RVIZ

Visualization is a very important concept in robot simulation. In order to visualize the various sensor inputs like LIDAR, Camera etc. we will be using RVIZ 2 a software for visualizing the ROS2 topics.

RVIZ 2 requires setup and configurations that might be overwhelming at this stage so to help out we will be using a few templates.

We move to the root of our package and then run the code below to download the templates.

cd ~/test_ws/src/package-name/

# Example
cd ~/test_ws/src/test_package/

svn export https://github.com/shantanuparabumd/ENPM-662-Introduction-to-Robot-Modelling.git/trunk/templates/rviz

svn export https://github.com/shantanuparabumd/ENPM-662-Introduction-to-Robot-Modelling.git/trunk/templates/template2/launch

So that the robot can move in the RVIZ environment we add a dummy_link to our robot. This is simply done by adding a link and a joint to robot_name.urdf.xacro file as follows.

# Add this before base link
<link name="dummy_link"></link>

# Add this after base link
<joint name="dummy_joint" type="fixed">
    <origin rpy="0 0 0" xyz="0 0 0" />
    <parent link="dummy_link"/>
    <child link="base_link"/>
</joint>

File Description:

  • The gazebo.launch.py will launch the Gazebo environment and will load the controllers.

  • The display.launch.py will launch RVIZ 2 along with the neccessary setup for the Robot Visualization.

  • The debug.launch.py will launch both Gazebo and RVIZ 2 together.

Use any of the above launch files as required.

Once RVIZ is launched Add the robot model to the tree.

If the robot is not visible add the topic /robot_description to the Description Topic argument.

Robot Description Topic

Select dummy_link in the Fixed Frame argument.

Robot Description Topic