Anybody here using the RTK module with their Mavic 3 Enterprise? I've had my M3M for about six weeks now, but in the last two weeks its been unable to get an RTK connection (with one exception a few days ago when it worked). It just sits at "Converging", with strong signal and +/- 30 satellites. Any advice?

More details:

• I'm using a custom RTK base station (ZED-F9P feeding corrections through RTK2Go.com). The RTK2Go caster is up and running, and I connect the remote to my iphone hot spot.
• I can connect to it no problem - the RC Pro says "RTK connected. RTK data not in use.", and it'll have LLH and satellites listed below it, but no matter what I do I can't get convergence and therefore no launch.
• I've rebooted the base station, the controller, the drone, swapped batteries, waited hours/days to try later....no change
• I'm doing all of this on wide open prairies and clear blue skies, so there shouldn't be any interference/visability issues.
• I forget what firmware versions I'm running, but I did check and it was all the latest on both controller and drone as of last week.
  

My theory is the RTK module is faulty but man I don't know anything about this stuff - all I can say is it worked great for the first month but now it doesn't, and I didn't change any settings in between.

I've sent an email to support but maybe someone here has some suggestions?

RTK2GO + ZEDF9P for doing RTK is the winning combo for doing crap.

What type of antenna are you using?
Has the position of the antenna been measured accurately?
What messages does your F9P broadcast?
What is the brand of equipment that hosts the F9P, Ardusimple, Sparkfun...?

Have you tried disabling RTK, taking off, then re-enabling it once the drone is in the air? Obstacles on the ground generate this converging error. Trees, building...

Provided you are using a quality antenna with your F9P, you will save your time using the PPK method. Activates UBX_RXM_RAWX messages and logs them on an SD card via the Serial port. Or I2C if open.

Have you tried on a quality NTRIP network? RTK2GO is good for guiding a tractor, it is also made for that, but for surveying... It's a safe bet that your drone works very well.

Does the RTK status in DJI Pilot 2 show any satellites with your custom RTK source and that's position correctly?  Have you checked how many satellites your Zed f9p receiver is showing and how good reception for each - you can plug into the uCenter application to check, and you will also need to have configured the output settings on it to cast properly, depending on how you are actually doing that - you haven't mentioned what caster software and setup you are using which would be helpful to know.  I have a test GNSS base station setup with an ZED-F9P and a raspberry pi with RTKBase image which can send the data to various sources like RTK2GO (though not used that myself to cast to), emlid caster (have tested) etc or direct connection (on local network).  It would be worth updating the fimware on the Zed device as well, then check the required configuration settings, various guides for doing this on the internet through the ucentre app.

I would suggest to first try a direct connection to your caster (rule out any 3rd party caster config/other issue) so you know the caster is working locally first then troubleshoot with that next to see where your issue is.  I should add that I don't use an Internet caster directly as an RTK source, only for corrections to my GNSS base station, which in turn connect to from the RC Pro Enterprise (when I have mobile data signal to be able to do that).  I can then fall back to PPK processing if the RTK connection from my base station fails (as a wifi hotspot connection in the field between the GNSS base station and RC Pro Enterprise controller) that can happen or if some brief comms interruption between controller and drone). Hope that makes sense.

You could also try the NTRIP checker app on the rc pro enterprise controller directly to connect to your caster/rtk2go services to see if that shows OK with the location of the controller.

LV_Forestry Posted at 6-16 09:52
RTK2GO + ZEDF9P for doing RTK is the winning combo for doing crap.

What type of antenna are you using?

Yeah, I wasn't expecting survey grade results with this setup - I'm mostly using it to create boundaries and VR maps for the farm equipment so as long as accuracy is within a few inches I thought that'd be good enough.

I'm running Sparkfun equipment:
GNSS Multi-Band L1/L2 Surveying Antenna - TNC (TOP106)SparkFun Thing Plus - ESP32 WROOM (USB-C)
SparkFun GPS-RTK-SMA Breakout - ZED-F9P (Qwiic)

I did a PPP for about 12 hours to establish the fixed location of my antenna. Again, I assume it came out accurate - I'm new to GPS/RTK so I'm really counting on the Sparkfun tutorials to lead me true.

Messages - I just used the Sparkfun ArduinoIDE example, so its disabled NMEA sentences and is sending RTCM 1005, 1074, 1084, 1094, 1124 every second; 1230 every 10 seconds.

I've tried enabling RTK while 100m in the air just now and no change, but granted its an overcast day that might rain at any time...not sure if cloud cover is enough to block signals?

I haven't tried other networks, this was all intended to be a low cost/learning exercise really. I can set up Emlid as well I think...might be my next try.

