Trouble with PPK / Drone data

Hello people,

I have been testing PPK the last couple of months. The last time in a small mapping operations. After using the drone and base file, correcting the photo’s, the project was no more accurate than before correction. I have BTW corrected the .pos file, because number of photo’s was too high. I am sure I am making mistakes and of course dying to know what I do wrong. Would it be possible to upload my data here?

My equipment:

Emlid Reach RS
Emlid Reach M+
DJI Phantom 4 pro v2
Mettatec PPK set

Hi Remco,

Please share your dataset to support@emlid.com for analysis.

If your dataset exceeds 10 Mb, you can share just a link to a Google Drive or similar file-sharing service.

Thank you Andrew, I’ll send the data

Received, thanks! I’ll check it and get back to you soon.

Hi Remco, I’ve checked your dataset.

Extra photos
It seems like extra photos are taken during the ascent stage of the UAV. I think adjusting photo triggering settings on the UAV side should help you.

Lost time marks
I’ve also noticed at least one lost time mark. The gap is seen on the events track. Please double-check your setup according to our recommendations for Reach M+ configuration for mapping.

PPK
Regarding the PPK, I’ve got Fix for all events with the following settings:

  • Filter Combined
  • Elevation mask 15 deg
  • SNR mask 20 dB
  • Integer Ambiguity resolution GPS - Fix and Hold, GLO - ON

I’ve sent you the POS file by email.

Please note that the SNR on the rover looks lower than it can be. It hardly goes above 45 dB in some of the signals.

The Antenna or the cable may be affected by the hardware. You can check our recommendations on Antenna placement and Reach isolation in the Docs. It should help you improve the quality of the data.