# Navigation stops after several rerouting attempts

**URL:** <https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952>\
**Category:** App\
**Created:** [February 22, 2021, 9:06am UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952 "2021-02-22T09:06:20Z")\
**Posts on this page:** 19\
**Page:** 2

<div class="post-metadata">

**Author:** ![0709](https://forum.kurviger.com/user_avatar/forum.kurviger.com/0709/32/4699_2.png) [@0709](https://forum.kurviger.com/u/0709)\
**Post date:** [February 24, 2021, 8:50am UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/23 "2021-02-24T08:50:53Z")

</div>

Example with the Kurviger online router. See video.

[![]( " - YouTube") ](https://www.youtube.com/watch?v=tHeDpT12Gw8)

Demo.

_When you arrive at the junction with the L1103, follow the diversion to the L1110._  
_The false moving direction is shown by the increasing turn distance indicator._  
_So you now get 3 consecutive 180 ° turns that you refuse._  
_Immediately after the third 180° turn in a single row add an obstruction._  
_(Now a job to do manually - automatic trigger possible?)_  
_This causes a new recalculation and a fwd drive proposal further toward the L1110._  
_The rider later changes his mind and still want to enter the L1103 anyway._  
_So turn on the next roundabout and have a return._  
_You now again get 3 consecutive 180 ° turns that you refuse._  
_Immediately after the third 180° turn in a single row add an obstruction._  
_(Now a job to do manually - automatic trigger possible?)_  
_You will then receive the renewed proposal toward the L1103._

_NOT implemented in the Kurviger app !_  
_- Detect a false opposite travel direction by the steadily increasing distance indicator to next turn._  
_- As long the travel direction is the opposite of the calculated route direction, add the msg 'Try to return"._  
_- If the user keeps ignoring the “Try to return” request the app should block the return path by add obstruction._

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<div class="post-metadata">

**Author:** ![devemux86](https://forum.kurviger.com/user_avatar/forum.kurviger.com/devemux86/32/6239_2.png) [@devemux86](https://forum.kurviger.com/u/devemux86)\
**Post date:** [February 24, 2021, 4:30pm UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/24 "2021-02-24T16:30:17Z")

</div>

Automatic rerouting is overrated and can produce strange results in all navigators.

Exit / enter route anywhere and [manual rerouting](https://docs.kurviger.de/app/faq/navigate_with_manual_rerouting) remain the optimal way to drive.

> [@0709](#):
>
> If GH is available offline again, I will be happy to remove BRouter.

GraphHopper cannot work with [Android SAF](https://developer.android.com/training/data-storage#scoped-storage). Its focus is more on [online routing](https://github.com/graphhopper/graphhopper/issues/1940).

_BRouter profiles and customization are unmatched by all known routing engines._  
(and is the only _offline_ routing service available at this time)

---

<div class="post-metadata">

**Author:** ![0709](https://forum.kurviger.com/user_avatar/forum.kurviger.com/0709/32/4699_2.png) [@0709](https://forum.kurviger.com/u/0709)\
**Post date:** [February 24, 2021, 6:26pm UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/26 "2021-02-24T18:26:58Z")

</div>

@ RHoffner  
When an identical case happens you again, you could try to halt multiple annoying recalculate messages as indicated in the demo video by a manual action. The price to pay is you should halt your bike for safety reason, put out the gloves, tap the screen to add the obstruction, before a ready to go again. What I want to show is that after 2 ignored 180° turns at the 3 e recalculate attempt the app would already understand and add an obstruction automatically. Anyway other ideas welcome.

> [@devemux86](#):
>
> Automatic rerouting is overrated and can produce strange results in all navigators.

The barrier of the L1103 to Pfaffenhofen.  
In order of preference.

1. The most optimal: The barrier in Pfaffenhofen is indicated in osm. (Is not)
2. Manually indicate the blocking while you are still on the route, this where the detour starts at the L1110/L1103. (Didn’t happen).
3. Follow the detour and either manually or automatically as suggested you place a block on the returning L1110 route back toward the missed L1103.  
You will get an alternative but you have to be very attentive because it may well be that an alternative will just bring you back to the still unblocked L1103.  
Placing an automatic blocking on the L1110 where you do not want to roll back do prevent the multiple almost identical recaclulate commands .

