AWS DeepRacer Follow the Leader (FTL) navigation package

Overview

The AWS DeepRacer Follow the Leader (FTL) navigation ROS package creates the ftl_navigation_node, which decides the action and controller messages to send out using the normalized detection error (delta) received from the object_detection_node. For more information, see the AWS DeepRacer Follow the Leader (FTL) sample project.

License

The source code is released under Apache 2.0.

Installation

Follow these steps to install the AWS DeepRacer Follow the Leader (FTL) navigation package.

Prerequisites

The AWS DeepRacer device comes with all the prerequisite packages and libraries installed to run the FTL sample project. For more information about the preinstalled set of packages and libraries on the AWS DeepRacer, and about installing the required build systems, see Getting started.

The ftl_navigation_pkg specifically depends on the following ROS 2 packages as build and run dependencies:

1. deepracer_interfaces_pkg: This package contains the custom message and service type definitions used across the AWS DeepRacer core application, modified to support the FTL sample project.

Downloading and building

Open up a terminal on the AWS DeepRacer device and run the following commands as the root user.

1. Switch to the root user before you source the ROS 2 installation:

    sudo su
   

2. Source the ROS 2 Foxy setup bash script:

    source /opt/ros/foxy/setup.bash 
   

3. Set the environment variables required to run Intel OpenVino scripts:

    source /opt/intel/openvino_2021/bin/setupvars.sh
   

4. Create a workspace directory for the package:

    mkdir -p ~/deepracer_ws
    cd ~/deepracer_ws
   

5. Clone the entire FTL sample project on the AWS DeepRacer device:

    git clone https://github.com/aws-deepracer/aws-deepracer-follow-the-leader-sample-project.git
    cd ~/deepracer_ws/aws-deepracer-follow-the-leader-sample-project/deepracer_follow_the_leader_ws/
   

6. Fetch the unreleased dependencies:

    cd ~/deepracer_ws/aws-deepracer-follow-the-leader-sample-project/deepracer_follow_the_leader_ws/
    rosws update
   

7. Resolve the dependencies:

    cd ~/deepracer_ws/aws-deepracer-follow-the-leader-sample-project/deepracer_follow_the_leader_ws/ && apt-get update
    rosdep install -i --from-path . --rosdistro foxy -y
   

8. Build the ftl_navigation_pkg and deepracer_interfaces_pkg:

    cd ~/deepracer_ws/aws-deepracer-follow-the-leader-sample-project/deepracer_follow_the_leader_ws/ && colcon build --packages-select ftl_navigation_pkg deepracer_interfaces_pkg
   

Using the ftl_navigation_mode

Although the ftl_navigation_node is built to work with the FTL sample project, you can run it independently for development, testing, and debugging purposes.

Running the node

To launch the built ftl_navigation_node as the root user on the AWS DeepRacer device, open another terminal on the AWS DeepRacer device and run the following commands as the root user.

1. Switch to the root user before you source the RO S2 installation:

    sudo su
   

2. Navigate to the FTL workspace:

    cd ~/deepracer_ws/aws-deepracer-follow-the-leader-sample-project/deepracer_follow_the_leader_ws/
   

3. Source the ROS 2 Foxy setup bash script:

    source /opt/ros/foxy/setup.bash 
   

4. Source the setup script for the installed packages:

    source ~/deepracer_ws/aws-deepracer-follow-the-leader-sample-project/deepracer_follow_the_leader_ws/install/setup.bash 
   

5. Launch the ftl_navigation_node using the launch script:

    ros2 launch ftl_navigation_pkg ftl_navigation_pkg_launch.py
   

Launch files

The ftl_navigation_pkg_launch.py launch file included in this package gives an example of how to launch the ftl_navigation_node.

    from launch import LaunchDescription
    from launch_ros.actions import Node

    def generate_launch_description():
        return LaunchDescription([
            Node(
                package='ftl_navigation_pkg',
                namespace='ftl_navigation_pkg',
                executable='ftl_navigation_node',
                name='ftl_navigation_node'
            )
        ])

Node details

ftl_navigation

Subscribed topics

Published topics

Services

Resources

• Getting started with AWS DeepRacer OpenSource
• Getting started with the Follow the Leader (FTL) sample project