F1tenth workspace

Clone

git [email protected]:wette/wette_racecar_ws.git
cd wette_racecar_ws
git submodule init
git submodule update

Build with colcon

colcon build

Create a Map using google cartographer (works ok, but slam_toolbox works better)

Map From Scratch

To create a new map from scratch, we need to run cartographer in map-creation-mode, and let the vehicle drive slowly through the racetrack using gap_follow.

ros2 launch vehicle_control vehicle_control_launch.py
ros2 launch cartographer_ros cartographer_new_map.launch.py

once, the map is good, it can be saved using commands

ros2 service call /finish_trajectory cartographer_ros_msgs/srv/FinishTrajectory "{trajectory_id: '0'}"
ros2 service call /write_state cartographer_ros_msgs/srv/WriteState "{filename: '/root/cartographer_ws/map.pbstream'}"

which creates the file /root/cartographer_ws/map.pbstream

from map.pbstream, a map.pgm and map.yaml can be created using

ros2 run cartographer_ros cartographer_pbstream_to_ros_map -pbstream_filename=/root/cartographer_ws/map.pbstream -map_filestem=map

The files /root/cartographer_ws/map.pgm and map.yaml should be created.

Fixed Map

To use an existing map, cartographer needs to be run in localization-only mode:

ros2 launch vehicle_control vehicle_control_launch.py
ros2 launch cartographer_ros cartographer_existing_map.launch.py map_filename:=/root/cartographer_ws/map.pbstream

Create a Map using slam_toolbox (works quite good)

Start Slam Toolbox with command

ros2 launch slam_toolbox online_async_launch.py slam_params_file:=/root/wette_racecar_ws/mapping_localization/mapper_params_online_async.yaml

Open rviz and add the SlamToobox Panel (Panels --> Add new panels). You can find a "save to file" button there.

Localize in that map using slam_toolbox (has its own problems due to non-fixed map clashing with a fixed raceline)

ros2 launch slam_toolbox online_async_launch.py slam_params_file:=/root/wette_racecar_ws/mapping_localization/localization_params_online_async.yaml

Localize in that map using AMCL Montecarlo Localization (from the nav2 stack - works quite good)

ros2 launch mapping_localization/localization_launch_amcl.py params_file:=mapping_localization/nav2_params.yaml map:=MindenCitySpeedway0408.yaml

If the map does not show up in rviz2, set Map->Topic->"Durability Policy" to "Transient Local" in the left rviz control pane.

Helpful resources

• https://guni91.wordpress.com/2020/12/05/cartographer-ros2-installation/
• https://google-cartographer-ros.readthedocs.io/en/latest/algo_walkthrough.html