Displaying drifting buoys on OpenCPN?

[Jaco Versfeld]

Good day,


We need to deploy and retrieve drifting buoys for our research. I have been playing around with OpenCPN to help us with this task.



What would be the best way to display drifting buoys on OpenCPN? We have Lora + GPS enabled devices (Meshtastic network) where we obtain the GPS coordinates of every buoy - every 3 - 5 minutes. I have been toying with the idea to convert each buoy's coordinates to NMEA 083 AIS messages using Python, and then using a UDP / TCP port to feed these in as AIS targets on OpenCPN.


Is there maybe a better way to do it?


At the moment, we do not need normal AIS targets on the OpenCPN system displayed.


Thanks
Jaco

[bdbcat]

Jaco...


Welcome aboard.
Sounds like a good plan.


Good Luck
Dave

[Hakan]

I think a simple way is to send a NMEA0183 $xxTLL message to OpenCPN. See more about "TLL" here. A TLL message is more easy to program than a AIS VDM message.

Take the coordinates from the GPS and send position, a number and name for each buoy. Status = "T" will give a green target. "Q" a yellow.

The target in OCPN will be a circle with name and position like it's used for the radar plugin's ARPA targets, see picture. Track and course prediction will follow the preferences for a AIS target.

[Hakan]

Jaco..
btw:

You can also use $xxTTM. That's actually the one radar plugin uses:
Looks like this for a target on my pictures:

$RATTM,14,1.033854,353.250000,,9.66,278.4,T, , ,N,ARPA14,L, *3C