Show list of u-turns

[Hobbyfahrer]

Yes, that would be very helpful. Especially when importing routes this happens very often and it is hardly visible in the planning.

It would be almost even better if this is automatically corrected

[0709]

If admin thinks this should be a separate thread, please move “in block”.
It is primarily intended for the website with the aim of keeping the app simple.
Provided good experience or not, this is possible later in the app maybe.

@Hobbyfahrer

It would be almost even better if this is automatically corrected

That’s how I imagined it in the past.
Automatic was intended for the next idea.

Track snap to road and attach navigation instructions

The actual method by a simple track import has the tendency to place “waypoints” close to where the track changes direction. Such means that you often end up near the critical road junctions. Result is +/- similar as with other such applications. lnspection and repair is time-consuming, new design faster and more qualitative Therefore this alternative using “distance tickmarks”. The chance that a tickmark shaping point will fall at a critical place is less, even when using relatively high tickm…

But we’re still a long way from that, so …step by step ;-).

For the classic route planning, therefore, formulated a little less drastically.
With careful manual planning, the number of annoying U-turns is limited.
In this way, the user himself retains the desired correction control.

[rumbrummer]

From my point of view it would be better to improve route automatically - if I understand right there is an easy way to identify “wrong” U-Turns.

There was a route example supplied by @llodiers :

Route does not follow track

A friend send me a track he drove. Imported it into kurviger on my laptop and made the route follow to the track. Exported it to my mobile phone and imported it to kurviger app. Now the route isn’t the same as on my laptop and doesn’t follow my track at some places. What am i doing wrong.??? How can i make the route to follow my track perfectly [Screenshot_20210508-162707_Kurviger Pro] Original rout from kurviger.de

Loading that route (app or web) and analyzing it, all “error” U-Turns are related to wapoints:
WP7, WP14, WP15, WP16, WP27, WP37, WP38, WP39, WP40, WP43, WP45, WP48, WP49

All of them besides WP45 and WP48 can be identified by an easy rule: U-Turn conected to a waypoint, with an other turn point less than 15m before / after. WP45 and WP48 have bigger deviations due to snapping next street.

So I would provide a rule, which is executed if a GPX route or track is imported:

• If a U-Turn is connected to a waypoint, and an other turn instruction if less than 15m (to be discussed, if perhaps even 20m or 30m) before / after, shift that waypoint to the position of the turn instruction.
• after shifting all waypoints, do a new route calculation

This would fix most of the “error” U-turns in that route.

If you have further examples of routes with “error” U-turns, please provide that examples here.

Even if stopover waypoints are snapped over 30m to an other turn instruction, from my point of view this will not harm even if user has to ride in an other street for 30m.

[rumbrummer]

There is also an easy workaround on website to search for U-turns (at least in German version):

• show turn hints
• show turn hints on map:
  
• use search function of browser, search “wenden”
• click “next hit” in search function of browser
  
• click on shown hit
  

Edit: Works also in English version, search for “u-turn” instead:

[boldtrn]

@rumbrummer

• If a U-Turn is connected to a waypoint, and an other turn instruction if less than 15m (to be discussed, if perhaps even 20m or 30m) before / after, shift that waypoint to the position of the turn instruction.
• after shifting all waypoints, do a new route calculation

I am not sure if this should be done automatically. There are probably cases where this is desired to have a waypoint at such a position. For example for any parking / pause stops.

Having a system that helps to easily identify these places and maybe other potentially incorrectly set waypoints would certainly help

[0709]

Thanks Rumbrummer for thinking along.
I will read this later with more attention am just getting to my beer now. (Rain)

@0709

Planner agreement to do.
Desired scheduled U-turns should best be triggered by a Via Point.

A nice example by Wolfgang confirms the above.

Sudetenland_1_2 | Kurviger

So here no alarms nor automatic changes.

[zaphod_42]

Hey - thanks a lot for this “trick” to search “wenden” in turn hints! Up to now I scanned the .kurviger file with Notepad++ for “-98”.

Btw: My current workflow for taking tracks from outside is simply to “convert” them with GpxShaping to a route. The waypoints (intelligently set by GpxShaping) are then taken from kurviger import.

If you like a test: shorttrack.gpx (77.7 KB)
Directly imported in kurviger → 4 times “wenden”
Taking GpxShaping in account → no “wenden” at all

[devemux86]

@zaphod_42

Up to now I scanned the .kurviger file with Notepad++ for “-98”.

You should search for all u-turn types (see here):

• U-turn unknown: -98
• U-turn left: -8
• U-turn right: 8

[0709]

@ rumbrummer

A. The tip with search u-turn or “wenden” you thought up well. Makes locating easier.
In a tool version, of course, the presentation should be completely language independent.

B. Route planner design.
I do not think of automatic corrections actually. I prefer to keep control of this myself

C. The tip for automatic correction I doubt, since I prefer a ROBUST @ simple rule

The Rumbrummer proposal I had imagined as follows.

