yesterday, the road forked and then joined up to the same route later on.   The etrex appeared to highlight both roads on the fork - as if giving me a choice.   This was not so on the mapsource route I'd plotted.  Is this a feature or was something messed up?


3) Is there any way to make the track line more visible?   The route line is nice and clear but the track line just looks like a normal road to me.


thanks

[Manotea]

The problem is that the PC and GPS seem to use different algorithms to calculate routes. For this reason many AUKS eschew using routes and just rely on tracks.

See here for my approach to using routes and tracks.

If you config bout route and track, use contrasting colours. For example, white for the route, Dark blue for the track or vice vesra.  THat way you can distinguish between the two and it is immediately clear if the route is going off-piste.

[frankly frankie]

How can I stop this?   The mapsource route does not do this.    I appreciate I can me more particular with my routepoints but I'd rather not have this overhead.

I think that is the only sure way.  It's not as though you need loads more points - how widely spaced are they at present, on average?  I'd suggest if they were 5km apart, on average, you'd be unlikely to go wrong in a rural environment.  Some people seem to expect it to work when points are >20km apart - I think this is a bit optimistic.

[edit] plus, I have slowly realised that 'Delivery' (which works really well in towns) isn't the best choice for cyclists on rural roads - by definition, it's going to take you round the houses whenever possible.  I don't know what the best setting is (I don't think there is any one best setting) but I now use 'Car' on the rare occasions when I use autorouting at all, outside of big towns.

2) Whilst on my route yesterday, the road forked and then joined up to the same route later on.   The etrex appeared to highlight both roads on the fork - as if giving me a choice.   This was not so on the mapsource route I'd plotted.  Is this a feature or was something messed up?

That would have to be a autorouted U-turn on one of the legs, I can't see how else it would happen.  Possibly caused by a 1-way instruction embedded in the OSM map, or a malformed junction.  Maybe the 'delivery' thing.

I do think, personally, that autorouting using OSM is pushing the envelope a little.

3) Is there any way to make the track line more visible?   The route line is nice and clear but the track line just looks like a normal road to me.

Colour the Track, either do it in Mapsource (Properties) or in the GPS Track menu.  I choose bright green because that isn't used at all by the Garmin maps.

[_bigfoot_]

thanks for the feedback.   I'm hoping to do JOGLE either this year or next, so want to iron out all the niggles/anomalies with the gps.   Tracks are not an option on the Etrex because a)no arrow directions and b) the track line is just not visible enough regardless of colour (it would be ok on aero bars but not with my road bike position).

It's a shame Mapsource doesn't have an option to select GPS unit and match the algorithm accordingly.   Would eliminate any suprises out on the route  

how widely spaced are they at present, on average

My route was 90K and the points were spreadout less than 5K apart.  It worked well apart from on a couple of corners where an off road trail cut the corner and the GPS wanted me to go down it.

If you config bout route and track, use contrasting colours. For example, white for the route, Dark blue for the track or vice vesra.  THat way you can distinguish between the two and it is immediately clear if the route is going off-piste.

I will give the white track idea a go.

I do think, personally, that autorouting using OSM is pushing the envelope a little.

What are my alternatives?   As above tracks are out.   I like the way the autorouting pops up nice arrows on junctions and roundabouts and gives me plenty of warning.   The arrows are very clear and readable, unlike any of the screen text.


edit: on the etrex: what is the difference between best route and better route?  Also rather then delivey - what is using bicycle like?

edit2: below is image of my route (post ride from Etrex), it tried to take me down the dotted line which was through a field.



perhaps I need to create a custom map with no trails (suprised Etrex can't avoid them)    In all seriousness, another route marker would have prevented this, or I guess I could have set Etrex to use quickest route rather than Shortest, but this is likely to try and stear me onto more main roads if route points are too far spaced......

No matter what option I use in mapsource - I can't get it to steer me down these trails....grrrrr

thanks

[frankly frankie]

edit: on the etrex: what is the difference between best route and better route?  Also rather then delivey - what is using bicycle like?

best   just takes longer to calculate.  I think the options are really a throwback to older models with less processing power than the HCx.  It's not really a problem unless you have it recalculating frequently as you go along (very very bad idea).

... or I guess I could have set Etrex to use quickest route rather than Shortest, but this is likely to try and stear me onto more main roads if route points are too far spaced......

As a cyclist, I would definitely always want to know about the 'shortest' option first!!

[PloddinPedro]

edit2: below is image of my route (post ride from Etrex), it tried to take me down the dotted line which was through a field.



....
No matter what option I use in mapsource - I can't get it to steer me down these trails....grrrrr

I haven't tried the maps you are using, only the City Navigator that came with my Garmin, but my experience is that oddities such as that in your illustration are caused by flaws in the base data in the mapping database. Roads can sometimes get input erroneously as Bridleways and vice versa. Consequently the Routing algorithms see the lines as "roads" and logically use them.

This is also one reason why "Bicycle" isn't always the best setting - the bike the Garmin people have in mind seems to be a cross between an MTB and something with a wicker basket on the front; i.e. it can go anywhere, bridleways included!

Flaws in the mapping database can also explain the oddity of appearing to run up against a fork in your route which appears to offer a choice of directions. In fact what's happening is that the Route goes ahead until it meets a perceived break in the road, caused by a flaw in the mapping; it then reverses and returns on itself until the junction where you have the apparent fork, takes the other turn and finds an alternative way around the imaginary obstacle; it then rejoins the correct road further ahead, backtracks towards you until the next waypoint and then reverses and retraces to continue again on the original route! Very clever, but stupid. Your problem of course, is that at first sight, you don't know which way is the proper route and which way is the loop; to determine this, you have to zoom out steadily until you can see the whole picture on screen, in the shape of the Route, when it should be visible which is the false direction.

[_bigfoot_]

cheers Pedro.