[Turtlebot 4 Lite] Launhing the OAK-D; Topics Missing

I would like to use the OAK-D camera of my Turtlebot4 Lite:
In the terminal of the robot I launched:

ros2 launch turtlebot4_bringup oakd_example.launch.py

I obtain this error:

[INFO] [launch]: All log files can be found below /home/ubuntu/.ros/log/2023-03-02-21-41-24-570942-ubuntu-1888
[INFO] [launch]: Default logging verbosity is set to INFO
[INFO] [rgb_stereo_node-1]: process started with pid [1889]
[rgb_stereo_node-1] terminate called after throwing an instance of ‘std::runtime_error’
[rgb_stereo_node-1] what(): Failed to connect to device, error message: X_LINK_DEVICE_ALREADY_IN_USE

[ERROR] [rgb_stereo_node-1]: process has died [pid 1889, exit code -6, cmd ‘/opt/ros/humble/lib/depthai_examples/rgb_stereo_node --ros-args --params-file /tmp/launch_params_uam37w4i --params-file /tmp/launch_params_dxi1p_t7 --params-file /tmp/launch_params_twkkxody --params-file /tmp/launch_params_iq_h2wim --params-file /tmp/launch_params_fmfglmk9 --params-file /tmp/launch_params_2izczv3v --params-file /tmp/launch_params_pt43k937 --params-file /tmp/launch_params_90lemoyw --params-file /tmp/launch_params_x1syn1vr --params-file /tmp/launch_params_34464z7v --params-file /tmp/launch_params_q5dj19n4 --params-file /tmp/launch_params_tcuh40y4 --params-file /tmp/launch_params_5brddpr_ --params-file /tmp/launch_params_4w1wo9rg’].

How can I solve it?


Dear @Raoui,

The turtlebot4 on startup launches all lidars and depth cameras, so you should not run it as it is already running.

Dear @Sohail
I can’t find the topics of the camera and the LIDAR in my PC.
I reinstalled the Ubuntu 22.04, but the problem remains. How can I resolve this problem?


In turtlebot4-setup → set up Bash:
CYCLONEDDS_URI [/etc/turtlebot4/cyclonedds_rpi.xml]
FASTRTPS_DEFAULT_PROFILES_FILE [/etc/turtlebot4/fastdds_discovery_super_client.xml]

As well as this tutorial
Discovery Server · User Manual

Set up the discovery server on my PC and enabled 2.4GHz for my router.

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