If I want to run python scripts to send and receive data from the ROV, I would have to run pymavlink on both the surface computer and the companion computer? Can someone please explain the structure of the connections (udpin, udpout)? Thanks.
pymavlink is already running on your ROV’s raspberry pi! It forwards mavlink packets between QGC on the topside and the Pixhawk. If you’d like to send and receive data from your topside machine, you can write a python script that will connect to the udp port opened by pymavlink and send and receive data from it. The documentation is a work in progress, but having just sorted through a lot of this myself, you might find the conversation on gitter useful.
As Tony described, we are working to improve our pymavlink documentation and examples, any feedback would be helpful
Let me know if you need any further help.
My best regards,