Axelz Posted at 6-18 05:26
Does the RTK status in DJI Pilot 2 show any satellites with your custom RTK source and that's position correctly?  Have you checked how many satellites your Zed f9p receiver is showing and how good reception for each - you can plug into the uCenter application to check, and you will also need to have configured the output settings on it to cast properly, depending on how you are actually doing that - you haven't mentioned what caster software and setup you are using which would be helpful to know.  I have a test GNSS base station setup with an ZED-F9P and a raspberry pi with RTKBase image which can send the data to various sources like RTK2GO (though not used that myself to cast to), emlid caster (have tested) etc or direct connection (on local network).  It would be worth updating the fimware on the Zed device as well, then check the required configuration settings, various guides for doing this on the internet through the ucentre app.

I would suggest to first try a direct connection to your caster (rule out any 3rd party caster config/other issue) so you know the caster is working locally first then troubleshoot with that next to see where your issue is.  I should add that I don't use an Internet caster directly as an RTK source, only for corrections to my GNSS base station, which in turn connect to from the RC Pro Enterprise (when I have mobile data signal to be able to do that).  I can then fall back to PPK processing if the RTK connection from my base station fails (as a wifi hotspot connection in the field between the GNSS base station and RC Pro Enterprise controller) that can happen or if some brief comms interruption between controller and drone). Hope that makes sense.

Yup this is the part that confuses me. On RTK Status page it says "RTK connected. RTK data not in use.", then in the table it has the LLH and a bunch of satellites (28 in my screenshot). Under positioning it says SINGLE for aircraft, and blank under Custom Network RTK. Signal Strength is blank for both columns, and only the Aircraft column has any standard deviation listed.

I haven't plugged into U-Center since running the PPP to establish fixed location...I'll add that to my list of things to check when I have a minute. I used an Ardiuno (ESP32) to program the whole thing so didn't mess with any settings in U-Center, I assumed that was okay? Right now my setup is programmed to RTK2Go but I'll need to plug in to change to Emlid anyway.

chazawalla Posted at 6-18 09:59
Yup this is the part that confuses me. On RTK Status page it says "RTK connected. RTK data not in use.", then in the table it has the LLH and a bunch of satellites (28 in my screenshot). Under positioning it says SINGLE for aircraft, and blank under Custom Network RTK. Signal Strength is blank for both columns, and only the Aircraft column has any standard deviation listed.

I haven't plugged into U-Center since running the PPP to establish fixed location...I'll add that to my list of things to check when I have a minute. I used an Ardiuno (ESP32) to program the whole thing so didn't mess with any settings in U-Center, I assumed that was okay? Right now my setup is programmed to RTK2Go but I'll need to plug in to change to Emlid anyway.

If you've a raspberry pi do give RTKBase a go, it's got a web gui and easy to configure and see what's going on, that did need the device outputs configuring via ucentre so the software received the correct data. I also put the latest firmware on the device 1.32.  i just downloaded an image which someone had created off a link on the official site https://github.com/Stefal/rtkbase

chazawalla Posted at 6-18 09:54
Yeah, I wasn't expecting survey grade results with this setup - I'm mostly using it to create boundaries and VR maps for the farm equipment so as long as accuracy is within a few inches I thought that'd be good enough.

I'm running Sparkfun equipment:

So far your configuration seems to be optimal. How far are you from this station when you try to connect to it?

The top of the top with this equipment is to make PPK. The level of requirement for the receivers of DJI drones is quite high.
The weather has no major influence on the GNSS signals. Not enough to explain why a system finds a valid solution one day but not the next.

The things that will have an influence are:

-the distance from the base station.
-the presence of obstacles but if you say that you tried at an altitude of 100m, we can rule out this possibility
- network latency.
You can also do as Axelz recommends, update the firmware, but if the system has already worked I doubt that is the problem.

My safe bet: 1/ The base antenna has moved, the corrections are too bad to find a valid solution. 2/ you are too far away or the network has too much latency.

LV_Forestry Posted at 6-19 09:29
So far your configuration seems to be optimal. How far are you from this station when you try to connect to it?

The top of the top with this equipment is to make PPK. The level of requirement for the receivers of DJI drones is quite high.

Hmm... Is there a way to diagnose my RTK base station/NTRIP server or just to confirm its solid? I can plug into u-center, I'm just waiting on an extended USB so I can reach it from the computer.

I'm not against PPK but man, whats even the point of the RTK module in that case!

The antenna is permanently mounted to my roof, and at this point I'm trying to launch in my driveway so max 100 ft give/take away from the base station. The only thing I can think re: my hardware setup is the opposite end of my roof, there's an old TV antenna tower thats maybe 20 ft taller than where the RTK antenna is. Could that cause interference?

Finally...am I crazy or is this understanding kind of correct: getting stuck on converging suggests a drone/remote issue, not a base station issue which has its fixed location? Or is converging issues possible on both base and rover ends?

The point of having RTK module is that his name is misleading since it is also used to record OBS file in order to be able to use the PPK method.

Converging issue can come from both side. About the TV antenna on top of the GNSS one, i doubt it comes from that but who knows. It is so sensitive.

You can try with another NTRIP station, RTK2Go or the national/local CORS if it exist. You can also try by changing your antenna location.

