Additional Software Tools#

This chapter describes additional software tools.

What you will need

Completed Duckiebot Dashboard.

What you will get

Knowledge on additional software tools.

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#

Note

The following requires a terminal with access to your Duckiebot’s ROS network.

How to 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

How to 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.

How to 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.

How to 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_view1.png

Fig. 48 The rqt_image_view window with the /DUCKIEBOT_NAME/camera_node/image/compressed topic dropdown menu option shown.#

How to 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