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Jul 22, 2018, 09:17 PM
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Thread OP
Quote:
Originally Posted by ChilloutNobody
Hello all,

I was not testflighting it yet, because I noticed that I have not programmed the failsafe positions yet.

I started the Rx and TX. Then I moved the sticks and the buttons into the failsafe position like stater on the ulrs homepage. Then pushed the button on the tx.
After testing the failsafe on the bench I saw in the libre pilot software that the positions are in a completly different positions. After doing so for a few more times I recognized that I can't Programm the failsafe positions. In the ulrs cc I see that it goes into failsafe but the fc software just recognizes the stick positions. In that case it would go completly go berserk.
Throttle 100% and the other sticks to 0% and 100%.

Now my question... Am I doing something wrong?
Is the failsafe only for the APM/Pixhawk stack?

Greetings
There's a bug to save the failsafe positions, for the moment the best is to use the GCS failsafe.
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Jul 23, 2018, 04:39 AM
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babak_ea's Avatar
Quote:
Originally Posted by flipflap
There are many ways to display the RSSI, I've chosen a log scale, which is explained here : http://www.itluxembourg.lu/site/ultimate-lrs-rssi/

The advantage of this representation is that you can easily estimate the maximum range given the RSSI at any given distance.

Most other system have a percent value that doesn't have a real meaning (for example 50% doensn't mean you're at half the maximum distance).

45 at 200 meters means -55 dB at 200 meters.

Then check on the ULRS range estimator : http://www.itluxembourg.lu/site/wp-c...-estimator.pdf

And you'll see that it gives something like 30-40 km range with your antennas.

So yes a log scale has the disadvantage that it will drop quickly in the beginning (actually it will loose 6 points every time you double the distance), and then drop very slowly. But at any distance you'll be able to evaluate easily the maximum distance.
Thank you Ben, your explain was very clear and perfect.
but 45 at 200 meter display on mission planner, not on ultimate LRS control Center, dose it equal?
if yes, the result is my antenna is good, but I don't know which length is correct, 15.35 cm or 16.3cm
Last edited by babak_ea; Jul 23, 2018 at 04:51 AM.
Jul 23, 2018, 05:02 AM
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Thread OP
Yes it's the same.

If you ask me, 15.35 is correct.
Jul 24, 2018, 10:20 AM
Registered User
Ok,...
So the failsafe only works with the ardupilot GCS..
My software like libre pilot or openpilot can not handle this signal.
A great pitty

Greetings
Jul 24, 2018, 11:23 AM
Build more, websurf less
FlyingW's Avatar
Quote:
Originally Posted by ChilloutNobody
Ok,...
So the failsafe only works with the ardupilot GCS..
My software like libre pilot or openpilot can not handle this signal.
A great pitty

Greetings
ChilloutNobody,

The ULRS currently does not give any signal that can be used to trigger a failsafe.

The work-around is to use a flight controller and ground control system that exchange "heatbeat messages" on the telemetry link. With the ULRS working normally it will continue to send RC controls and mavlink telemetry. If the ULRS (or ground control system) fails then we know that the telemetry will be interrupted.

You program the flight control system so that if the airborne flight controller misses some number of heartbeat messages it declares a failsafe event. You have your failsafe strategy set for RTL, rally point, continue mission, etc.

This setup works well and I've seen work during an actual flight when I had a glitch with my bluetooth telemetry link from my transmitter to my GCS.

In my opinion however I did not like to have to abort a flight plan because of the loss of some telemetry packets. For this reason I wish that the ULRS supported a regular method to signal its failsafe.

If ULRS had this capability then it would pretty much be perfect.
Last edited by FlyingW; Jul 24, 2018 at 02:18 PM.
Jul 24, 2018, 02:44 PM
Registered User
Thank you for your tips!

Unfortunately the libre pilot software does not support this work around. It only supports Rx failsafe or when the Rx is sending kind of failsafe signature... Or so.. then I could Programm the failsafe in the cc3d
So there is no way where I can use the provided failsafe by the ulrs Rx.

Greetings
Jul 28, 2018, 09:38 AM
Registered User
Quote:
Originally Posted by narpat007
Hi, does it support bi-directional telemetry now?
I have been following this thread with great interest due to the fact that it uses LoRa radios which has very long range.
What I want is to use missionplanner as ground station to upload waypoints and issue commands from GCS only.
they are moving to Lora system (qlrz ) . Maybe ULRS will end soon if not change . No strange if it end same Olrs
Jul 28, 2018, 10:25 AM
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Thread OP
Qlrs has no bidirectional mavlink which makes it very different from ULRS. Two very different projects.
Jul 28, 2018, 10:53 AM
Registered User
Quote:
Originally Posted by flipflap
Qlrs has no bidirectional mavlink which makes it very different from ULRS. Two very different projects.
The end ULRS anyhow it also good system ago .
Jul 29, 2018, 02:43 AM
Registered User
Has this happened to anyone else? I launched ULRS Control Centre this morning (after not using it for a few weeks). The launcher went to download the latest version, and immediately Windows 10 Defender picked up a trojan virus:





I cleared the trojan, and tried again. Same result.

Scary
Jul 29, 2018, 06:10 AM
Registered User

Struggling with setup


Hi @ all!

So, I built my first URLS (Monkey Boards Tx and Rx), but now I'm struggling with getting it working.
Building and flashing was without problems, both modules configured with same parameters (channels 8,10,12,14,16, matching binding code on both, one as Tx, the other as Rx, 16 ch PPM, RSSI on ch 16), spectrum analyser works and Tx/Rx seem to talk to each other (all led's flashing).
But I never got usable Rc values, in ULRS CC the values were fluctuating all the time. Same in MissionPlanner, when the ULRS Rx was connected to an Ardupilot hardware.
OpenTX on my FrSky X12 Horus allows to change parameters for PPM output in the module bay. Tried different settings without success. Maybe a mistake here? Do I have to meet special requirements for PPM? Just ask'in because, if I pulled the PPM wire between ULRS Tx and transmitter the fluctuations stopped and I got stable readings on all 16 servo outputs.
Tried several things, re-flashing and re-re-flashing of both modules, different antennas, changed Rx and Tx, praying to different gods and finally a kind of rain-dance...

Any help would be appreciated!

Regards,

Kai
Jul 29, 2018, 07:01 AM
Registered User
Thread OP
Hi Kai,

So you've got everything working except PPM ?

What are your PPM settings on the RC transmitter ?
Jul 29, 2018, 07:02 AM
Registered User
Thread OP
Quote:
Originally Posted by zs6buj
Has this happened to anyone else? I launched ULRS Control Centre this morning (after not using it for a few weeks). The launcher went to download the latest version, and immediately Windows 10 Defender picked up a trojan virus:





I cleared the trojan, and tried again. Same result.

Scary
Yes, you've got to whitelist in Defender the folder where the launcher is executed. What it does (downloading an exe from internet) is interpreted as suspicious by Windows Defender.
Jul 29, 2018, 07:59 AM
Registered User
Hi flipflap!

Thanks for your quick response!
If you mean telemetry...no, I didn't test it yet. First I wanted to get the rc link working.
My actual PPM settings on the transmitter:
Mode: PPM
Channel range: Ch1-Ch16
PPM frame: 38,5ms / 300us / -

But this evening I gonna have BBQ with friends...so tomorrow I will do further attempts to get the system working...

Regards

Kai
Jul 29, 2018, 10:44 AM
Registered User
Thread OP
300 us that's fine, 16 channels too, so maybe the polarity is not correct, try the other polarity. Although you're the first one with this type of PPM issue.


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