Installation
install navigation 2 stack:
sudo apt install ros-humble-navigation2 ros-humble-nav2-bringup ros-humble-turtlebot3*
install tools:
# colcon
sudo apt install python3-colcon-common-extensions
# git
sudo apt install git
# terminator (optional) ctrl+shift+o, ctrl+shift+e
sudo apt install terminator
#vs code (optional)
sudo snap install code --classic
Understand the Nav2 Stack
Global Planner
Nav2 supports various path planning algorithms, such as Dijkstra’s algorithm, A* algorithm, and others, which help the robot find collision-free paths in the environment.
Global Planner will use the entire map to compute the path, it will try to reach the destination as fast as possible with the best possible path. (Use Global Costmap to compute it)
Local Planner / Controller
The controller component is responsible for executing the planned path and controlling the robot’s motion.
Global path will be sent to the controller, which will try to follow this path (high update rate).
Parameters
rqt -> Plugins -> Configuration -> Dynamic Reconfigure
global_costmap
- publish_frequency
- update_frequency
- inflation_radius
- robot_radius
- …
recovery behaviour
Nav2 provides recovery behaviors that the robot can use to handle unexpected situations or failures in navigation.
