Use a launch file to launch multiple cameras at the same time in ros

1. First download the ros driver source code of usb-cam (if you can already drive a single camera, you can ignore step 1 and go to step 2 directly)

Code link: https://github.com/ros-drivers/usb_cam https://github.com/ros-drivers/usb_cam

And copy the code to your ros workspace. If there is no ros workspace, you need to create it first. For how to create a ros workspace, you can refer to my other blog:

 https://blog.csdn.net/qq_49959714/article/details/127028396?spm=1001.2014.3001.5502

 Enter the workspace and execute catkin_make to compile it.

Execute the following command to start a single camera:

source devel/setup.bash
roslaunch usb_cam usb_cam-test.launch

2. Start multiple cameras at the same time

Here you need to configure the corresponding files

1) Write sublaunch

For example, if I have 7 cameras here, I need to write 7 sub-launches.

Directly copy the original usb_cam-test.launch and modify it

The specific modifications are as follows:

 2) Write the total launch file

Add sub-launch

 3) Write nodes nodes

Here we also need to start several cameras and write several nodes.

 Directly copy usb_cam_node.cpp and modify it. The specific modification content is as follows in the red box:

4) Modify the CMakeLists.txt configuration file

What are the specific modifications:

 As many nodes as there are, add several add_executable and install

 At this point, the file configuration has been completed.

 5) Enter the workspace directory and recompile

catkin_make

 

6) Execute roscore in a new terminal

 

 7) Start launch

roslaunch usb_cam usb_cam-test-total.launch

 

 Here you can see the 7 cameras we started at the same time

 8) Visualize using ros

rosrun rviz rviz

 Open RVIZ to subscribe to the topic of 7 cameras