Steps to run the demo in RViz

Introduction to RViz 2:

RViz 2 is a powerful 3D visualization tool provided by the Robot Operating System (ROS) 2 ecosystem. It serves as an essential component for roboticists, engineers, and researchers to visualize and interact with robot models, sensor data, and other important information in a simulated or real-world environment. RViz 2 offers a user-friendly interface with a wide range of features tailored to support the development, debugging, and testing of robotic systems.Here , along we can visualize the URDF of manipulator on Rviz using command line as well as GUI to give input.

If you have not installed the joint_state_publishers and ros_control for ros-noetic, follow the commands given here

• Remember : Whenever you are using ros commands in another terminal , make sure you source the ros commands:

source install/setup.bash

• Run the launch file

  ros2 launch simulation_rviz display.launch 

• If you come across this error
  Could not find the GUI, install the ‘joint_state_publisher_gui’ package
• Install using
  sudo apt install ros--joint-state-publisher-gui
• Install all the packages required in the same way if needed.

• Once you are done with the visualisation with gui , Ctrl+ c to stop this .

• For command line input

ros2 launch simulation_rviz mario_rviz.launch    

• To give input angles from command line

ros2 run simulation_rviz scripts/rviz.py

*you can use your this command to view the topics actively published . This will show if the values are published to the toppic we want to.

ros2 topic list

*To observe the published data in another terminal

ros2 topic echo

Then initially set all values to zero , to get the default position of the manipulator .
After this you can now check for different values.

As you give the input in the terminal , you can observe how the manipulator moved according to your input values of angles between links.