Fixing the continuous recalculation problem

[moeyhc]

Old issue re-visited.

To form a committee to look into the 'Recalculating problems' on dual carriage ways. Committee members will compile these roads into a data base to be post for re-tracking. These new tracks will be submitted to the mappers for investigation.

Our mappers are busy with new contributions and may not have time to work on these re-track routes. Hence we may need volunteers to help compile these tracks. Hope we can nail this problem once and for all.... cheers!

Major Recalculating routes I encountered
- Along the KL - Ipoh trunk road - N4 33.115 E101 07.018
- Along Jalan Kampar Ipoh (Jalan Raja Permaisuri Bainun) - N4 35.083 E101 05.282
- Along Jalan Bkt Gambir Pg - N5 20.247 E100 17.528

I volunteer to take up the compilation of data on Penang island if this proposal is approved.... cheers!

P/S:- Any guidelines from the Mappers are most appreciated.

[yc1437]

Hi bro may u show us some screenshoot how this problem happen?

Old issue re-visited.

To form a committee to look into the 'Recalculating problems' on dual carriage ways. Committee members will compile these roads into a data base to be post for re-tracking. These new tracks will be submitted to the mappers for investigation.

Our mappers are busy with new contributions and may not have time to work on these re-track routes. Hence we may need volunteers to help compile these tracks. Hope we can nail this problem once and for all.... cheers!

Major Recalculating routes I encountered
- Along the KL - Ipoh trunk road - N4 33.115 E101 07.018
- Along Jalan Kampar Ipoh (Jalan Raja Permaisuri Bainun) - N4 35.083 E101 05.282
- Along Jalan Bkt Gambir Pg - N5 20.247 E100 17.528

I volunteer to take up the compilation of data on Penang island if this proposal is approved.... cheers!

P/S:- Any guidelines from the Mappers are most appreciated.

[moeyhc]

I have the screen shot but could not find it. Basically on a dual lane highway your car will be traveling on the other side of the road. Some roads are more prone to this problem and it can be compounded with a De-tour.... cheers!

[chlesoh]

For the issue of non-stop recalculating, I have re-tracked some of those roads, I'm afraid it is not the accuracy of the map. I think it is more of the compactibility of the software with the map. It could be due to the some settings or programming which we might have overlooked.

[antyong (retired)]

Bro 76gpsguy had reported some interesting observation. Below is part of his report:

Hi antyong, I have continued the test to verify whether the endless route recalculation is caused by polyline direction setting for these few days.

The result of the test is as follows:
1) Dual carriageway routable 1-way polyline without direction setting
- Always encountered endless route recalculation at certain locations of dual carriageway.
- Unable to lock on correct carriageway when try to set new destination at dual carriageway area.
2) Dual carriageway routable 1-way polyline with direction setting
- Never faced any endless route recalculation problem at the above said similar situation.

I also carried out another test by shifting the alignment of the same dual carriageway to one side by one carriageway width. The test result same as the above test which is no more facing endless route recalculation with the setting of polyline direction.

Based on the above, we can conclude the following:
1) The accuracy of dual carriageway routable polyline alignment is not important and it will not cause the endless route recalculation problem.
2) Polyline direction setting is required for dual carriageway in order for GPS device to lock on the correct carriageway whenever there is any route recalculation occurred at dual carriageway area.
...

I have not verified this observation yet but I see the logic in it and am convinced we have a solution in hand. Will update further regarding this issue.

[alyem]

This issue was brought out before.. >>>The double-track dilemma

[antyong (retired)]

This issue was brought out before.. >>>The double-track dilemma

That is one of the cause but it seems now it is not the main cause.

[WeiQi00]

I still remembered, On 20th Nov, Garmin release new firmware v.3.70 for nuvi 200w, After I upgrade my Nuvi 200w taiwan version firmware from 3.30 to 3.70. On the road test, encountered a lot of Recalculation problem, I am no idea what is going on and revert back to v3.30.
Check on Taiwan forum mobile01.com, also has one thread talking about the new firmware 3.70 has this recalculation issued.
I think Garmin Taiwan has already received many complaint, on 2nd Dec Garmin taiwan release another firmware v3.80 to resolve this "recalculate problem". I hv already upgrade my nuvi 200w v3.80, on the road test, just few day testing and so far so good. Not yet encountered any recalculation problem.
I am just in doubt, whether firmware or Map will be caused this Recalculation problem ?

[rcmaps]

We had always from the beginning indicated direction on the polyline by ticking one way on the map display as well as the routing tab for dual carriageway lanes and have never had problems with this on the NZ maps.

Another cause which I stumbled on that caused recalculating was the fact that sometimes on our maps there were hidden sections or overlapped polylines. Perhaps a copy and pasted polyline added in error and very hard to spot unless you "move" the polyline aside to reveal if there is another polyline underneath, if nothing underneath, just click undo.

Worth a look.

[chlesoh]

"Polyline direction setting"... hmmm this sounds new to me as a user. Guess it is only known to the mappers or compilers.

That is why I've been suspecting it is more of map dependancy. However, I did notice 2 exceptionally interesting points:

1) On the same dual carriageway, if I were to make a U-turn (ie turn right & turn right) when it is suggested to go straight, then it will give the same erroroneous situation. But, if I were to turn left & turn left (U-turn onto the left side), then surprisingly it can adjust itself correctly!

This prompts me to think that it actually behaves correctly in a left-hand drive situation.

2) If I was put onto the wrong side of the road, despite still going straight, when it goes into another road indicating a different street name, then it adjusted back to my actual position.