Operation - Additional Software Tools#

This section describes how to use additional software tools for your Duckiebot.

GUI tools#

To open a terminal with access to your Duckiebot’s ROS network, run:

dts gui ![DUCKIEBOT_NAME]

Note

Only a single instance of the start_gui_tools container can exist on your computer at a time. If multiple terminal instances are required, use noVNC.

noVNC#

To open a desktop environment connected to your Duckiebot, run:

dts gui --vnc ![DUCKIEBOT_NAME]

To open a terminal within this desktop environment, click the Terminal desktop icon.

ROS#

Once you have opened a terminal with access to your Duckiebot’s ROS network, you can do the following using that terminal.

See a list of topics#

To see a list of topics, run:

rostopic list

Note

The following topics should be present:

/![DUCKIEBOT_NAME]/camera_node/camera_info
/![DUCKIEBOT_NAME]/camera_node/image/compressed
/rosout
/rosout_agg

See the publishing frequency for a topic#

To see the publishing frequency for a topic, run the following command, where ![TOPIC] is the topic (e.g., /![DUCKIEBOT_NAME]/camera_node/image/compressed):

rostopic hz ![TOPIC]

Note

For a Raspberry Pi 3, you should see a publishing frequency of around 30 Hz for the /![DUCKIEBOT_NAME]/camera_node/image/compressed topic:

average rate: 30.016
    min: 0.026s max: 0.045s std dev: 0.00190s window: 841

To stop rostopic hz ![TOPIC], press Ctrl-C.

See messages being sent to a topic#

To see messages being sent to a topic, run the following command, where ![TOPIC] is the topic (e.g., /![DUCKIEBOT_NAME]/camera_node/image/compressed):

rostopic echo ![TOPIC]

Note

For the /![DUCKIEBOT_NAME]/camera_node/image/compressed topic, you should see a large sequence of numbers being printed to your terminal.

See what your Duckiebot sees#

To see what your Duckiebot sees, run the following command and select the /![DUCKIEBOT_NAME]/camera_node/image/compressed topic from the drop-down menu:

rqt_image_view

Note

If you are using noVNC, you can also click the RQT Image View desktop icon.

../../_images/rqt_image_view.png

Fig. 52 The rqt_image_view window with the /![DUCKIEBOT_NAME]/camera_node/image/compressed topic dropdown menu option shown.#

See a graphical representation of your Duckiebot’s ROS network#

To see a graphical representation of your Duckiebot’s ROS network, run:

rqt_graph

Troubleshooting#

Troubleshooting

SYMPTOM

My ROS commands are not working and I cannot use Tab to autocomplete any ROS commands.

RESOLUTION

Run:

source /code/catkin_ws/devel/setup.bash

Troubleshooting

SYMPTOM

I cannot connect to my Duckiebot’s ROS Master.

RESOLUTION

Run the following command and make sure that the ROS, car-interface and duckiebot-interface containers are running:

dts duckiebot dashboard ![DUCKIEBOT_NAME] --page portainer