ROS2 Communication Issues between Ethernet and FOXY

[Jeffrey Mao]

Hi Modalai,

Currently, we are having trouble connecting to the drone while the drone is connected to the WiFi Network, and we are connected to the wifi network through the Ethernet along with some other communication lag between the drone and our laptops. We can connect to the drone if our laptop is on WiFi network and the drone to the WiFi network desptie it being a bit slow

Is there any specific settings that ROS2 has have for communications that need to be implemented on the drone to enable the communications on speed up communications in ROS2.

Thanks

[Jeffrey Mao]

To Continue on this thread, everything is fine if connect both the VOXL2 board and laptop to Ethernet, but not VOXL2 board to WiFi and Laptop to Ethernet.

[Zachary Lowell 0]

I will look a bit more into this - so when you log into the router is the voxl2 still on the network and is assigned a LAN from the router? Can you still ping the voxl2 from the parent computer when the configuration is the one above. I will troubleshoot this and return with a fix.

[Zachary Lowell 0]

@Jeffrey-Mao I am unable to recreate this issue - can you describe a bit more how ROS2 is playing into this? I have tried all permutations of voxl2 on wifi with dongle vs ethernet cable and my parent computer on wifi vs etherenet - I am always able to ping the voxl2 just fine on its LAN.

What do you mean by "connecting to the drone" - are you sure the voxl2 is in station mode and not SOFTAP mode? AKA it isnt creating its own WIFI signal. When the voxl2 is on wifi, how are you setting that up? Are you adb into the voxl2 and running voxl-wifi station WIFINAME WIFIPASSWD

Let me know.
Zach

[Manohari Goarin]

Hi @Zachary-Lowell-0, I work with @Jeffrey-Mao on ROS2 and Voxl2 at the same lab. Thank you for your help on this issue!
This is an update and additional details on the problem:

• We tested 4 different setups:

1. both laptop and voxl2 drone connected to Wifi,
2. both laptop and drone on ethernet,
3. laptop on ethernet and drone on Wifi,
4. drone on ethernet and laptop on Wifi.
   We connect to the drone from the laptop via ssh. The Voxl2 is in station mode.

• For all setups, the laptop and the drone can ping each other.
• We launched a simulation on the drone and published topics. The problem appears when we try to see the messages on the laptop (with ros2 echo). The messages from our topics are not visible, only in configuration 3. However we can echo the /fmu topics. All other configurations are fine.
• We launched a simulation on the laptop and tried to see the topics and messages on the drone. Everything is visible and fine.

Is there a limitation on the number of topics/messages that the drone can send?

Thank you in advance for your insights!

[Jeffrey Mao]

For a final wrap-up, we installed ROS2 Humble from Source on Voxl2 this fixed the communication issues.

We also noticed in Foxy if we we had the following set up on the same device

Publisher A -> (TOPIC A) Subscriber A (Which Publishes Topic B )

Topic A publishes 500Hz
Topic B publishes at 400Hz ish

In Humble,

Topic A publishes 500Hz
Topic B publishes at 500Hz