CLEARPATH TurtleBot 4 Lite, Руководство пользователя

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Creating your first node (C++)
This tutorial will go through the steps of creating a ROS2 package and writing a ROS2 node in
C++. For a Python example, click
here . These steps are similar to the ROS2 Tutorial , but focus
on interacting with the TurtleBot 4. For source code, click here .
Note
You can follow this tutorial on either the Raspberry Pi of your TurtleBot 4, or your PC.
Create a workspace
If you do not already have a workspace, open a terminal and create one in the directory of your
choice:
mkdir ~/turtlebot4_ws/src -p
Create a package and node
You will need to create a ROS2 package to hold your files. For this tutorial, we will create a
package called
turtlebot4_cpp_tutorials with a node called turtlebot4_first_cpp_node .
source /opt/ros/galactic/setup.bash
cd ~/turtlebot4_ws/src
ros2 pkg create --build-type ament_cmake --node-name turtlebot4_first_cpp_node
turtlebot4_cpp_tutorials
This will create a turtlebot4_cpp_tutorials folder and populate it with a basic "Hello World" node,
as well as the CMakeLists.txt and package.xml files required for a ROS2 C++ package.
Write your node
The next step is to start coding. For this tutorial, our goal will be to use the Create® 3 interface
button 1 to change the colour of the Create® 3 lightring. Open up the "Hello World"
.cpp file
located at ~/turtlebot4_ws/src/turtlebot4_cpp_tutorials/src/turtlebot4_first_cpp_node.cpp in your
favourite text editor.