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<div class="post-metadata">

**Author:** ![devemux86](https://forum.kurviger.com/user_avatar/forum.kurviger.com/devemux86/32/6239_2.png) [@devemux86](https://forum.kurviger.com/u/devemux86)\
**Post date:** [February 25, 2021, 7:21am UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/27 "2021-02-25T07:21:33Z")

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BRouter supports nogo areas.

GraphHopper plans to deprecate the block\_area:  
(also used in [“Avoid roadblock” feature](https://forum.kurviger.com/t/app-avoid-roadblock/186))

> **[Polygon blocked area issue](https://discuss.graphhopper.com/t/polygon-blocked-area-issue/6336/4)**
>
> It should be fixed in 1.0: https://github.com/graphhopper/graphhopper/pull/1917 If you still encounter problems please write a simple reproducer here and make sure you use the correct format (see the api docs) Additionally I would recommend to...

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<div class="post-metadata">

**Author:** ![RHoffner](https://forum.kurviger.com/letter_avatar_proxy/v4/letter/r/3da27b/32.png) [@RHoffner](https://forum.kurviger.com/u/RHoffner)\
**Post date:** [February 26, 2021, 7:22am UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/28 "2021-02-26T07:22:33Z")

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Hi 0709,  
It is not always possible to find a spot where you can safely park your bike. Currently i add an electroconductive thread to my gloves to do this operation quickly.  
Thanks for the support.

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<div class="post-metadata">

**Author:** ![0709](https://forum.kurviger.com/user_avatar/forum.kurviger.com/0709/32/4699_2.png) [@0709](https://forum.kurviger.com/u/0709)\
**Post date:** [February 26, 2021, 5:44pm UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/29 "2021-02-26T17:44:49Z")

</div>

I tested a local real deviation circuit. Kurviger online had 12 x recalculate msg’s before a usefull new route was calculated and offline BRouter had 11 x recalculate msg’s (Fast to route: set)  
.  
It would be nice if Kurviger automatically accepted the “boss” road preference a little faster.

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<div class="post-metadata">

**Author:** ![linux-user](https://forum.kurviger.com/user_avatar/forum.kurviger.com/linux-user/32/56_2.png) [@linux-user](https://forum.kurviger.com/u/linux-user)\
**Post date:** [February 27, 2021, 7:04am UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/30 "2021-02-27T07:04:39Z")

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> [@0709](#):
>
> I tested a local real deviation circuit …  
> It would be nice if Kurviger automatically accepted the “boss” road preference a little faster.

Could you post both routes so we can reproduce the example:

- the url of your original route example
- the the url of the preferred detour (=“boss” route)

> [@0709](#):
>
> …  
> Kurviger online had 12 x recalculate msg’s before a usefull new route was calculated.  
> Offline BRouter had 11 x recalculate msg’s before a usefull new route was calculated.

What setting have you in `Settings | Navigation | recalculation mode`?

Apart from that, I think it is very difficult to create an algorithm that does 2 contradictory things at the same time:

1. keep the original route as good as possible
2. switch to an alternative route (=detour) as quick as possible

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<div class="post-metadata">

**Author:** ![0709](https://forum.kurviger.com/user_avatar/forum.kurviger.com/0709/32/4699_2.png) [@0709](https://forum.kurviger.com/u/0709)\
**Post date:** [February 27, 2021, 1:23pm UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/31 "2021-02-27T13:23:11Z")

</div>

Hi Manfred.

Recalculate route - Next Waypoint - Fast to route: Unset

Local circuit attached:  
Design route as .kurviger. Detour as gpx.  
[Lo\_Lo.kurviger](https://forum.kurviger.com/uploads/short-url/cyh3hb0UUgGOFAulF55hglFW7tX.kurviger) (1.3 KB) [Zeveneken omleiding.gpx](https://forum.kurviger.com/uploads/short-url/3o4cB5dCURsP9Kuuqql3hicbBhb.gpx) (23.8 KB)  
Simulate by the Lockito app. Set @ 50kmh.

Favorable for the local detour. Third recalculate = Fwd. However, does not help for the Guglingen detour.

After second recalculation: Trigger set obstruction 500m.  
_That way you say: I don’t want to go back!_  
Notice:  
I report this as 180° turns, as the app does not report the try to return action to do.

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<div class="post-metadata">

**Author:** ![devemux86](https://forum.kurviger.com/user_avatar/forum.kurviger.com/devemux86/32/6239_2.png) [@devemux86](https://forum.kurviger.com/u/devemux86)\
**Post date:** [February 27, 2021, 8:16pm UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/32 "2021-02-27T20:16:59Z")

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> [@0709](#):
>
> I do report this as 180° turns, as the app does not report the U-turn action to perform.

