F1TENTH ROS

Some notes on the various topics that you interface with when doing ROS development.

Command I use for first time launch

cd ~/f1tenth_ws/src
sudo rocker --nvidia --x11 --volume .:/sim_ws/src -- f1tenth_gym_ros

For some reason, this command stopped working suddenly… so I have to use the version without gpu. sudo docker-compose up. Then, run the command

docker exec -it f1tenth_gym_ros-sim-1 /bin/bash

To change the sim.yaml,

vim /sim_ws/install/f1tenth_gym_ros/share/f1tenth_gym_ros/config/sim.yaml

Change to

map_path: '/sim_ws/src/particle_filter/maps/e7_floor5_biggest'
map_img_ext: '.pgm'

Then, startup the simulator

source /opt/ros/foxy/setup.bash
source install/local_setup.bash
ros2 launch f1tenth_gym_ros gym_bridge_launch.py

You can run all of your ros2 stuff outside the container, my brain just short circuited.

ros2 run rrt rrt —ros-args -p

Physical Car

Topics Published

On the physical car, the following ROS topics are automatically published:

• /scan: this topic maintains the LaserScan messages published by the LiDAR
• /odom: this topic maintains the Odometry messages published by the VESC
• /sensors/imu/raw: this topic maintains the Imu messages published by the VESC
• /sensors/core: this topic maintains the VescStateStamped messages published by the VESC on telemetry data

To drive the car autonomously, simply publish to the /drive topic and press the deadman’s switch (RB button on joystick):

• /drive: this topic is listened to by the VESC, needs AckermannDriveStamped messages. The speed and steering_angle fields in the drive field of these messages are used to command desired steering and velocity to the car.

Simulation

Difference in Topic Names for Simulation <> Real

I didn’t know that simulation and physical car had different topic names.

The main difference is /odom vs /ego_racecar/odom. This is likely the reason that the simulation code was not working on the real car when you tried running the Pure Pursuit Code.

Also, it’s pretty cool how in simulation, you can have multiple cars.

In simulation, when you want to change the things, you need to

Topics Published

In single agent:

• /scan: The ego agent’s laser scan
• /ego_racecar/odom: The ego agent’s odometry
• /map: The map of the environment

A tf tree is also maintained.

In two agents (In addition to the topics available in the single agent scenario):

• /opp_scan: The opponent agent’s laser scan
• /ego_racecar/opp_odom: The opponent agent’s odometry for the ego agent’s planner
• /opp_racecar/odom: The opponent agents’ odometry
• /opp_racecar/opp_odom: The ego agent’s odometry for the opponent agent’s planner

Topics Subscribed

In single agent:

• /drive: The ego agent’s drive command via AckermannDriveStamped messages
• /initalpose: This is the topic for resetting the ego’s pose via RViz’s 2D Pose Estimate tool. Do NOT publish directly to this topic unless you know what you’re doing.

TODO: kb teleop topics

In two agent (In addition to all topics in the single agent scenario):

• /opp_drive: The opponent agent’s drive command via AckermannDriveStamped messages
• /goal_pose: This is the topic for resetting the opponent agent’s pose via RViz’s 2D Goal Pose tool. Do NOT publish directly to this topic unless you know what you’re doing.