They still making reference to the functionality.

JPAbdalla Posted at 3-25 10:52
They still making reference to the functionality.

Just received a new P4 RTK w/ D-RTK 2 and can confirm there is NO mobile device holder in the D-RTK 2 box.

Hello all, I'm having an issue my D-RTK-2 mobile base station. It automatically turns on when I put the battery in and I can't shut it down without removing the battery.  It also restarts itself about every 2 minutes. I am unable to us
e it. Any suggestions?

djiuser_K81ggRQpEh2O Posted at 5-6 05:38
Hello all, I'm having an issue my D-RTK-2 mobile base station. It automatically turns on when I put the battery in and I can't shut it down without removing the battery.  It also restarts itself about every 2 minutes. I am unable to us
e it. Any suggestions?

Sounds like the power switch may be stuck. If manipulating it vigorously doesn't solve the problem I'd say you need a service/repair ticket on the support site.

JPAbdalla Posted at 3-25 10:32
DJI just released this video on their Enterprise channel about setup for M300... I already commented there about the lack of the handheld functionality.

https://www.youtube.com/watch?v=-pzmpmiD9fs

I remember the same! TIRED of DJI releasing half baked products. After 2 years with no updates, the promised functionality of the D-RTK2 is another cheat from DJI to their clients!

Good afternoon everybody.
I own a DJI Phantom 4 RTK + D-RTK 2.
My query is, if somebody knows or can help me whit this...
If I buy another D-RTK 2 antenna equal to the one I have, does the 2-antenna system work as DIFFERENTIAL GNSS? Can I use one antenna as a BASE station and the other as a MOBILE to obtain, for example, control points in terrain surveys with the Phantom drone?
These 2 antennas work like any other DIFFERENTIAL GNSS system?
The query is to know if it is convenient for me to buy a DRTK-2 antenna, or if it is convenient for me to work with some other brand.
From already thank you very much.

GEOLOGIK Posted at 2-15 10:58
Good afternoon everybody.
I own a DJI Phantom 4 RTK + D-RTK 2.
My query is, if somebody knows or can help me whit this...

according to the D-RTK 2 User Manual, yes, this is possible (see screenshot below)



Haven't tried it myself though. And I wouldn't say the D-RTK 2 is the best bang-4-buck as far as RTK gear goes; it's overpriced and underfeatured. But you'll have a redundant proprietary base for your P4R I guess.

patiam Posted at 2-16 15:34
according to the D-RTK 2 User Manual, yes, this is possible (see screenshot below)

Thank you very much for the reply! I'll keep an eye on that-
Thanks

Hello I recently purchased the P4R and DTRK2. I took some saved points, In mode 3, after which i exported the saved points, Brought them up as a excel file,  Im looking at the data and for the life of me I cant figure out how they come up with the Altitude for these saved points. For example Point 1 is giving me an Altitude of 218.5863 ,I assume is in meters, but how is that figured out? Also when taking drone scans the Metadata, for each image, says Altitude is way higher then what I am flying at. Not sure on how the math works for this. If someone could explain it to me that would be awesome

Niklaus311 Posted at 5-3 11:55
Hello I recently purchased the P4R and DTRK2. I took some saved points, In mode 3, after which i exported the saved points, Brought them up as a excel file,  Im looking at the data and for the life of me I cant figure out how they come up with the Altitude for these saved points. For example Point 1 is giving me an Altitude of 218.5863 ,I assume is in meters, but how is that figured out? Also when taking drone scans the Metadata, for each image, says Altitude is way higher then what I am flying at. Not sure on how the math works for this. If someone could explain it to me that would be awesome

The altitude is in Height Above Ellipsoid (HAE). If you want it in orthometric height you need to apply the geoid separation for your location.
UNAVCO Geoid Calculator

https://www.propelleraero.com/blog/geoids-vs-ellipsoids-whats-the-difference/

See also this recent thread

Just reading thru this and to clarify, if I'm using the drkt2 stand alone, no bench marks, no know points, I don't have to add or subtract anything to the Z value?? The software calculates for you? Just let sit for 15 mins and connect p4rtk to it and fly mission, everything accurate then?

Slot Tech Posted at 3-8 20:28
Just reading thru this and to clarify, if I'm using the drkt2 stand alone, no bench marks, no know points, I don't have to add or subtract anything to the Z value?? The software calculates for you? Just let sit for 15 mins and connect p4rtk to it and fly mission, everything accurate then?

If you use the DRTK-2 in stand alone, you will not only have Z to correct but also X and Y.

If you want it to be really effective you have to place it on a known geodetic marker and enter the coordinates of this point  in your RC.  X and Y will be correct.  

