I am from Türkiye and using a DJI Mavic 3 Enterprise UAV with an RTK module onboard on a photogrammetric site. I’ve planned two different flight missions from 30 m vertical height using two options:
1.A flight route using a ground GNSS station on a known position and connecting the UAV RC module via Wireless connection,
2.Same flight route without a ground station but connecting the UAV RC module via a smartphone’s mobile internet connection to a Regional CORS Service (TUSAGA-AKTIF).
I’ve gathered a few hundred digital images for each flight and processed them using Pix4D mapper. I didn’t change the input coordinate system (WGS 84) but defined the output coordinate system as TUREF / TM36 as usual.
After the full process of these flights, I digitized two specific points from each model using the point cloud and corrected the positions from their related images.
Differences
Y (m) X (m) H (m)
-1.077. 3.788. -0.099
-1.088. 3.804. -0.247
There seems to be a huge coordinate shift between these two flights, so I revised the images and their accuracies on each axis but there seems to be not a huge gap between them.
For RTK flight, accuracies vary between 1-2 cm and for Network-RTK accuracies were around 2-20 cm. Also, the RTK was fixed for each flight.
I also checked the onboard positions of the original images, because the same flight route was used. Initial positions are very close to each other as expected.
Depending on these values, calculated differences are beyond the expectations.
I was working on this issue and changing the parameters, like input/output coordinate system, geometrically verified matching, etc. But cannot find a solution for those differences.
Any help would be appreciated.
1.A flight route using a ground GNSS station on a known position and connecting the UAV RC module via Wireless connection,
2.Same flight route without a ground station but connecting the UAV RC module via a smartphone’s mobile internet connection to a Regional CORS Service (TUSAGA-AKTIF).
I’ve gathered a few hundred digital images for each flight and processed them using Pix4D mapper. I didn’t change the input coordinate system (WGS 84) but defined the output coordinate system as TUREF / TM36 as usual.
After the full process of these flights, I digitized two specific points from each model using the point cloud and corrected the positions from their related images.
Differences
Y (m) X (m) H (m)
-1.077. 3.788. -0.099
-1.088. 3.804. -0.247
There seems to be a huge coordinate shift between these two flights, so I revised the images and their accuracies on each axis but there seems to be not a huge gap between them.
For RTK flight, accuracies vary between 1-2 cm and for Network-RTK accuracies were around 2-20 cm. Also, the RTK was fixed for each flight.
I also checked the onboard positions of the original images, because the same flight route was used. Initial positions are very close to each other as expected.
Depending on these values, calculated differences are beyond the expectations.
I was working on this issue and changing the parameters, like input/output coordinate system, geometrically verified matching, etc. But cannot find a solution for those differences.
Any help would be appreciated.
