roslaunch uvc_camera camera_node.launch

The command `roslaunch uvc_camera camera_node.launch` launches the uvc_camera package in ROS, which provides a node to stream images from USB Video Class (UVC) compatible devices, such as webcams.

When you run this command, ROS will start the `camera_node` with the configurations specified in the `camera_node.launch` file. This launch file typically includes parameters such as camera resolution, frame rate, image topic name, and camera device settings.

Make sure that you have the `uvc_camera` package installed in your ROS workspace before running this command. If it is not installed, you can use the following command to install it:

sudo apt-get install ros-<distro>-uvc-camera

Replace `<distro>` with your ROS distribution (e.g., melodic, noetic).

Once the package is installed, navigate to your ROS workspace and run the `roslaunch` command to start streaming images from your camera. The image topic should be published, and you can use tools like `rostopic list` or `rqt_image_view` to verify the image data being received.