Author Topic: entering turns manually vs. map navigation (EDGE 820, may have wider relevance)  (Read 1613 times)

StevieB

  • I'm an embarrassment to my bicycle!
So I jumped from the 500 to the 820 and was thrilled to find the unit's navigation was automatically telling me to turn right, left, etc. No more entering instructions manually!

Soon I got dismayed... while the unit made a song and dance at every corner in the road, at some T-junctions and cross-roads it was struck dumb...

Back to entering the instructions...

Then on longer rides the unit started to crash, seemingly on a turn where there was an overlap of instructions. (Generally I'm convinced the unit keeps on recording, it is just the display which freezes.)

Anyway, for LEL, I've decided to not enter any turns manually and follow the route sheet closely. That is not ideal, particularly at night. (No dynamo, so won't have the screen on all the time.)

Thought to look at the list of instructions the navigation generates (to fill in the missing ones), but this isn't shown until the start of the route.

Thought to use Garmen Connect, but get errors loading .gpx and .trx files.

Am I using the 'wrong' map? Should I turn off the navigation?
It may be self-flagellation, but it still hurts

at some T-junctions and cross-roads it was struck dumb
That's because the map doesn't contain good information on where the white lines at a junction are, so it works on road direction.
You'll also get it telling you to turn left where there's a fork off to the right, when the road markings just have you continuing on the same road.

StevieB

  • I'm an embarrassment to my bicycle!
Thanks Andrew,

Whatever the reason (and it does get things right 90% of the time), it is still frustrating to miss a turn.

That is really what I'm worried about - not the T-junction or the crossroads, but sailing past a simple left or right.

If I understand you correctly, that will not happen, unless the turn is effectively a SO and the road markings are not clear...?

Not a solution, but it narrows down the problem and I know what to look out for!
It may be self-flagellation, but it still hurts

Kim

  • Timelord
    • Fediverse
at some T-junctions and cross-roads it was struck dumb
That's because the map doesn't contain good information on where the white lines at a junction are, so it works on road direction.

I think it's more a case of the map, by its very nature, having a model of which road is major and which is minor (this being important for things like drawing road names and making routing decisions), but this data is derived from sources less reliable than someone going out and eyeballing the junction markings.  If there even are any.

Any satnav will have this problem at some point.

In practice, I find that it rarely happens with turns onto a side road.  And if you do overshoot, you'll cause the route to re-calculate and get beeped at in short order.  More common is to arrive at an ambiguous junction and find it hasn't beeped an instruction at you because it thinks you're staying on the same road, or for it to give superfluous turn instructions when a physical turn is a logical straight on.