README.md

Norlab controllers ROS

Description

Norlab controllers ROS is a set of ROS packages enabling path following for uncrewed ground vehicles (UGVs). This repository also includes the norlab_controllers python library providing an implementation of various popular controllers. The goal of this repository is to offer a lean and modular solution for UGV path following.

For installation, you need to clone the repository in your ROS 2 workspace, initialize its submodules and install the library:

cd <PATH_TO_YOUR_ROS2_WORKSPACE>/src/
git clone [email protected]:norlab-ulaval/norlab_controllers_ros.git
git submodule init
git submodule update
cd norlab_controllers_ros/norlab_controllers/
./install.sh
cd <PATH_TO_YOUR_ROS2_WORKSPACE>/src/
colcon build --symlink-install
source install/local_setup.bash

Usage

The main package, norlab_controllers_wrapper acts as a ROS2 action server. The server recieves target paths as actions sent by the client, these custom actions are defined in the norlab_controllers_msgs package. Refer to our WILN package for a functional implementation of a action client.

Launching the nodes

A set of launch files are provided in the norlab_controllers_wrapper package. These launch files allow to run the path-following nodes:

ros2 launch norlab_controllers_wrapper warthog_wheels_mpc_launch.xml

For quick bootstrapping, the different services of WILN can be used to perform teach-and-repeat operation.

Tuning the controller's parameters

Controller parameters are defined and can be modified in the params folder. Please note that the norlab_controllers_inspector could then be used to visualize and quantify the controller performance. Controller parameters files are in the YAML format. For faster tuning, you can build your ROS2 workspace with symbolic links to prevent the requirement to rebuild the workspace anytime you change a parameter or change a script.

colcon build --symlink-install