For Z, whatever you do the drone will output an ellipsoidal altitude.  It's up to you to correct it in post process.  

From a personal point of view the DRTK-2 is not great, I talk about it in detail here: https://forum.dji.com/thread-285647-1-1.html

Slot Tech Posted at 3-8 20:28
Just reading thru this and to clarify, if I'm using the drkt2 stand alone, no bench marks, no know points, I don't have to add or subtract anything to the Z value?? The software calculates for you? Just let sit for 15 mins and connect p4rtk to it and fly mission, everything accurate then?

No. Non. Nyet. Iie.

So how is this used when you have no cell service for NTRIP and no known benchmarks? All I have is an open area in the middle of no where, nothing marked. Set up my DRTK-2, connect to my P4PRTK and fly while gathering non accurate data? Do I have mess with editing the Z value after it's shown sitting for 15 minutes before the flight?

High-precision GNSS measurements are made possible by application of Differential Corrections; that is, corrections that are the difference between the noisy measured value and the more precise corrected value. Whether one uses RTK or PPK, the source of the corrections must be relatively nearby (< 10 km is best) and its location must be precisiely known in order to produce the most accurate real-world results.
That's why you need to input precise coordinates for your on-site base station. Without its own source of corrections, its measurement of where it is (even after 15 minutes) is still probably ±1-3 m or more.

If you have no source of NTRIP and no benchmark on which to place your local (D-RTK 2) base, you have a couple options:

• Do what you've suggested. Your results will be internally consistent but may be shifted from real world coordinates by meters. You may be able to figure out the shift. If you have the means to get a precise location for a single GCP, you can figure it out. But it won't be consistent from setup to setup.
• I don't think this is possible w/ the D-RTK 2, but could be wrong. Install a survey nail or other marker or find a feature you can repeat exactly and set a "real" survey-grade GNSS base (Trimble, Leica, Emlid, Sparfun, etc.) up over it, log data for at least 15 minutes but not more than 2 hrs (for rapid-static) or 2-24 hrs (for static) and use OPUS or another method to PPK process the data and generate a precise set of coordinates for your marker. Then when you return to fly your mapping mission with the aircraft, you can enter those coordinates in the D-RTK 2. If you want the coordinates for the marker rather than the phase center of the GNSS antenna, you'll need to worry about antenna height.
• Just do PPK instead of RTK for your mapping missions.
  
  • Aerotas has a good workflow.
    
  In fact you should read everything they have to offer regarding using the P4 RTK.

Hope that helps. Good luck

LV_Forestry Posted at 3-8 21:11
If you use the DRTK-2 in stand alone, you will not only have Z to correct but also X and Y.

If you want it to be really effective you have to place it on a known geodetic marker and enter the coordinates of this point  in your RC.  X and Y will be correct.  

Or PPK with DRTK2. Be sure to collect at least 15m or more of data

patiam Posted at 3-9 13:47
High-precision GNSS measurements are made possible by application of Differential Corrections; that is, corrections that are the difference between the noisy measured value and the more precise value. Whether one uses RTK or PPK, the source of the corrections must be relatively nearby (< 10 km is best) and its location must be precisiely known in order to produce the most accurate real-world results.
That's why you need to input precise coordinates for your on-site base station. Without its own source of corrections, its measurement of where it is (even after 15 minutes) is still probably ±1-3 m or more.

agree.
There are a couple of free services in which you upload the rinex file of the drtk2 and they process for you

Thank You to everyone!!!!! I'm starting to understand all of this now.  

Guille_Meinero Posted at 3-9 15:00
Or PPK with DRTK2. Be sure to collect at least 15m or more of data

Do you have or know of a walkthrough or tutorial for doing PPK with logged D-RTK 2 data?

Guille_Meinero Posted at 3-9 15:00
Or PPK with DRTK2. Be sure to collect at least 15m or more of data

As Patiam wrote, in stand-alone mode, you can let it initialize for 2min, 15min, 15days... you shouldn't expect to have an accuracy of more than 30cm.  

Slot Tech Posted at 3-9 12:58
So how is this used when you have no cell service for NTRIP and no known benchmarks? All I have is an open area in the middle of no where, nothing marked. Set up my DRTK-2, connect to my P4PRTK and fly while gathering non accurate data? Do I have mess with editing the Z value after it's shown sitting for 15 minutes before the flight?

When Patiam refers to OPUS, it's the ultimate solution for jobs in the middle of nowhere. You can find a detailed tutorial here:

https://learn.sparkfun.com/tutor ... -base-setup--lasers

Thanks to everyone for helping me  I flew my first map today connected to the state dot cors network. I think everything went fine. I had RTK fix with a 22 and 23. When I downloaded my images, I see there are extra files included. I couldn't open them. What are they for and what do I do with them?

