How to add RTK to my drone

I enjoyed the Sparkfun article “Setting up a Rover Base RTK System” and I plan on building one, specifically to use for accurate drone mapping. I just do not know how to do that. Do I need another ZED-FP9 board and antenna for my drone? How do I set this system up so that the two talk to each other while taking the mapping photos? Do I need to sync the RTK’s 1 HZ location info to trigger the camera somehow to cross-reference the location information to the picture? There are commercial drones that have this functionality but to me the whole purpose is to replicate this as a DIY project.

Has anyone else done this? If so, where can I go to learn your solution and workflow?

Another use case I want to try is for a RTK Base rover feeding location information to a lawn mower so it methodically mows my lawn in a crisscross pattern like I mow, not some random bump and move process with an electrical dog-fence in my yard. There is a YouTube video of a person in Europe that did this and it is called the OpenMower Project.

Thanks in advance.

You need an RTK Drone from factory, and a base that can be a sparkfun surveyor, express or even facet.

If you don’t have an RTK drone (from factory) and want to acheve high precision derliverables, you can take GPCP’S with a base a rover setup, that way you can recify your pictures in the software you use to process data, and therefore your project is gonna be in the centimeter pecision range

It can be done…see https://ardupilot.org/copter/docs/commo … -page.html to start, lots of drones flying with RTK. I did my tests using two Sparkfun F9P modules. One as a base with a RF backhaul to the drone’s F9P, which functions as the drone navigation GPS and processes the RTCM correction from the base.

Alternately, some folks pass NTRIP corrections from a tablet or PC to the RTK GPS in the drone, again via a RF backhaul - WiFi,

BLE, etc.

It takes some setup and testing, but I can tell you lots of drone guys are doing it. There are a lot of posts re:RTK/drones in the Arducopter forum, here: https://discuss.ardupilot.org/ . Just enter RTK in the upper right search box.

Have fun! John

ABNormal1960:
There are commercial drones that have this functionality but to me the whole purpose is to replicate this as a DIY project.

Likewise. I want to learn by doing, not buy buying it off the shelf. I’m starting off with a DJI Phantom 4 Pro V2.

ABNormal1960:
Do I need another ZED-FP9 board and antenna for my drone?

Yes, maybe one for the base unit, the other for the rover (drone). I’ve DIY’ed a Base Unit with a SparkFun GPS-RTK2 Board - ZED-F9P GPS-15136 and a GNSS Multi-Band L1/L2 Surveying Antenna (TNC) - TOP106 GPS-17751. I’ve also ordered a SparkFun RTK Facet GPS-19984. It will be easier to setup in the field. For the rover/drone side, I’m still debating if in addition to a second ZED-F9P board, I need dead-reconing features if there’s a failure to receive GNSS. If so, I will probably add an ESP32 processor so that I can add additional sensors. I will use a GNSS Multi-Band L1/L2 Helical Antenna (SMA) BT-560 GPS-17383.

ABNormal1960:
How do I set this system up so that the two talk to each other while taking the mapping photos?

I’m using the SiK Telemetry Radio V3 - 915MHz, 100mW from Sparkfun (In stock WRL-19032) 915MHz has far better range than Bluetooth Classic, BLE extended range or WiFi. Furthermore, I don’t want to interfere with my P4P’s telemetry on 2.4GHz. The drone will also need a Remote ID device also on Bluetooth/WiFi to be able to fly past Sep 2023.

ABNormal1960:
Do I need to sync the RTK’s 1 HZ location info to trigger the camera somehow to cross-reference the location information to the picture?

At this point, I don’t know if connect my F9P board instead of the internal GPS or if I operate both in tandem. I still have not answered the RTK versus PPK argument for myself.

I’m working with a guy on E-Bay that 3D prints antenna and camera mounts for attaching all of this to my P4P

His ad “DJI Phantom 4 GNSS Antenae Up/Down on Front /Rear shown on down/rear NEW ITEM”