Point to Multipoint Connection to Multiple UAVs with single GCS

Hi.
I want to connect multiple UAVs those have RFD900x onboard to use as telemetry link.
Is there a way to connect these UAVs using a single telemetry modem (RFD900x) on the GCS?
Thanks…

As long I changed the SYSID_THISMAV to a unique number for each aircraft, I have been able to do this with both QGC and MP, without changing the firmware on the radios.

I also considered installing the Multipoint firmware per this document:

An interesting article here:

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Thank you for your reply.
But how did you separate the multiple data stream?
RFD900x is connected to the computer be seen as a serial device and a
serial device can only be opened one time.
How did you get this working with MAVProxy as connecting to a serial device multiple times?
Because this multiple data stream needs to be seperated from each other.

I did some experiment with MAVProxy and SITL using point to multipoint configuration of the modems.
First I started two SITLs using
arducopter -S -I0 --model copter --defaults /home/m/ardupilot/copter1.parm
arducopter -S -I1 --model copter --defaults /home/m/ardupilot/copter2.parm
Parameter files only holds the followings (individually):
SYSID_THISMAV 1.000000
SYSID_THISMAV 2.000000
Then i am connecting these SITLs using MAVProxy:
mavproxy.py --master tcp:127.0.0.1:5760 --out=/dev/ttyUSB1,57600
mavproxy.py --master tcp:127.0.0.1:5770 --out=/dev/ttyUSB2,57600
Where “/dev/ttyUSB1” is for SITL 1 and “/dev/ttyUSB2” is for SITL 2 individually.
And also the modem connected as “/dev/ttyUSB0” is P (center) of PtMP configuration.
And “/dev/ttyUSB1” and “/dev/ttyUSB2” are the MP (end nodes) of PtMP configuration.
Now i am running this command to open the center node:
mavproxy.py --master=/dev/ttyUSB0,57600 --out udp:127.0.0.1:14550
When i fire up above command i see some movement on the console of the individual MAVProxy terminals of the SITLs.
But when i want to seperate this communication via the following individual terminal commands:
mavproxy.py --master=127.0.0.1:14550 --target-system=1
mavproxy.py --master=127.0.0.1:14550 --target-system=2
Only the second one stays alive and other one breaks communication.
For example when i first do mavproxy.py --master=127.0.0.1:14550 --target-system=1, then mavproxy.py --master=127.0.0.1:14550 --target-system=2 on sepearate terminals, I am able to communicate with System 2 but not System 1.
But when i first do mavproxy.py --master=127.0.0.1:14550 --target-system=2, then mavproxy.py --master=127.0.0.1:14550 --target-system=1 on sepearate terminals, I am able to communicate with System 1 but not System 2.
How can i solve this issue?
Thanks…

@Mustafa_Gokce - The RFD900x connected to the ground station is capable of “listening” to several vehicles at the same time. The Ardupilot documentation suggests that you must have a separate radio for each connection, or use the multi-point firmware to accomplish multi-vehicle connections, but this doesn’t seem to be the case. I was able to track three vehicles with a RFD900X connected to my ground station, and a separate RFD900X in each vehicle.

Again, it is key that you change SYSID_THISMAV on each vehicle to a different number, but leave your ground station at the default. Both Mission Planner and QGroundControl were able to track all three vehicles in my test case. I am not suggesting it is the best or most efficient method, which Is why I included a link to the RFD manual which discusses the multi-point firmware and a link to an article where someone had used the multi-point firmware.

Hope this helps.

r

The modems support this operation but something is wrong in the MAVProxy (or i am missing something).

Interesting @wn0x , Was working on something similar myself, were you able to find max vehicle count that can be controlled at a time?

Are you all referring to Multiple Point to Point Setup with Sik Radio with single GCS?

Not Exactly, I was looking to connect multiple radios present in air to a single radio on ground with getting telemetry in GCS.

Good luck. How is it possible that the air radio and ground radio comes with an unique pair ID.

Unless you are referring to mesh wifi radio network for something like drone show.

Obsolete

Thanks Jai, that’s what I was looking for something similar to SwarmLink. I want to control multiple UAVs independently using a single GCS and without any communication between drone to drone.

I have a swarmlink kit.. never been used if you are interested