Unit 1: Rviz not displaying on local system as seen on course

I am attempting to replicate the online environment on my local system, which is running ROS Melodic.

I have followed the tutorial closely and carefully, having downloaded the files used in the course, but when I attempt to run step 3 of example 1.1:
roslaunch turtlebot_rviz_launchers view_mapping.launch
from Unit 1 in the ROS Navigation in 5 Days course, the laserscan and map topics do not work as expected on Rviz.

Provided is a screenshot of what is supposed to happen (from the online tutorial), and another of what actually happens on my local system can be found here (the first being the Rviz from the tutorial and the second being the replicate on my local system)

Due to the fact that I have not edited the files from its original state, I have come to a conclusion that it may be due to the difference between the ROS version used online (Noetic) and the one on my local system (Melodic). Please let me know if you have an alternative idea!

The GitHub repository hosting the code can be reached at this link

Hi Patrick,
it could be due to differences between Noetic and Melodic, but let’s take that option as the last resort (because usually, when that is the case, you would not get so far as having the robot in rviz).

1st obvious question: have you installed all the required packages for Navigation in your system? If not, go for it
2nd question: are you using our simulation fro our public repo or is it a simulation of your own
3rd point: please post here the output messages that you get in the terminal that you launched navigation. That is the key to know what is the error about
4th point: have you checked if the laser is publishing data? By looking at your screen capture, it doesn’t look like it is publishing. Make sure it is publishing by using the rostopic echo command

Well, there is a lot to debug in there because the conditions in your machine can be anything. Let’s start with those questions and progress from there

Hello Ricardo! Thanks for responding :smiley: Following up on your advice:

  1. Yes, I have successfully installed all the required packages for the ROS Navigation Stack.

  2. I was able to download the whole of the course’s online directory, and have been running the simulation on the local system using the same files as if it were online. However, I was unable to find the public repo for the ROSNavigationIn5Days Course, could you please refer me a link to it ?

  3. The only output messages (other than initialization of nodes) presented were when running
    roslaunch turtlebot_navigation_gazebo gmapping_demo.launch and
    roslaunch turtlebot_rviz_launchers view_mapping.launch
    I have linked the terminal output here

  4. After running rostopic echo -n 1 /kobuki/laser/scan, the topic can be seen to be publishing data, I have attached a screenshot below:

Thus, I am quite lost here :sweat_smile:. Any guidance or clarification would be appreciated, and please let me know if you need anything else!