1. Assign misplaced Shaping Point the coordinates of the enclosing turns then MAGIC ! Only the unannounced Shaping Point remains.

2. But Shaping Point & U-turn(-98) are not necessarily enclosed between between 2 consecutive turns at exactly the same location.

    A. False turn > Shaping U-turn > Correction turn. U-turn CLEARLY enclosed. Robust.
    B. (Continue) > Shaping U-turn > Correction turn. U-turn not enclosed. Robust? 
    C. False turn > Shaping U-turn> (Continue). U-turn not enclosed. Robust? 
   

D. Left or Right U-turns because of this are extremely rare. I’m not worried about that.

The essential not to forget.
Design accurately then hardly any such corrections are needed

[0709]

@0709

Assign misplaced Shaping Point the coordinates of the enclosing turns then MAGIC ! Only the unannounced Shaping Point remains.

I tested the method a little more. Unfortunately not always 100% successful. I took the turn coordinates (6 digits after the comma), but sometimes still a track glitch appeared. It is too delicate for me. So I still do prefer manual correction. Fully automatic without final check I do not trust. You can just as quickly move a few wrongly positioned shaping points a bit further away from the critical road crossings.

[devemux86]

@0709

So I still do prefer manual correction.

This seems the best solution.

[0709]

Avoid undesirable U-turns by optimal map display.
Advise: “Unset Turn instruction nodes”.

1. Plant desired U-turn by announced Via Point & Icon.
2. Good Shaping Point. White Circle Icon. (Shaping-Continue combi).
3. Bad Shaping Point. Red Circle Icon. (Shaping-U-turn combi).

See Circle Red ? Move until White.

(Website & app)

[devemux86]

U-turns can also exist on via points.

[0709]

True.
I suppose by a Via edit U-turns so are mostly intentionally planned so I did nog suggest a “red” light warning signal.
Anyway Emux if you have a different opinion you are completely free to (eventually) apply this also on Via’s. No objection, of course not.

By the way the import file in the .gif was next one.
TET_trk_0.50km_rte_ticks.gpx (13.9 KB)
Import (gpx) route
Overlay: Track
Routing: Route
Unchanged
Max waypoints: 200

[0709]

Information.
Locus recently has introduced also a trackglitch alert into the Locus Planner using the offline BRouter engine.
After tests I found out there is a small difference in track generation production by both router engines GH or BRouter.
Locus so optimised this alert method mainly for the prefered Locus_BRouter offline planner.
Read more in next.

https://forum.locusmap.eu/index.php?topic=7575.msg65369#msg65369

[rumbrummer]

I did a try in a beta version of my converter(gpxshaping.de Beta Versions) and implemented search buttons for previous / next U-Turns.

If marker is placed on a U-Turn waypoint, you can shift that waypoint to prevent U-Turn.

Via this test link U-Turns, you can have a look and try easiely with the route supplied by @llodiers in

Route does not follow track

A friend send me a track he drove. Imported it into kurviger on my laptop and made the route follow to the track. Exported it to my mobile phone and imported it to kurviger app. Now the route isn’t the same as on my laptop and doesn’t follow my track at some places. What am i doing wrong.??? How can i make the route to follow my track perfectly [Screenshot_20210508-162707_Kurviger Pro] Original rout from kurviger.de

As far as I can see this algorithm works fine - perhaps it would be useful to do the shift automatically in Kurviger (app and website), if a track has been imported and a route fitted onto it (as far as I understand, the example of @llodiers was created by importing a recorded track into Kurviger).

If you have further testcases or any ideas for improvement, please give feedback.

[zaphod_42]

Just great Markus,
to find the u-turns is already easy, following your tipp to look after “u-turn” at the turn instructions. But your approach is even better! And perfect is the shift of the appropriate waypoints.
Thanks a lot for your idea and the realisation!
Wolfgang

PS:

@rumbrummer

perhaps it would be useful to do the shift automatically in Kurviger (app and website)

Sure this would be great as well - but how should the algorithm differentiate between “false” and “true” u-turns, which are also possible?

[rumbrummer]

Hi Wolfgang,

@zaphod_42

Sure this would be great as well - but how should the algorithm differentiate between “false” and “true” u-turns, which are also possible?

I think after importing a track for routing the probability of “false” (= unintended) U-Turns is very high - therefore my additional remark:

@rumbrummer

perhaps it would be useful to do the shift automatically in Kurviger (app and website), if a track has been imported and a route fitted onto it

But that is just an idea based on theoretical consideration - my experience with importing tracks as base for routing is quite low!

Regards
Markus

[boldtrn]

Thanks for providing this nice idea @rumbrummer. I do have something like this on my list as well.

@rumbrummer

perhaps it would be useful to do the shift automatically in Kurviger (app and website)

Automatically is probably not that great. Manually with some button or some sort of UI, I would agree that it would be a nice addition .