You can use NTRIP checker available on Android and IOS store. You will be able to see if connection is successful and if RTCM is broadcasted correctly.

I havn't noticed you are not broadcasting antenna detail and time sync. Try this config :
1006 or 1005 if you have only ARP 0,2Hz
1008 0,2Hz Optional
1013 60s 0.016Hz The one which mostly can cause trouble
1033 0,2Hz
1074 1Hz
1084 1Hz
1094 1Hz
1124 1Hz
1230 0,2Hz

If it doesn't work, feel free to send me the mountpoint name so i can check what comes out.

Well this just keeps getting more frustrating, I modified my code to add 1008, 1013 and 1074...go outside to test one more time before loading that change and it connects right up - not even outside, but standing in the doorway because its raining.

The only thing that changed from this morning is that I charged the controller and drone battery up - which is the same thing that I'd done right before it worked the last time before this, too. Seems crazy to think that a full or fresh charge affects things? Idk man I'm getting desperate lol.

The weather's supposed to be better tomorrow so I'll try again, and if it doesn't work I'll try with the new RTCM messages and report back.
Edit:
Flew a mission this morning, it had RTK right away at launch (and fresh off the chargers), but somewhere during the first battery RTK signal went weak again. Its on the chargers again so I'm going to fire it up this evening with full charges again just to see if that somehow is correlated. Will reflash the ZEDF9P this evening, but if that doesn't work I guess it might be time to learn how to PPK.

I've also sent all the logs to DJI Support so maybe they'll tell me something new.

Could this be related? I plugged into U-center and this is all that appears in the status bar on the right - and the Satellites row would lose all satellites every few seconds like in second image. I don't understand the software enough to know if that means anything but seems like the F9P could be frequently dropping the signal maybe?

chazawalla Posted at 6-21 19:30
Could this be related? I plugged into U-center and this is all that appears in the status bar on the right - and the Satellites row would lose all satellites every few seconds like in second image. I don't understand the software enough to know if that means anything but seems like the F9P could be frequently dropping the signal maybe?

Activate NMEA PVT and GSV. Accuracy should appear and you must be able to see how many sat are in view. Switch everything to 1Hz. No need more

I have the same issue, but with a Matrice 210 RTK. I'm using an Emlid RS+ and I've tried connecting through a local link and through the Emlid caster service. The drone receives the correction signal with no problem, as evidenced by the display showing the position of the base. The deviation drops down to around 0.01 in x and y and stays there, but I never get a fix. It continuously says "data converging".

If I connect to rtk2go directly for corrections everything works fine. I can get a resolution in about 1.5 minutes. The problem is I need to work on sites where data network is unavailable, so need to use the Emlid as a base station.

Well I had three solid days of it working great with no change on my end...had just started assuming DJI Support had pushed a change through remotely maybe, now back to not working this morning.

On the RC Pro E under RTK settings - what does it mean when it says SINGLE under aircraft positioning? I know it its supposed to say fix (or similar) when its all functional.

chazawalla Posted at 6-24 09:59
Well I had three solid days of it working great with no change on my end...had just started assuming DJI Support had pushed a change through remotely maybe, now back to not working this morning.

On the RC Pro E under RTK settings - what does it mean when it says SINGLE under aircraft positioning? I know it its supposed to say fix (or similar) when its all functional.

Single = not connected to a NTRIP caster
Float = converging = connected but the solution is not valid
Fix = Connected and solution is valid

Check your network latency. I do not see any other possibility of failure.

LV_Forestry Posted at 6-24 10:40
Single = not connected to a NTRIP caster
Float = converging = connected but the solution is not valid
Fix = Connected and solution is valid

That could be it as I'm on a 20/4 down/up WISP which isn't known for good speeds, what would good latency be?

Speed test ping on my PC just now has 30 idle, 48 download, 350 upload...350 sounds like a slow number?
Edit: Google says anything over 100 is bad latency....so 350 upload could very well be the source of all this headache

LV_Forestry Posted at 2023-6-20 14:00
I havn't noticed you are not broadcasting antenna detail and time sync. Try this config :
1006 or 1005 if you have only ARP 0,2Hz
1008 0,2Hz Optional

hello LV_Forestry is it possible for you to give a quick overview on what protocols are required for DJI? I have a mount point that is broadcasting RTCM 3.2;1005(1),1074(1),1084(1),1094(1),1124(1),1230(1) but also having issues. I am using a ublox F9p module as the core of the base station and in u-center I can't (or just can't find where I) add other outputs.

quada Posted at 6-26 09:33
hello LV_Forestry is it possible for you to give a quick overview on what protocols are required for DJI? I have a mount point that is broadcasting RTCM 3.2;1005(1),1074(1),1084(1),1094(1),1124(1),1230(1) but also having issues. I am using a ublox F9p module as the core of the base station and in u-center I can't (or just can't find where I) add other outputs.

I can't post the complete syntax, this stupid anti-spam system has been reinforced recently.

So I ended up taking a screenshot because it's bothering me.