FlexBE App

User interface (editor + runtime control) for the FlexBE behavior engine.

Humble

Installation

Clone the following repos into your ROS workspace:

git clone https://github.com/FlexBE/flexbe_behavior_engine.git  # if not already present
git clone https://github.com/FlexBE/flexbe_app.git

Make sure that the branches are consistent (e.g. git checkout humble)

Install any required dependencies.

rosdep update  
rosdep install --from-paths src --ignore-src

Build your workspace:

colcon build

After sourcing the new setup as normally required, you must download the required nwjs binaries before you can run the FlexBE App:

ros2 run flexbe_app nwjs_install

Note: These are installed in the install folder. If the install folder is deleted, then the nwjs binaries will need to be reinstalled with this script.

Workspace

In order to create and prepare a new repository for behavior development, run the following script in your ROS workspace and pass it the name of your project or identifier:

ros2 run flexbe_widget create_repo [your_project_name]

This will initialize a new local git repository with the correct workspace structure which you can then push to a desired remote location. Make sure that you build the workspace afterwards.

Usage

If desired, run the following command to create a shortcut in the application menu:

ros2 run flexbe_app shortcut create
ros2 run flexbe_app shortcut remove  # if you want to remove it

Use the shortcut or the following command to run the FlexBE App alone, i.e., for only developing behaviors, but not executing them:

ros2 run flexbe_app run_app --offline

Omitting the --offline arg will let the App try to connect to ROS. You can manually connect/disconnect the App in the Configuration view.

Use the following launch file to run FlexBE’s operator control station, i.e., everything FlexBE requires on the operator machine for controlling behavior execution:

ros2 launch flexbe_app flexbe_ocs.launch.py
ros2 launch flexbe_onboard behavior_onboard.launch.py  # counterpart expected to run on the robot

Use the following launch file to run both of the above for local behavior execution:

ros2 launch flexbe_app flexbe_full.launch.py

Please note that the way how state and behavior packages are detected has changed and breaks direct compatibility. Follow the instructions below to make the required changes. Behavior packages can also be converted automatically by the new FlexBE App.

State packages

A package is a state package for FlexBE if its package.xml declares the export of flexbe_states:

<package>
...
  <export>
    <flexbe_states />
  </export>
...
</package>

It is then expected to provide Python class definitions as described in Developing Basic States.

Example: flexbe_states

Behavior packages

A behavior package contains the code and manifest files generated by the FlexBE App. Usually, you do not need to modify it manually. Again, a behavior package is identified by an export statement in its package.xml:

<package>
...
  <export>
    <flexbe_behaviors />
  </export>
...
</package>

If no package in the ROS_PACKAGE_PATH contains such an export statement, the FlexBE App will suggest to initialize one of the existing packages as behavior package. Doing so will add the export statement and create the correct structure. If the chosen package already contains behavior manifests, the referenced behaviors can be automatically imported. The old behavior packages and manifests (all manifests outside the manifest folder, e.g., those inside the behaviors folder) can be removed afterwards.

In order to create a completely new behavior package, create an empty ROS package and then use the FlexBE App to initialize it.

A behavior package is expected to provide a manifest folder which contains the manifests for all provided behaviors. The behaviors are located in a Python module named like the package and contained in the src folder.

Publications

Please use the following publications for reference when using FlexBE:

• Philipp Schillinger, Stefan Kohlbrecher, and Oskar von Stryk, “Human-Robot Collaborative High-Level Control with Application to Rescue Robotics”, IEEE International Conference on Robotics and Automation (ICRA), Stockholm, Sweden, May 2016.

• Joshua Zutell, David C. Conner and Philipp Schillinger, “ROS 2-Based Flexible Behavior Engine for Flexible Navigation ,”, IEEE SouthEastCon, April 2022.

Any contribution that you make to this repository will be under the 3-Clause BSD License, as dictated by that license.