Note: This tutorial assumes that you have completed the previous tutorials: Spawn simple URDF object in simulation.
(!) Please ask about problems and questions regarding this tutorial on answers.ros.org. Don't forget to include in your question the link to this page, the versions of your OS & ROS, and also add appropriate tags.

Attaching a ROS Ground Truth Pose Broadcaster to Objects in Simulation

Description: Attaching a ROS ground truth pose broadcaster to objects in simulation

Tutorial Level:

Contents

  1. Attaching a Ground Truth Plugin

Users are highly discouraged from using the documentation and tutorials for Gazebo on this page. Gazebo is now a stand alone project at gazebosim.org. See documentation there, thanks!

Attaching a Ground Truth Plugin

  1. Update the URDF from this tutorial by adding a Gazebo extension for ros_p3d plugin: 

    <?xml version="1.0"?>
<robot xmlns:controller="http://playerstage.sourceforge.net/gazebo/xmlschema/#controller" name="simple_box">
  <gazebo>
    <controller:ros_p3d name="my_box_controller" plugin="libros_p3d.so">
      <alwaysOn>true</alwaysOn>
      <updateRate>100.0</updateRate>
      <bodyName>my_box</bodyName>
      <topicName>my_box_pose_ground_truth</topicName>
      <gaussianNoise>0.0</gaussianNoise>
      <frameName>my_box</frameName>
      <interface:position name="my_box_p3d_position_iface" />
    </controller:ros_p3d>
  </gazebo>

  <joint name="my_box_joint" type="revolute" >
    <!-- axis is in the parent link frame coordintates -->
    <axis xyz="0 1 0" />
    <parent link="world" />
    <child link="my_box" />
    <!-- initial pose of my_box joint/link in the parent frame coordiantes -->
    <origin xyz="0 0 2" rpy="0 0 0" />
  </joint>
  <link name="my_box">
    <inertial>
      <mass value="1.0" />
      <!-- center of mass (com) is defined w.r.t. link local coordinate system -->
      <origin xyz="1 0 0" /> 
      <inertia  ixx="1.0" ixy="0.0"  ixz="0.0"  iyy="100.0"  iyz="0.0"  izz="1.0" />
    </inertial>
    <visual>
      <!-- visual origin is defined w.r.t. link local coordinate system -->
      <origin xyz="1 0 0" rpy="0 0 0" />
      <geometry name="my_box_visual_geom">
        <box size="0.05 0.05 0.10" />
      </geometry>
    </visual>
    <collision>
      <!-- collision origin is defined w.r.t. link local coordinate system -->
      <origin xyz="1 0 0" rpy="0 0 0 " />
      <geometry name="my_box_collision_geom">
        <box size="0.05 0.05 0.10" />
      </geometry>
    </collision>
  </link>
  <gazebo reference="my_box">
    <material>Gazebo/Blue</material>
    <turnGravityOff>false</turnGravityOff>
  </gazebo>
</robot>

The additional Gazebo extension block below: 

  <gazebo>
    <controller:ros_p3d name="my_box_controller" plugin="libros_p3d.so">
      <alwaysOn>true</alwaysOn>
      <updateRate>100.0</updateRate>
      <bodyName>my_box</bodyName>
      <topicName>my_box_pose_ground_truth</topicName>
      <gaussianNoise>0.0</gaussianNoise>
      <frameName>my_box</frameName>
      <interface:position name="my_box_p3d_position_iface" />
    </controller:ros_p3d>
  </gazebo>

instantiates a ros_p3d plugin that broadcasts a geometry_msgs/Pose message over ROS topic my_box_pose_ground_truth. To see pose information, run 

rostopic echo my_box_pose_ground_truth

after simulation has started.

Wiki: pr2_gazebo_plugins/Tutorials/Creating a ROS Ground Truth Pose Broadcaster (last edited 2013-05-24 01:14:27 by davetcoleman)

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