Gazebo Setup

• I faced the exact same issue while simulating a custom stereo camera in Gazebo.
  This happens if you don't set the hackBaseline parameter.

• Following is the Gazebo plugin I had used:

  <!-- SENSOR PLUGIN -->
  
  <gazebo reference="left_stereo_camera">
  
      <sensor type="multicamera" name="stereocamera">
          <always_on>true</always_on>
          <update_rate>10</update_rate>
          <camera name="left">
              <pose>0 0 0 0 0 0</pose>
              <horizontal_fov>${radians(front_camera_horizontal_fov)}</horizontal_fov>
              <image>
                  <width>640</width>
                  <height>480</height>
                  <format>RGB_INT8</format>
              </image>
              <clip>
                  <near>0.1</near>
                  <far>100</far>
              </clip>
          </camera>
          <camera name="right">
              <pose>0 -${front_camera_baseline} 0 0 0 0</pose>
              <horizontal_fov>${radians(front_camera_horizontal_fov)}</horizontal_fov>
              <image>
                  <width>640</width>
                  <height>480</height>
                  <format>RGB_INT8</format>
              </image>
              <clip>
                  <near>0.1</near>
                  <far>100</far>
              </clip>
          </camera>        
          <plugin name="stereo_camera_controller" filename="libgazebo_ros_multicamera.so">
              <robotNamespace>/</robotNamespace>
              <cameraName>stereocamera</cameraName>
              <alwaysOn>true</alwaysOn>
              <updateRate>10</updateRate>
              <imageTopicName>image_raw</imageTopicName>
              <cameraInfoTopicName>camera_info</cameraInfoTopicName>
              <frameName>stereo_optical</frameName>
              <hackBaseline>${front_camera_baseline}</hackBaseline>
              <distortion_k1>0.0</distortion_k1>
              <distortion_k2>0.0</distortion_k2>
              <distortion_k3>0.0</distortion_k3>
              <distortion_t1>0.0</distortion_t1>
              <distortion_t2>0.0</distortion_t2>
          </plugin>
      </sensor>
  </gazebo>
  

• If hackBaseline is set to 0.00:
  
  Here you can see the dot in RViz at the centre of the optical frame.

• If hackBaseline is set to 0.06:

References

• [Test Stereo Camera in ROS](https://youtu.be/-lzo1LJ8fvA?t=273)
• [Stereovision in ROS](https://www.youtube.com/watch?v=uXwTAg__2oA)
• [ROS Robotics Projects](https://g.co/kgs/mUaf48)

Note: Please let me know if this solution doesn't work out for you. If in case it does, feel free to upvote my answer.

Comments

Hello, I've got exactly the same issue.
I've set the baseline correctly but I still have only 1point in rviz.
Do you have any other hint ?

Asked by Acwok on 2022-05-04 10:55:30 UTC

Have you spaced the stereo cameras according to your baseline requirement?

Asked by LSD on 2022-05-05 15:33:31 UTC

Hi @LSD, thank you for your quick reply. I finally found the issue. It seems that with the ros2 version of gazebo_ros_pkg the tags <hackBaseline> and <frameName> have been renamed respectively <hack_baseline> and <frame_name> see the code here https://github.com/ros-simulation/gazebo_ros_pkgs/blob/foxy/gazebo_ros/src/utils.cpp#L55

As the <frameName> tag wasn't read/recognized, the only point I had in rviz wasn't placed in my camera_link_optical frame but in the highest parent link of my URDF, that is to say base_footprint. After renaming the tag to <frame_name>, this point was placed at the origin of the camera_link_optical frame. Then I renamed the <hackBaseline> tag and all the points appeared.

The Gazebo documentation really sucks...
They even refer to a libgazebo_ros_multicamera.so for multicameras which doen't exist anymore, it has been included in libgazebo_ros_camera.so.

Asked by Acwok on 2022-05-06 03:11:23 UTC

I'm glad that you have found the solution!

There is a dedicated Wiki to the syntactical changes from ROS1 to ROS2 here.

Since you have faced issues regarding the migration of the camera plugin, I suggest going through the ROS2 Migration changes for the Camera plugin.

Asked by LSD on 2022-05-06 03:33:21 UTC