Autonomous Control

Note

This section assumes that you have already completed Building the Car, System Configuration, Installing Driver Stack, Manual Control, and Odometry Calibration.

This section goes through how to subscribe to sensor topics, and how to publish drive topic to control the car.

Required Equipment:

  • Fully built F1TENTH vehicle

  • Pit/Host computer

  • Logitech F710 joypad

Difficulty Level: Intermediate

Approximate Time Investment: 1 hour

Sensor Topics

  • /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.

Drive Topic

  • /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.

Bringup and Deadman’s Switch

To enable autonomous control, all you have to do is launch the bring up launch described in testing teleop and LiDAR. Then, publish to the drive topic, and hold the Deadman’s Switch for those messages to pass through. The Deadman’s Switch for Autonomous Control is by default the RB button on the joystick.

Developing your own Node for Autonomous Control

Since we’re using a docker container, there are two options when it comes to where to put your new custom node. In the following section, we’ll go over all the options in detail.

  1. Developing directly in the driver stack container. This is the most straightforward approach since most of the dependencies are already set up for you. When you create a new package alongside f1tenth_system, you’ll need to define your dependencies in package.xml (and CMakeLists.txt if you’re using C++). Then, use rosdep to install your dependencies with the following commands:

cd /f1tenth_ws
rosdep install -i --from-path src --rosdistro foxy -y

This will install the dependencies you declared in package.xml from all the packages in the src directory in your workspace. Then, run colcon build to build your packages. After you’ve added your custom package, you can either create your own launch file to launch your nodes, or add to the bringup launch file we provided to launch your nodes.

2. Create your own docker container. This is the more portable solution when you need to put your code on another car. If you’re an advanced user of Docker, the recommended way to do this is to create your own Dockerfile with ROS 2 included (you can use ROS’s official image). If you need GPU access in your custom Dockerfile, you can use the image we provided (f1tenth/focal-l4t-foxy:f1tenth-stack) as the parent image. The containers (your custom container and the driver stack container) will be put on the same network by default by docker, so communication through ROS 2 should work automatically.