I uploaded the images to Drone Deploy.

You only need those files if you're going to do PPK or some other sort of post-processing. DD does not care about them, all it needs are the images with the getoag infomation embedded in their Exif data.

Ok, now I'm understanding things. Anyone use Emlid Studio for ppk. Looks like I can take those files on the drone SD card and download files from the DRTK-2 if used and make corrections to the inages that way. Any other free software or file converters out there I would find useful?

You've got part of the idea of PPK but not quite.

Yes, you can get better precision on your drone positioning by using PPK, but to do so you need to use base station files from another base besides your D-RTK 2, since it wasn't placed on known coordinates. So you'll want to find and download files from a nearby CORS (Continuously Operating Reference Station) to use for PPK. After doing so, you'll need to replace the realtime geotags in the exif image data with the new PPK-generated position info.

Besides Emlid Studio, look into RTKLib. Other folks here may have more suggestions.

patiam Posted at 3-9 16:07
Do you have or know of a walkthrough or tutorial for doing PPK with logged D-RTK 2 data?

I dont. You can use trimble ppk free service, works great, i think you need to register.
https://www.trimblertx.com/UploadForm.aspx
Download rinex files stored in your drtk2, and upload it to the service... in a couple of minutes you will have a report with coordinates in your email like the attach i just process
They recomend 60 minutes of records

..

LV_Forestry Posted at 3-9 22:12
As Patiam wrote, in stand-alone mode, you can let it initialize for 2min, 15min, 15days... you shouldn't expect to have an accuracy of more than 30cm.

5minutes of 15 days... standing alone any gnss (like drtk2) will get 2 o 3 meters.

If you want to get 2cm accuracy you NEED to correct the signal... i prefer RTK (here in argentina we have a network of corrections called Ramsac-NTRIP (with use internet to comunnicate). I login with the controller and correct the gnss of the drone directly without using DRTK2.

I just use DRTK2 when i dont have cell sevice. In that case DRTK2 to correct P4RTK and then in office PPK to DRTk2 to correct the whole project

patiam Posted at 3-10 20:49
You've got part of the idea of PPK but not quite.

Yes, you can get better precision on your drone positioning by using PPK, but to do so you need to use base station files from another base besides your D-RTK 2, since it wasn't placed on known coordinates. So you'll want to find and download files from a nearby CORS (Continuously Operating Reference Station) to use for PPK. After doing so, you'll need to replace the realtime geotags in the exif image data with the new PPK-generated position info.

you can use just DRTK2 to PPK and correct the whole project. No need of other GNSS

Guille_Meinero Posted at 3-12 10:06
5minutes of 15 days... standing alone any gnss (like drtk2) will get 2 o 3 meters.

If you want to get 2cm accuracy you NEED to correct the signal... i prefer RTK (here in argentina we have a network of corrections called Ramsac-NTRIP (with use internet to comunnicate). I login with the controller and correct the gnss of the drone directly without using DRTK2.

Why are you bothering with DRTK2?  If you have access to observations from a station not too far away.  PPK images directly.

I don't bother with drkt2. In fact i justo use ir 3 or 4 times a year

Guille_Meinero Posted at 3-12 10:09
you can use just DRTK2 to PPK and correct the whole project. No need of other GNSS

No, he can't use the D-RTK 2 data to PPK his concurrent P4RTK flight data, b/c the D-RTK 2 was not on a known location. He needs to use data from another base.

patiam Posted at 3-13 10:25
No, he can't use the D-RTK 2 data to PPK his concurrent P4RTK flight data, b/c the D-RTK 2 was not on a known location. He needs to use data from another base.

i have two methods:
Method A: better results, more time
1) Setup your DRTK2 in a well marked point and log data (no need to fly)
2) Process that rinex file with any online free services (like trimble's)
3) Re-setup your DRTK2 in the same point (and height) ...use corrected coordinates as known point and FLY

Method B: poor results, less time
1) Setup you DRTK2 anywhere but put a mark or control point under the DRTK2 in the field... the size depends of height drone will fly. Use the location it gives you the controller (it will be 2 or 3 meters error in absolute coordinates)... Be sure the DRTK2 is in the path or project of the drone. FLY
2) Process RINEX FILE and use it as control point in pix4d, metashape, etc... .I know... there is only one... but is better than nothing... it will correct the whole project, and, yeah... it works fine

Of course: you can use DRTK as a GNSS and survey several control/check points... remember to test and understand how long you need to achieve desire precision

Guille_Meinero Posted at 3-13 14:30
i have two methods:
Method A: better results, more time
1) Setup your DRTK2 in a well marked point and log data (no need to fly)

Your Method A is my Method 2 from this post (although I wasn't sure you could PPP D-RTK 2 data). What do you put for antenna type if it is asked for? Pretty sure neither RTX nor OPUS has it as an option.

