I was trying to connect to my real robot in one of my rosjects and i executed the indicated command in my robot to install RRL client. After that i followed the instructions of running ‘source ~/.bashrc’ and when i run roscore i got the following error:
"RLException: Unable to contact my own server at [http://master:36619/].
This usually means that the network is not configured properly.
A common cause is that the machine cannot ping itself. Please check
for errors by running:
ping master
For more tips, please see
http://wiki.ros.org/ROS/NetworkSetup
The traceback for the exception was written to the log file"
Before installing RRL client my roscore run without any problem. Can someone help me?
Thank you for your patience. This error may occur mostly due to firewall restrictions.
I’ve just reproduced it blocking UDP ports using ufw, a common firewall in Linux.
Could you check if you have any firewall running in your raspberry?
After disabling it, remember to restart the theconstruct.rll service and source the workspace again.
I’ve been all the week on a job trip so I did not have access to my Rpi until today, that’s why I did not answer before.
Finally I have been able to run roscore after installing theconstruct.rll i needed to update some packages before. I have done what it is stated in the video remote robot with ROSDS - YouTube and it looks like I’m connected to the robot (see image below) however when I open a terminal in my project and type rostopic list to check if i can see the topics running in my robot y get an error message “ERROR: Unable to communicate with master!”
I don’t know what could be happening, the instructions of the video are really straight forward but it is clear that something is not working as it should be.
Thank you for the details, yet we don’t have the information about firewalls.
Could you check if there is any blocking rules in your robox linux?
You can check with the command
sudo ufw status
If the robot does not have any firewall rules, it is important to make sure the network it is connected also allows it to connect to external networks. It uses to happen behing universities or some companies networks
Sorry for the late replay, but i am coming with really good news. After upgrading some packages and running again the command to install everything related with “The construct” the /etc/hosts file got updated correctly and i am able to connect to my robot from my rosject.