Add support for non-ros py-trees-viewer

[fred-labs]

Currently there are two modes of viewing the current state of a behavior tree.

• in terminal, using live_tree argument
• graphical visualization using ROS2 snapshot, either within RViz2 (using the scenario_execution_rviz plugin) or with the py_trees_ros_viewer.

With py_trees_js it is possible to visualize the behavior tree without the need for ROS2, using a web-socket.

Extend scenario-execution to support a py-trees-js-based visualization.

Required Skills

• Javascript
• network communication
• optional: python, C++, Qt

Challenges

While the visualization parts are already available, the main challenge is to send the required data from scenario-execution to the visualization. As an extension the visualization might also be provided by an Qt/Rviz2 plugin.