tf2/Tutorials

Many of the tf2 tutorials are available for both C++ and Python. The tutorials are streamlined to complete either the C++ track or the Python track. If you want to learn both C++ and Python, you should run through the tutorials once for C++ and once for Python.

Contents

Workspace Setup
Learning tf2
Debugging tf2
Using sensor messages with tf2
Setting up your robot with tf2
Extending tf2
Migrating from tf1 to tf2

Workspace Setup

If you have not yet created a workspace in which to complete the tutorials, click here for some brief instructions click here for some brief instructions .

Show EOL distros:

Create a file named ~/tutorials.rosinstall with the following content:

- other: { local-name: workspace }

To overlay on the ROS distro you are using:

rosinstall ~/tutorials /opt/ros/$ROS_DISTRO>> ~/tutorials.rosinstall

To use this workspace whenever you open a new terminal setup your ROS environment by typing:

source ~/tutorials/setup.bash

Sourcing this file adds ~/tutorials/workspace to your ROS_PACKAGE_PATH.

Any packages you create in that directory will be found by rospack.

An alternative to source your script file is to add it to your .bashrc, but remember that this will persist in your .bashrc into the future, and you can only have one environment setup. For more on what this is doing see this page

Create a catkin workspace like so:

$ source /opt/ros/$ROS_DISTRO/setup.bash
$ mkdir -p ~/tutorial_ws/src
$ cd ~/tutorial_ws
$ catkin_init_workspace src
$ catkin_make

And now source the setup file from the result-space, so that packages you add to this workspace's src folder will be findable by rospack, and the built binaries by rosrun and roslaunch:

$ source devel/setup.bash

Learning tf2

1. tf2/Tutorials/Introduction to tf2

This tutorial will give you a good idea of what tf2 can do for you. It shows off some of the tf2 power in a multi-robot example using turtlesim. This also introduces using tf2_echo, view_frames, and rviz.

C++

Python

Writing a tf2 static broadcaster (C++)
This tutorial teaches you how to broadcast static coordinate frames to tf2
Writing a tf2 broadcaster (C++)
This tutorial teaches you how to broadcast coordinate frames of a robot to tf2.
Writing a tf2 listener (C++)
This tutorial teaches you how to use tf2 to get access to frame transformations.
Adding a frame (C++)
This tutorial teaches you how to add an extra fixed frame to tf2.
Learning about tf2 and time (C++)
This tutorial teaches you to wait for a transform to be available on the tf2 tree when using the lookupTransform() function.
Time travel with tf2 (C++)
This tutorial teaches you about advanced time travel features of tf2

Writing a tf2 static broadcaster (Python)
This tutorial teaches you how to broadcast static coordinate frames to tf2
Writing a tf2 broadcaster (Python)
This tutorial teaches you how to broadcast the state of a robot to tf2.
Writing a tf2 listener (Python)
This tutorial teaches you how to use tf2 to get access to frame transformations.
Adding a frame (Python)
This tutorial teaches you how to add an extra fixed frame to tf2.
Learning about tf2 and time (Python)
This tutorial teaches you to use the timeout in lookup_transform function to wait for a transform to be available on the tf2 tree.
Time travel with tf2 (Python)
This tutorial teaches you about advanced time travel features of tf2

Debugging tf2

Using sensor messages with tf2

Using Stamped datatypes with tf2_ros::MessageFilter

Setting up your robot with tf2

Setting up your robot using tf
This tutorial provides a guide to set up your robot to start using tf.
Using the robot state publisher on your own robot
This tutorial explains how you can publish the state of your robot to tf, using the robot state publisher.
Using urdf with robot_state_publisher
This tutorial gives a full example of a robot model with URDF that uses robot_state_publisher. First, we create the URDF model with all the necessary parts. Then we write a node which publishes the JointState and transforms. Finally, we run all the parts together.

Extending tf2

Transforming your own datatypes