ros2_help

A repository to take notes of tutorials and references

observability

• https://docs.ros.org/en/jazzy/Tutorials/Advanced/ROS2-Tracing-Trace-and-Analyze.html
• https://fast-dds-monitor.readthedocs.io/en/latest/rst/formalia/titlepage.html

rqt graph

plot a nodes graph

ros2 run rqt_graph rqt_graph

turtlebot3 sim

env : windows 11, WSL ubuntu 22.04, ros2 humble

youtube video https://www.youtube.com/watch?v=idQb2pB-h2Q&t=1186s

official doc https://emanual.robotis.com/docs/en/platform/turtlebot3/simulation/#gazebo-simulation

installed : ros-humble-gazebo-*, ros-humble-cartographer, ros-humble-cartographer-ros, ros-humble-navigation2, ros-humble-nav2-bringup

note source /opt/ros/humble/setup.bash throws the error [ERROR] [gzclient-2]: process has died [pid 4048, exit code -6, cmd 'gzclient --gui-client-plugin=libgazebo_ros_eol_gui.so'] but gazebo-11 runs fine

added in .bashrc

export TURTLEBOT3_MODEL=waffle
export ROS_DOMAIN_ID=30 #TURTLEBOT3

source /opt/ros/humble/setup.bash
source /usr/share/gazebo-11/setup.sh

launch

• ros2 launch turtlebot3_gazebo turtlebot3_world.launch.py
• ros2 run turtlebot3_teleop teleop_keyboard
• ros2 launch turtlebot3_cartographer cartographer.launch.py use_sim_time:=True

save the map

• ros2 run nav2_map_server map_saver_cli -f maps/my_map

map_saver_cli produces pgm only, can be converted with imagemagick-6.q16 convert my_map.pgm my_map.png

now publish the map on a topic with the map server

ros2 run nav2_map_server map_server --ros-args -p yaml_filename:=my_map.yaml

to fix missing tf publish a dummy one : ros2 run tf2_ros static_transform_publisher 0 0 0 0 0 0 map base_link

alternative method did not work

• fix warn in rviz "Global Status : Warn, Fixed Frame : No tf data. Actual error: Frame [map] does not exist" rmw has better discovery implementation that does not miss tf
• install ros-humble-rmw-cyclonedds-cpp
• export RMW_IMPLEMENTATION=rmw_cyclonedds_cpp
• in /opt/ros/humble/share/turtlebot3_navigation2/params/waffle.yaml make sure robot_model_type: "nav2_amcl::DifferentialMotionModel"

now navigate using the map

• ros2 launch turtlebot3_navigation2 navigation2.launch.py use_sim_time:=True map:=~/turtlebot3_test_map/my_map.yaml