Networking with raspberry pi, silent topic [closed]
Hi,
I've recently bought a Raspberry Pi 4. And I really want to use it to control my own robots. But for most applications I would like to have my Ubuntu virtual machine serve as a GUI for my robot. Therefore I need to have a working ROS network between my VM and my RasPi. All the instructions on the ROS Networking tutorial have been followed and I can ping and netcat between both machines. Since I don't have access to the tutorial's listener and talker on my RasPi I figured I could just use some basic rostopic commands to try out my setup. But when I attempt to echo a topic, this topic remains silent.
On my master device I have ran
roscore
and
rostopic pub -r 1 /plop std_msgs/String -- 'Hello slave'
both in separate terminals, of course.
On the slave side the master URI has been set :
export ROS_MASTER_URI=http://192.168.0.100:11311
And I can see the /plop topic :
bgi@ubuntu-VB:~$ rostopic list
/plop
/rosout
/rosout_agg
But when trying to listen to it, there's no message :
rostopic echo /plop
Bot my virtual machine and my Raspberry Pi are running ROS melodic and they can ping and netcat each other. Has anybody an idea of what is going on here, why can I see a topic but not listen to it?
