Rqt_gui , Rqt_console | Debugging tools | Webots ROS2 Tutorials | [Tutorial 9]

Wish to create interesting robot motion and have control over your world and robots in Webots? Soft_illusion Channel is here with a new tutorial series on the integration of Webots and ROS2. (A channel which aims to help the robotics community).

#ros2_debug #rqt_graph #rqt_console
Video series:
1. ROS 2, Webots installation and Setup of a workspace in VS Code
2. Different examples in Webots with ROS2
3. Use ROS2 services to interact with robots in Webots
4. Control a robot with ROS2 Publisher
5. Get feedback from different sensors of Robot with ROS2 Subscriber
6. Implement Master and Slave robots project with ROS2
7. Setup Rviz2 (Showing different sensor output )
8. Ways to debug projects with Rostopic echo, Rostopic info, RQT_graph
9. Use advance debugging tools like Rqt console, Rqt gui
10 & 11. Implementation of SLAM toolbox or LaMa library for unknown environment.
12. & 13. Implementation of AR-tag detection and getting exact pose from camera.

Note:Following are the system specifications that will be used in the tutorial series.
Ubuntu 20.04, ROS 2 Foxy, Webots R2020b-rev1

This 9th video teaches you the important tools - rqt_gui , rqt console etc.

02:31 rqt_gui
06:19 rqt_console
14:00 Final working project

You can get started with the project using the github link:
https://github.com/cyberbotics/webots_ros2/tree/master/webots_ros2_tutorials
The Master and the Slave node that was used in Tutorial 6 and 8 is continued to be used here. Once the project is built successfully, the project is sourced using the setup file. The robot doesn’t seem to be working as expected and is debugged for issues.
Using rqt_gui:
Rqt_gui virtually subscribes or virtually publishes to any topic.
As seen in the Line Following Robot Project, the robot follows the black line, but here we notice some issues. We see that the robot is not moving, a basic analysis gives us a head start to suspect /cmd_vel. In rqt_gui we can select the /cmd_vel topic from the message and start publishing msg, if the robot moves that means /cmd_vel subscriber is correct there is an issue with the publisher. If the robot still doesn’t move it would mean that the subscriber is/also faulty.
In our case, once we publish the msg in rqt_gui, the robot starts moving. This shows us that the publisher is at fault.
We move on to the implementation of the /cmd_vel publisher and see that in the master node the orders are published at “command_vel” and not “cmd_vel”
Hence we rectify this issue, colcon build and run the project again.

Rqt_console:
This tool is used for seeing and sorting logger messages to debug the system.
After Step 1, we see that the robot is successfully moving but is rotating in a circular fashion.
So there seems to be another issue too. Now it becomes difficult to estimate the culprit. So we update code with logger messages in callbacks of all the topics and start the rqt_console. Here we see messages from different nodes. By this analysis we see that “Left_IR” is not publishing any message.
We check the code and see that there is an issue with publishing Left_IR sensor so we add the publisher in the file and that issue is also solved.

Final working project.
We solved issues using rqt_gui and rqt_console which included an error in /cmd_vel name and left sensor not publishing. After making the necessary changes, we check if the project works fine. Fortunately, we saw that the robot follows the black line as expected.
Hence, this video was a method to teach about advanced debugging tools in a practical scenario to get a better understanding of the tools.
Playlist of the Webots ROS2 tutorial series is available here: https://www.youtube.com/watch?v=jU_FD1_zAqo&list=PLt69C9MnPchkP0ZXZOqmIGRTOch8o9GiQ&index=1&t=242s

Introductory Webots tutorial playlist:
https://www.youtube.com/watch?v=yi4e5...

These videos begin with the basic installation of the simulator and ranges to higher-level applications like object detection, obstacle avoidance, actuator motion, etc.
Facebook link to the Intro Video Artist, Arvind Kumar Bhartia:
https://www.facebook.com/arvindkumar.bhartia.9

Comment if you have any doubts on the above video.
Do Share so that I can continue to make many more videos with the same boost. :)
Happy Coding. :)

Видео Rqt_gui , Rqt_console | Debugging tools | Webots ROS2 Tutorials | [Tutorial 9] канала Soft illusion