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Home Courses Hello (Real) World with ROS – Robot Operating System Course materials Lectures 5.2.2 TF Reference Frames

5.2.2 TF Reference Frames

Course subject(s) Module 5. Robot Vision

In this lecture, we will learn how the TF reference frames are generated and where they are located.

Creation of reference frames:

  • ROS Package: robot_state_publisher
      • joint state information – /joint_states topic
      • robot_description parameter – URDF/XACRO (hrwros.xacro)
  • A fixed reference frame for “world”
  • A joint_state_publisher publishes combines information to the joint state topic
      • source_list combines joint states of the robots
  • Load the URDF on to the parameter server
    <include file="$(find hrwros_support)/launch/load_hrwros.launch"/>

      • Contains robot_description that gets updated with the URDF elements.
  • Use of URDF to define where different objects are.

Location of the reference frame

  • The origin tag
    <origin xyz="-7.8 -1.5 0"/>
  • Objects are defined via links which are connected via joints
  • Frames are defined on joint origins
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Hello (Real) World with ROS - Robot Operating System by TU Delft OpenCourseWare is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Based on a work at https://online-learning.tudelft.nl/courses/hello-real-world-with-ros-robot-operating-systems//.
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