Author: automaticaddison

To create a package in ROS, you use the catkin_create_pkg command followed by your desired name for the package and then a list of any packages that your package depends on.

Here is the syntax:

catkin_create_pkg <package_name> [depend1] [depend2] [depend3]

For example, let’s create a new package named noetic_basics_part_1 that depends on two packages, std_msgs (a package for handling common data types like integers, strings, and arrays) and roscpp (the standard C++ package for ROS).

In a new terminal window, move to the src (source) folder of your workspace.

cd ~/catkin_ws/src

Now create the package.

catkin_create_pkg noetic_basics_part_1 std_msgs roscpp

If you go inside the package, you’ll see we have all the basic files of a ROS package.

• CMakeLists.txt (contains the commands to build the ROS source code inside the noetic_basics_part_1 package)
• include (where the package header files are located)
• package.xml (contains descriptive information about the package)
• src (the folder that will contain your C++ source code…note that if you write Python code, you’ll want to create another folder inside the package named scripts).

Let’s say we want to move to a specific directory. To do that, we use the roscd command, where cd means “change directory.”

For example, to go to the directory of the turtlesim package, we use this command:

roscd turtlesim

We can verify that we are in fact inside the turtlesim package, by typing this command:

pwd

pwd literally means “print working directory.”

Click on this link at the ROS website to get a list of all ROS packages that are publicly available.