Your method B, using the D-RTK-2 location as a GCP can work, but in the context of Slot Tech's question about PPK'ing his flight data using the D-RTK 2 data is not relevant.

But thanks for contributing, I think we all agree here

Does the Emlid Studio process any files from the DRTK-2 within its software? If so, whats the steps for it and what files do I need? Does the DRTK-2 store a Rinex file, or do you have to convert it from a different file that stored inside it?

patiam Posted at 3-13 14:40
Your Method A is my Method 2 from this post (although I wasn't sure you could PPP D-RTK 2 data). What do you put for antenna type if it is asked for? Pretty sure neither RTX nor OPUS has it as an option.

Your method B, using the D-RTK-2 location as a GCP can work, but in the context of Slot Tech's question about PPK'ing his flight data using the D-RTK 2 data is not relevant.

gonna try to upload a very simple step-by-step to ppk drtk2. Not perfect, it just works to me.
Method B... ok, maybe i didn’t understand exactly the scenario that Slot Tech's descript... what im trying to say is... if you flown with DRTK2, no matter is in a known -precise- point or not.... you can PPK drtk2 files (ok, these files NEED to be long enough)
And this takes me to a variant or method C that i didn’t describes b/c i was busy (and sure, as you guess, this is not my natural language) but I use it a LOT (when don’t have cell phone):
1)        DRTK2 anywhere, FLY (high precision, low accuracy). Take note of the DRTK2 position, this will be POINT A of the correction vector.
2)        Process with drone’s data as usual, you will get ortho and/or DTM as your input (high precision, low accuracy)
3)        PPK DRTK2 file, this will give you point B (between 2 or 3 meters)
4)        Move your ortho/dtm as the vector

Slot Tech Posted at 3-14 13:12
Does the Emlid Studio process any files from the DRTK-2 within its software? If so, whats the steps for it and what files do I need? Does the DRTK-2 store a Rinex file, or do you have to convert it from a different file that stored inside it?

yes emlid works perfect.. im gonna try to upload a quick guide

Quick guide to ppk drtk2 files
1)        Install emlid https://files.emlid.com/studio/w ... udio_v1.4_Setup.exe
2)        Locate the file you need stored in drtk2/ rtcmraw and copy to hdd, rename extension to RTCM3 (I know I said Rinex files, sorry, I use Trimble Business Center and convert files automatically)
3)        Open Emlid, choose Convert to Rinex, select the file. Now this is VERY important, you need to select the date of the drtk2 observation, you can get it from the name… in my case:
RTK246_202104141600_13ALG1D50500GH the date will be 2021-04-14. Convert

4)        A new folder with rinex files are stored, upload the bigger one (Obs file) to https://www.trimblertx.com/UploadForm.aspx and process

5)        After about 10 minutes you will get mail with a report
In my example:
A: S31°24'32.80161",W59°17'48.31980",71.030
B: S31°24'32.82141",W59°17'48.22154",72.536
Which is about 2.7m horizontal and 1.51m vertical….. that would be the shift to correct ortho/dsm

patiam Posted at 3-10 20:49
You've got part of the idea of PPK but not quite.

Yes, you can get better precision on your drone positioning by using PPK, but to do so you need to use base station files from another base besides your D-RTK 2, since it wasn't placed on known coordinates. So you'll want to find and download files from a nearby CORS (Continuously Operating Reference Station) to use for PPK. After doing so, you'll need to replace the realtime geotags in the exif image data with the new PPK-generated position info.

sorry, missed this post. Not agree, as i said before... if drtk2 is long enough you can use those obs files to ppk and correct, move or shift your raster.
Not saying is perfect or quick... just saying that is not mandatory the use of another gnss or a known point.

And, once again, i use this methods when i dont have internet access... which fortunately happens few times per year

Guille_Meinero Posted at 3-14 19:26
sorry, missed this post. Not agree, as i said before... if drtk2 is long enough you can use those obs files to ppk and correct, move or shift your raster.
Not saying is perfect or quick... just saying that is not mandatory the use of another gnss or a known point.

35 minutes of observations to do the PPP seems a bit short to me. Did you try to make a 35 minutes observation and a longer one without moving the antenna? To see if there is a big difference.

From experience doing OBS this short, you shouldn't expect anything better than +/- 15cm.

Which is not bad, if that's what the customer wants.