bt_tools

There are 3 tools to view behavior trees:

btlib

A Library to parse behavior trees.

How to generate fbl files

To analyze past runs of a behavior tree, you need to enable the logging to fbl files. This is a feature of the BehaviorTree.CPP library but for example navigation2 does currently not support it. You can enable the support like this: https://github.com/ct2034/navigation2/commit/b019fbc49d72dd34a45128bb20d1114e9b8c2b24

bt_live

Look at the behavior tree at runtime

Usage

The tool currently requires an fbl log file, because it contains the tree definition. But it will then visualize the tree at runtime based on the messages published unter /behavior_tree_log.

ros2 run bt_live bt_live --ros-args -p fbl_file:=<path_to_fbl_log>

Then open a browser at http://localhost:8000 to see the visualization. It should look a little something like this:

bt_view

Tools to visualize and analyze past behavior tree runs.

Visualizing a fbl log

ros2 run bt_view bt_view --bt_log_fbl_fnames <path_to_fbl_log>

The tool will output images about

• the count of calls with the suffix _count.png and
• the return states with the suffix _states.png to the same folder that the fbl log is in.

For example, the _states.png file will look like this:

Calculate coverage

ros2 run bt_view bt_view --bt_log_fbl_fnames <path_to_fbl_log> --coverage-threshold <threshold>

The tool will count the percentage of nodes that have been executed in the giben fbl file(s). Iff above the threshold, it will return 0.

Contributing

Contribution Guidelines

See Contributing.

Feedback

Feedback is highly appreciated. Please open issues on new ideas, bugs, etc. here at bt_tools/issues or reach out to the maintainers.

About

Presentations

• ROSCon 2023: Supporting Robotic Deliberation: The Deliberation Working Group and Tools for Behavior Trees
  • Video
  • Slides

Maintainers

• Christian Henkel

Contributors

... are welcome at any time and will be listed here. We thank Robert Schirmer for the valuable input and discussions about the design of bt_tools.

3rd Party Licenses

Currently, bt_tools does not come with any 3rd-party components/modules. Note that bt_tools highly depends on ROS 2, which largely comes under the permissive licenses Apache 2.0 and 3-clause BSD.

License

bt_tools comes under the Apache-2.0 license, see LICENSE.