Inacurate track recording

[dougchesterman]

I've run Orux v7.4.26 on my S5 for some years, and it's by far my favourite GPS app. I've recently upgraded to an S22 and installed the paid-for version (v10.5.0), and the track recording is very inaccurate - looks as though a child has scribbled all over the map! However, if I run a second GPS app at the same time (Memory Map for All) then Orux works beautifully. Very Strange, and if anyone has any ideas I'd be grateful.
I've put v7.4.26 on my wife's S22 (identical in all respects to mine) and it works as it should without requiring MMfA also running. GPS Test on my phone reports good satelite reception.
I've attached an image with 3 track plots - the first is with V10.5.0 running alongside MMfA and follows my actual route to within a few metres. The next two are with Orux running on its own.

[Ivan_S]

Hi to all,
I'v got the same problem, I'm using Oruxmaps v 10.5.0 GP on a Motorola g73.
I worked fine for few months, then it began to generate very poor tracks, strongly deviating from the real path. It often stops recordering for a while or completely. The stuck problem sometimes is non solved even closing the app, switching off and on again the GPS and even switching off and on the phone.
I finally tried erasing and re-installing Oruxmaps, ma nothing happened.
The app is now useless.
Any idea on how solve the problem and how it can be tested if the origin of the malfunctioning is due to the GPS receiver or to the app?
Thank you in advance
Ivan

[dougchesterman]

I seem to have resolved this issue myself by setting Sensors>GPS>Minimum time to 0 (always).
I think that what was happening is that calculating a GPS position involves a series of itterations, with the last position usually taken as the starting point for the next. The first position calculation could take anywhere as its starting point and is usually much less accurate. (I noticed that when Orux is started it takes a few seconds for the position to settle to the correct position.) I suspect that with Minimum time set to anything other than 0, Android(?) is shutting down the GPS completely so that GPS starts every position calculation from scratch, and is therefore giving big errors. When I had another GPS app running, this may have been keeping the GPS active so avoiding the issue . The problem might also be related to the S22's rather aggressive power saving (it doesn't have a very large battery.)
I'd be interested if anyone has any comments on my theory? Also, is this a problem which the Orux developers might have a fix for (I'm now worried about the implications for battery life...)

[Ivan_S]

Hi Doug,
I'll try your settings, but from many years I have always used 2 to 5 seconds as minimum time for GPS and it always worked well, with different Oruxmaps and Android versions and phones.

As far as I know all the GPS devices need an extra time when switched on, not only app-based smartphone, because they have to check many satellites, therefore I don't think that setting to 0 or 2 second could affect this behaviour (initial points oftyen shows large error, especially in elevation), but it is sufficient to wait 1 minute or so before starting track recording.
Anyway, as written before, I've recently also experienced repeated locks of the app, not only poor o stuck recording.

I'm asking again, not to you, about the existence of apps or tests for checking the origin of the problem (app, firmware, hardware ...)
Ivan


 

[ut]

Hi Doug,
I would timidly suggest checking your phone settings:
- none battery optimization for Oruxmaps
- Oruxmaps must be able to run in the background
- Oruxmaps must be able to access the GPS always and not only during use

Thinking about the app another test could be to export the user profile you have with v7.4.26 
and import it and use it in new v10.5.0

[dougchesterman]

Hi ut - Thanks for your suggestions. When I checked I found that the settings you suggest (battery optimisation/background running/GPS always on) were already set as you suggested - I've tried most of the obvious settings in my efforts to get Orux to run properly! As suggested I also downloaded the v7 profile from my S5 to v10 on my S22. I did the usual walk around the block with both the S5 and S22 tracking the walk (both now with the same profile), and while the S5 worked fine, Orux scribbled all over the map on the S22. However, Minimum time was set to 8sec on this profile, and when I set it to 0 (always) the S22 worked beautifully. It seems that this setting is essential for me.

Thanks also for your thoughts Ivan. Agreed that first positions when GPS is started are always inaccurate. My contention is that with Minimum time set to anything other than 0 (always) Android on my S22 is shutting down GPS completely between track-points, so that every point recorded is a first point. No idea how to confirm this idea though....

[orux]

Hi ut - Thanks for your suggestions. When I checked I found that the settings you suggest (battery optimisation/background running/GPS always on) were already set as you suggested - I've tried most of the obvious settings in my efforts to get Orux to run properly! As suggested I also downloaded the v7 profile from my S5 to v10 on my S22. I did the usual walk around the block with both the S5 and S22 tracking the walk (both now with the same profile), and while the S5 worked fine, Orux scribbled all over the map on the S22. However, Minimum time was set to 8sec on this profile, and when I set it to 0 (always) the S22 worked beautifully. It seems that this setting is essential for me.

Thanks also for your thoughts Ivan. Agreed that first positions when GPS is started are always inaccurate. My contention is that with Minimum time set to anything other than 0 (always) Android on my S22 is shutting down GPS completely between track-points, so that every point recorded is a first point. No idea how to confirm this idea though....

When minimum time is set to zero seconds, the GPS is on all the time.

If you use a value of 8 seconds, then Android can stop the GPS chip some seconds, to save battery. With two seconds, in the past the chip did not turn off either. But this now depends on the manufacturer. It is very possible that after 5 seconds it will turn off.
This is the reason why the accuracy is better using zero seconds.
The downside is that it uses more battery. That's why it's not free

orux

[Ivan_S]

Dear Orux,
nice to hear from you.
Your explanation could be correct about dougchesterman's troubles, arised from a new cellphone, but what about my similar problems of poor tracking with a phone that worked well for months?
From two months now it is simply impossible to get a tracklog, as written before I tried all the possibilities, including reinstalling the app.
Any ideas about that?
Is it possible  in some way to check if the GPS sensor works, in order to exclude an Oruxmaps role in mulfunctioning?
Thank you in advance
Ivan

[orux]

Dear Orux,
nice to hear from you.
Your explanation could be correct about dougchesterman's troubles, arised from a new cellphone, but what about my similar problems of poor tracking with a phone that worked well for months?
From two months now it is simply impossible to get a tracklog, as written before I tried all the possibilities, including reinstalling the app.
Any ideas about that?
Is it possible  in some way to check if the GPS sensor works, in order to exclude an Oruxmaps role in mulfunctioning?
Thank you in advance
Ivan

The app has no way of knowing if the GPS is working well.

Make sure the minimum time is at zero.

And disable the fused location provider in the sensors settings > GPS. This is used to use other location sources, in addition to GPS (from Wi-Fi networks, for example). Sometimes it may not give good data.

orux