Navigation / voice guidance works with the route / turn instructions calculated by the routing service.

Navigation can not announce artificial instructions.  
Like “Make a u-turn” when u-turns are not allowed.

Only routing service knows the road network and produce the turn instructions.

Routing service must first (re)calculate a valid route, produce the turn instructions  
and then they can be used in navigation.

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<div class="post-metadata">

**Author:** ![devemux86](https://forum.kurviger.com/user_avatar/forum.kurviger.com/devemux86/32/6239_2.png) [@devemux86](https://forum.kurviger.com/u/devemux86)\
**Post date:** [February 28, 2021, 10:56am UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/34 "2021-02-28T10:56:37Z")

</div>

_Please avoid the many edits for questions._  
_Edits do not send notifications and are lost._

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<div class="post-metadata">

**Author:** ![devemux86](https://forum.kurviger.com/user_avatar/forum.kurviger.com/devemux86/32/6239_2.png) [@devemux86](https://forum.kurviger.com/u/devemux86)\
**Post date:** [February 28, 2021, 11:02am UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/35 "2021-02-28T11:02:52Z")

</div>

A post was merged into an existing topic: [Navigation announcement incorrect when driving the wrong way](https://forum.kurviger.com/t/navigation-announcement-incorrect-when-driving-the-wrong-way/4989/5)

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<div class="post-metadata">

**Author:** ![0709](https://forum.kurviger.com/user_avatar/forum.kurviger.com/0709/32/4699_2.png) [@0709](https://forum.kurviger.com/u/0709)\
**Post date:** [March 7, 2021, 2:08pm UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/36 "2021-03-07T14:08:56Z")

</div>

I further checked the idea by some more slow speed (bicycle) tests.  
Mostly did use the offline BRouter @ a non high (medium) density road network.  
No city streets, where a smaller block area maybe could be more optimal.

Test Goal:  
Does the method do the job as expected ? = OK  
Is the method flexible ? (Changing mind) = OK  
No extra issues, no non escape loops, nor unexpected stop ? = OK

Principle:

- Moving in the forward route direction decreases the turn distance indication.
- Moving in the opposite route direction increases the distance indication.
- AFTER each recalculation, the app than checks the route distance change.  
(Manual simulated test was safely possible whilst moving @ slow speed)
- If the distance increases then generate an additional TTS msg: \*\*“Try to Return”.
- In case the distance increases (2) 3 times **AFTER EACH OTHER** , generate an obstruction.
- This way, without halting, you enforce an alternative after (200 a 300m) 300 to 400m.
- Escape so out of multiple identical recalculate msg’s whilst you keep further moving.

\*\*(_See therefore also the previous video inclusive subtitles!_)

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<div class="post-metadata">

**Author:** ![devemux86](https://forum.kurviger.com/user_avatar/forum.kurviger.com/devemux86/32/6239_2.png) [@devemux86](https://forum.kurviger.com/u/devemux86)\
**Post date:** [March 7, 2021, 2:22pm UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/37 "2021-03-07T14:22:39Z")

</div>

Please wait for next version that will not have the automatic 1st voice announcement  
and then we can check the whole situation again.

In any case, creating artificial road blocks is not a safe solution,  
as the only road network known to navigation is the route itself.

> [@Navigation announcement incorrect when driving the wrong way](https://forum.kurviger.com/t/navigation-announcement-incorrect-when-driving-the-wrong-way/4989/9):
>
> Thanks for the information, now it seems more clear what could happen. The (re)routing requests contain also the location’s heading (coming from GPS). Navigation gets the (re)routing response and auto-announces the 1st instruction. Navigation continues. If user keeps being off route then more reroutings happen. Automatic 1st voice instruction should probably be omitted and only the [programmed instructions](https://forum.kurviger.com/t/app-voice-instructions-frequency/2070) must be announced. (then such confusion can be avoided)

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<div class="post-metadata">

**Author:** ![0709](https://forum.kurviger.com/user_avatar/forum.kurviger.com/0709/32/4699_2.png) [@0709](https://forum.kurviger.com/u/0709)\
**Post date:** [March 7, 2021, 3:01pm UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/38 "2021-03-07T15:01:19Z")

</div>

> [@devemux86](#):
>
> Please wait for next version

Sure will do 😉

> [@devemux86](#):
>
> creating artificial road blocks is not a safe solution

**So far** did not find any negative in producing a block like that as the road block toggling change technique used by the Kurviger app is unexpectedly very flexible.  
Must say I was surprised to observe that, as this is very different as I was used too by that other app where all (multiple) such generated blocks are kept in memory for a certain time spam.  
Anyway it would be very usefull of course if also another person would test and confirm my findings.

