### 1. Install the ROS package [agni-tf-tools](http://wiki.ros.org/agni_tf_tools)
`sudo apt install ros-melodic-agni-tf-tools`
### 2. Source your ROS environment, and start `roscore` as well as [`rviz`](http://wiki.ros.org/rviz)
```bash
source /opt/ros/melodic/setup.bash
roscore &
rosrun rviz rviz
```
### 3. Add new displays, namely `TF` and `Static Transform Publisher`
[[rviz-frames.png]]
Using several transform publishers, build up a transformation tree like this:
```
world
↳ T1 → R1
↳ R2 → T2
```
where translations (T) are 0.5m along the y-axis, and rotations (R) are -90° about the z-axis (see image).
### 4. Using the TF display, readout the following relative transforms
* world → R1
* R1 → world
* R1 → T2
To this end, define rviz's `fixed frame` to the parent frame and readout the corresponding transformation from the child frame in TF display's frames list.
