The products tested
Drone prices are rising significantly and people are searching for the most affordable option that also gives the best results. It's all about the price-performance ratio now. To help you make the right decision we decided to test the Autel Evo 2 PRO-RTK drone, which has similar specifications as DJI Phantom 4 RTK, except it has a rolling shutter while Phantom RTK has a global shutter, yet it costs 20% less than its competitor (at the time of analysis).
To test our Autel drone we received two datasets from our customers. The first flight was done in Portugal’s suburbs and the second at a lumber company in Lithuania. This way we were able to test the drone in two very different circumstances. To measure the accuracy, we set 1 GCP point and 4 validation points. Normally we suggest using 4 GCPs, but as we were only testing the drone we used one.
The area we covered in Portugal was about 1,53 hectares (3.77 acres) big and we made 461 images to cover it.
The area covered in Lithuania was about 10,55 hectares (26.06 acres) and we made 840 images.
In Portugal, we used the double grid path of the drone, as it gives the best results, while in Lithuania we used the regular single grid path. After that, we returned to the office and opened 3Dsurvey. We loaded the images and imported telemetry data. After that, we started the bundle adjustment step. When it was finished, we went straight to the orientation step where we did the orientation with GCP data, where we set one target as GCP and others as validators. After centering the points, we got our results.
The first table shows the accuracy of results in Portugal:
The second table shows the accuracy of results in Lithuania:
Based on the analysis we did our point cloud accuracy in Portugal was 3.7 cm and our point cloud accuracy in Lithuania was 2.4 cm which is vastly precise. Also, if we made even more pictures of the area, we would be able to get even better results, but in this case, it wouldn’t be necessary.
Vid Peterman & Ivan Žan Barbarić