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<div class="post-metadata">

**Author:** ![0709](https://forum.kurviger.com/user_avatar/forum.kurviger.com/0709/32/4699_2.png) [@0709](https://forum.kurviger.com/u/0709)\
**Post date:** [March 11, 2021, 6:03pm UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/39 "2021-03-11T18:03:45Z")

</div>

Virtual test by V 1.14.15.  
Test track Güglingen. Simulated the redirection as described by RHoffner.  
Talks a little less now, but if you just keep driving, still repeats 22 x Route recalculation.  
Only the 22nd time you do get the long-awaited forward alternative. (Kurviger online)  
Lets wait for real user experience reports ?

> [@0709](#):
>
> > [@devemux86](#):
> >
> > Automatic rerouting is overrated and can produce strange results in all navigators.
> 
> The barrier of the L1103 to Pfaffenhofen.
> 
> In order of preference.
> 
> 1. The most optimal: The barrier in Pfaffenhofen is indicated in osm. (Is not)
> 2. Manually indicate the blocking while you are still on the route, this where the detour starts at the L1110/L1103. (Didn’t happen).
> 3. Follow the detour and either manually or automatically as suggested you place a block on the returning L1110 route back toward the missed L1103.  
> You will get an alternative but you have to be very attentive because it may well be that an alternative will just bring you back to the still unblocked L1103.  
> Placing an automatic blocking on the L1110 where you do not want to roll back do prevent the multiple almost identical recaclulate commands .

---

<div class="post-metadata">

**Author:** ![devemux86](https://forum.kurviger.com/user_avatar/forum.kurviger.com/devemux86/32/6239_2.png) [@devemux86](https://forum.kurviger.com/u/devemux86)\
**Post date:** [March 11, 2021, 6:27pm UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/40 "2021-03-11T18:27:16Z")

</div>

> [@0709](#):
>
> Only the 22nd time you do get the long-awaited forward alternative.

The application understands that user moved away from the calculated route.  
It requests from routing service a new route, passing _user location + heading_.

If _routing service calculates a backward route_ that fails to navigate, what next?

I have explained above that _navigation is (advanced) mathematics_.  
Human perception and fuzzy solutions do not work with computers.

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<div class="post-metadata">

**Author:** ![devemux86](https://forum.kurviger.com/user_avatar/forum.kurviger.com/devemux86/32/6239_2.png) [@devemux86](https://forum.kurviger.com/u/devemux86)\
**Post date:** [March 11, 2021, 6:47pm UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/41 "2021-03-11T18:47:42Z")

</div>

[GraphHopper routing API](https://docs.graphhopper.com/#tag/Routing-API) (and Kurviger) support heading directions.

If I remember correctly BRouter does not support heading directions?  
(so the preferred starting direction of the route can be any)

Please check carefully the calculated (re)routes  
and reproduce them in Kurviger / BRouter sites.

If a routing service insists calculating a route,  
the app can receive and use it or ask a new one.

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<div class="post-metadata">

**Author:** ![0709](https://forum.kurviger.com/user_avatar/forum.kurviger.com/0709/32/4699_2.png) [@0709](https://forum.kurviger.com/u/0709)\
**Post date:** [March 11, 2021, 6:49pm UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/42 "2021-03-11T18:49:18Z")

</div>

Is just a report Emux 😉 as you probably do expect by Beta tests and this inclusive some of my own findings. Nothing more. And yes I do know this subject is certainly not an easy task for you the developper. Courage.

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<div class="post-metadata">

**Author:** ![devemux86](https://forum.kurviger.com/user_avatar/forum.kurviger.com/devemux86/32/6239_2.png) [@devemux86](https://forum.kurviger.com/u/devemux86)\
**Post date:** [March 11, 2021, 6:52pm UTC](https://forum.kurviger.com/t/navigation-stops-after-several-rerouting-attempts/4952/43 "2021-03-11T18:52:12Z")

</div>

> [@0709](#):
>
> And yes I do know this subject is certainly not an easy task for you the developper. Courage.

No problem, the interesting part is to turn all this into mathematics. 🙂  
(using the available tools)

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