Reach RTK capabilities with Raspberry Pi

Hello,

I am planning to buy the Reach RTK setup, and use it in conjunction with my Raspberry Pi’s. As usual, 1 I will use as a base, and the other on a rover. Said rover will be 100% GNSS driven, so my question is how frequently and efficiently can I access the corrected position of the rover, from inside a script on the Raspberry Pi? I would assume I’d have to use a GPIO pin. Any clarification would be greatly appreciated.

Thanks!

I have a RPi 3 talking with my reach rover. I get 5Hz corrected signals over wifi, using a python script running on the pi.
Works like a charm. I see no need for a wired connection

older Pi’s may be a little more difficult if you don’t have Wifi.

How often can you get the corrected position from the rover? Is it like once every few seconds, or a steady stream?

The feepyj user said he gets 5HZ corrected signals over wifi. The formula for time is: T (period) = 1 / f (frequency). Therefore, Time (in seconds) = 1/5=0.2 seconds , That means he gets 5 readings every second or a reading every 200 milliseconds.

https://www.sensorsone.com/period-to-frequency-calculator/

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Maximum fix update rate is 14Hz, when using only GPS and some augmentation services (No Galilleo, Glonass or Beidou). I have a set up with the fix being output at 14hz over serial, I assume wifi data rates would be fine with this as well.

I get a new reading every 0.07 seconds, with maybe 1/5000 readings taking 0.14 seconds due to whatever reason.

@feepyj Hi, how is your setup?

Is the RPi talking to your vehicle via serial?
Is the RPi talking to the Rover Emlid via wifi?
Who makes the wifi?
how are you sending the positions and corrections? Everybody uses Mission Planner but I need for it to work without it, via wifi.

I have a router on the ground generating wifi for everybody.
My drone has an RPi3 conected via serial to the pixhawk.
The base is conected to the wifi, as well as the Rpi and the Rover on board the drone.
I want to land the drone on a specific remote marker, no telemetry, no RC radio, only the wifi.

any ideas?

RPi is not talking to the vehicle yet. (That’s a future step for me, it’s talking to a windows app that gives position guidance, but I manually steer the tractor to this target)

It is connected to the emlid over Wifi

I use a miniature router TP Link TL-WR802N as the Wifi hub

I get corrections from a NTRIP server over the internet. Reach gets them from from a wifi hotspot (via the TP link router).
Positions are sent out Wifi by the reach, I read the positions over Wifi using Sockets in a python program to get them into the RPi.

I think the only think you need to work on is getting the Base, Rover and controller all talking over Wifi. Assuming you will be in range for each. Then you can have RTK quality position data and use it for the landing.