Phantom 4 Emlid RTK/PPK



Continuing R&D on the use of Emlid GPS hardware for construction. Got the Emlid Reach M+ mounted and ready to test. I will run it in a traditional Base and Rover set up with the Reach RS+. If it works the package (excluding the P4P) will be $1200.

Phantom 4 RTK

The one unknown at this point is creating a repeatable way to ensure that the GPS transponder is precisely positioned… And yes I broke out a plumb-bob… :wink:


How well does the drone balance? Do you need to add a counter weight on the other skid?


We made the first steps with the kit a few days ago. First, we tested how exactly we could determine a known geodesic point on the ground. We left the drone with the kit for 45 minutes at this point (open, flat terrain without obstacles). Setting: Kinematic, Fix Hold). The PPK showed a difference to to the well-known coordinates of 25cm X axis, 1.2m Y axis and 4m Z axis at 16km baseline to CORS Station OAX2. After 30 seconds Fix-Solution which never broke again (99.9% fix).
After that we also hit the same point for 45 min with a Reach RS and did the same PPK. This gave a deviation of 3cm X axis, 4cm Y axis and 5cm Z axis. We think that this huge divergence between Phantom Kit and Emlid Reach RS is due to the inclination of the Tallisman antenna on the Phantom. After that we wanted to make the first flight, but the battery was empty. 90 minutes of battery life is very little for field trials. So our first recommendation: Take two or three batteries with you. However, we still flew a mission without switching on the Emlid M + to observe the stability of the Phantom. Very calm and stable flight behavior at first glance. This week we will do a test flight with Photoshooting.
But we are not quite clear how we can integrate the time delay into the PPK (for the moving drone) with RTK-LIB
All in all, we find this a good installation and are confident to get fixed the above mentioned deviation.