Compatibility issues with ROS1

[DarkJoker9817]

Hello everyone, I have to evolve an FSM behavior model into BT on an already existent architecture that uses ROS1 for interaction and navigation on Pepper robot. Now I have designed the behavior tree and I have to use a lot of Sequence node without memory to ensure reactivity of the robot, but these are are not supported in py_trees 0.7 which is the version that is automatically installed when I install ros-noetic-py-trees-ros. Is py-trees-ros mandatory in my case? Or I can use only py_trees 2.2 for having Sequence node without memory and other stuffs?

[stonier]

YMMV, but py_trees is almost pure python, so problems would be limited

• Python compatibility - noetic is py3 I believe, so a node dependening on py_trees 2.2 should be possible
• package.xml - unsure if this will be compatible, worst case, you'll have to patch it with a ros1 equivalent or bring in the pypi package as a dependency and treat it as a pure python package
• Behaviours - you may want to recreate some of the py_trees_ros behaviours in a library of your own
• Tools - the biggest miss will probably be the tooling, i.e. blackboard/tree watcher, ros viewer, hard to recreate that