here is a post to share the progress of setup 5 pairs OPENHD both video and mavlink telemetry in same LAN
Hardware Prepare
OPENDHD Ground (RPI 4B with a 4.3 inch screen, RTL8812eu as RF adapter, screen is not necessary here, but helpful for debugging, need proper heatsink, use simple custom PCB here)
5 group of ArduCopter setup(with SYSID from 1 to 5, Telem port connect to OPENHD air with mavlink protocol)
*RTL8812eu module doesn’t have FCC and CE certification
Issue to solve
release RTL8812eu driver not support scaning all 5.8G channel, thanks OPENHD team solved it during the progress
default OPENHD Ground only stream UDP H264 video on port 5600, mavlink UDP on port 14450(no need to change here) no params to change it, so have to build from source and add this feature
OPENHD development setup
use a x86 ubuntu 22.04 mini PC( security boot disabled on bios), not recommand to use your currently working ubuntu, I will use a plain new system here, I am mac user anyway
OpenHD has dep install script, so it’s quite easy to setup the build env, I will still coding on my mac and run gdbserver on ubuntu, so I can set breakpoints on my mac vscode
After success add the port configure feature, compile it again in RPI platform and add below params inside /boot/openhd/hardware.config
NW_FORWARDING_VIDEO_PORT = 5600
NW_FORWARDING_TELEMETRY_PORT = 14550
#5610 for sysid 1, 5620 for sysid 2 etc
Issue to worry
signal interference
PlanA just to use OHD1-5(total 7 in OPENHD link) for each pair
PlanB base on PlanA, use left/right spiral antenna pair(not verified yet, Plan A works)
Setup
5 ground and 1 PC will both connected to the same switch, I use my mac here and setup network share, so it will be 192.168.2.1 and also provide a dhcp server, all ground will screaming to 192.168.2.1, OPENHD ground need to setup Ethernet to “FORWARD + INTERNET”, using 5 gst-launch to display the video and qgc to connect the mavlink UDP, it works!
I would like to use the same link of OPEHHD(5.8G) and do mavlink RC, but not easy to find a RC style USB joystick, ELRS TX RC can do that role, but at this point adding another tiny ELRS RX to the drone make more sense, so the RC is ELRS with backpack, you can put another backpack TX to the drone and act as RX for “high power”
this is how the PCB looks like, if necessary I can share the KiCAD project, but just very simple PCB,air side shape to fit a pi zero stack, you don’t even need them if you can wire and install the module properly
