ros-navigation · mini-1235 · Feb 17, 2025
diff --git a/configuration/packages/configuring-bt-navigator.rst b/configuration/packages/configuring-bt-navigator.rst
@@ -11,7 +11,7 @@ The BT Navigator (Behavior Tree Navigator) module implements the NavigateToPose,
 It is a Behavior Tree-based implementation of navigation that is intended to allow for flexibility 
 in the navigation task and provide a way to easily specify complex robot behaviors, including recovery.
 
-Consider checking out the :ref:`groot_introduction` tutorial for using Groot to visualize and modify behavior trees.
+Consider checking out the tutorial :ref:`groot_introduction` (Humble) / :ref:`groot2_introduction` (Jazzy and newer) for using Groot to visualize and modify behavior trees.
 
 Make sure to review all parameters for non-default navigator plugins not discussed on this page (e.g. ``CoverageNavigator`` or custom additions).
 

diff --git a/configuration/packages/configuring-bt-xml.rst b/configuration/packages/configuring-bt-xml.rst
@@ -11,7 +11,7 @@ Check this introduction_ to learn how behavior trees work and the difference bet
 
 .. _introduction: https://www.behaviortree.dev/bt_basics/
 
-Consider checking out the :ref:`groot_introduction` tutorial for using Groot to visualize and modify behavior trees.
+Consider checking out the tutorial :ref:`groot_introduction` (Humble) / :ref:`groot2_introduction` (Jazzy and newer) for using Groot to visualize and modify behavior trees.
 
 Action Plugins
 **************

diff --git a/tutorials/docs/images/Groot2/bt_w_replanning_and_recovery.png b/tutorials/docs/images/Groot2/bt_w_replanning_and_recovery.png
diff --git a/tutorials/docs/images/Groot2/editing_bt.png b/tutorials/docs/images/Groot2/editing_bt.png
diff --git a/tutorials/docs/images/Groot2/groot_bt_editor.png b/tutorials/docs/images/Groot2/groot_bt_editor.png
diff --git a/tutorials/docs/images/Groot2/groot_create_custom_node.png b/tutorials/docs/images/Groot2/groot_create_custom_node.png
diff --git a/tutorials/docs/images/Groot2/groot_interactive_node_creation.png b/tutorials/docs/images/Groot2/groot_interactive_node_creation.png
diff --git a/tutorials/docs/images/Groot2/groot_new_node.png b/tutorials/docs/images/Groot2/groot_new_node.png
diff --git a/tutorials/docs/images/Groot2/groot_preferences.png b/tutorials/docs/images/Groot2/groot_preferences.png
diff --git a/tutorials/docs/images/Groot2/groot_with_nav2_custom_nodes.png b/tutorials/docs/images/Groot2/groot_with_nav2_custom_nodes.png
diff --git a/tutorials/docs/using_groot.rst b/tutorials/docs/using_groot.rst
@@ -42,7 +42,7 @@ Visualize Behavior Trees
 
 To display a Behavior Tree like that in :numref:`groot_nav2_default_bt`, we will first start the Groot executable.
 Out of the box, Groot can only display Behavior Trees and nodes that are from the defaults in BT.CPP, since it does not know anything about Nav2 or your other projects.
-Therefore, we must point Groot to our palette, or index, of Nav2 / custom behavior tree nodes:
+Therefore, we must point Groot to our palette, or index of Nav2 / custom behavior tree nodes:
 
 1. Open Groot in editor mode. Now, Groot should look like in :numref:`groot_bt_editor`.
 2. Select the `Load palette from file` option either via the context menu or the import icon in the top middle of the menu bar. 

diff --git a/tutorials/docs/using_groot2.rst b/tutorials/docs/using_groot2.rst
@@ -0,0 +1,115 @@
+.. _groot2_introduction:
+
+Groot2 - Interacting with Behavior Trees
+****************************************
+
+- `Overview`_ 
+- `Visualize Behavior Trees`_
+- `Edit Behavior Trees`_
+- `Adding A Custom Node`_
+
+Overview
+========
+
+`Groot2 <https://www.behaviortree.dev/groot/>`_ is the companion application of the `BehaviorTree.CPP <https://github.com/BehaviorTree/BehaviorTree.CPP>`_ library used to create, edit, and visualize behavior trees.
+Behavior Trees are deeply integrated into Nav2, used as the main method of orchestrating task server logic across a complex navigation and autonomy stack.
+Behavior Trees, in short BTs, consist of many nodes completing different tasks and control the flow of logic, similar to a Hierarchical or Finite State Machine, but organized in a tree structure.
+These nodes are of types: `Action`, `Condition`, `Control`, or `Decorator`, and are described in more detail in :ref:`concepts` and `BehaviorTree.CPP <https://www.behaviortree.dev/docs/learn-the-basics/BT_basics#types-of-nodes>`_.
+
+:ref:`writing_new_nbt_plugin` offers a well written example of creating a simple ``Action`` node if creating new BT nodes is of interest. This tutorial will focus solely on launching Groot2, visualizing a Behavior Tree, and modifying that tree for a given customization, assuming a library of BT nodes. Luckily, Nav2 provides a robust number of BT nodes for your use out of the box, enumerated in :ref:`plugins`.
+
+A BT configuration file in BehaviorTree.CPP is an XML file. This is used to dynamically load the BT node plugins at run-time from the appropriate libraries mapped to their names. The XML format is defined `in detail here <https://www.behaviortree.dev/docs/learn-the-basics/xml_format/>`_. Therefore, Groot2 needs to have a list of nodes it has access to and important metadata about them like their type and ports (or parameters). We refer to this as the "palette" of nodes later in the tutorial.
+
+Note: Before ROS 2 Humble, live Groot behavior tree monitoring during execution was supported in Nav2. This was removed due to buggy support in BT.CPP / Groot for changing behavior trees on the fly, see :ref:`galactic_migration` for more details.
+
+Visualize Behavior Trees
+========================
+
+To display a Behavior Tree like that in :numref:`groot2_nav2_default_bt`, we will first start the Groot2 executable.
+Out of the box, Groot2 can only display Behavior Trees and nodes that are from the defaults in BT.CPP, since it does not know anything about Nav2 or your other projects.
+Therefore, we must point Groot2 to our palette, or index of Nav2 / custom behavior tree nodes:
+
+1. Open Groot2 in editor mode. Now, Groot2 should look like in :numref:`groot2_bt_editor`.
+2. Select the `Import Models from file` option either via the import icon in the Models panel.
+3. Open the file `/path/to/navigation2/nav2_behavior_tree/nav2_tree_nodes.xml` to import all the custom behavior tree nodes used for navigation. This is the palette of Nav2 custom behavior tree nodes. Now, Groot2 should look like in :numref:`groot2_bt_editor_with_nodes`.
+4. Select `Load a project or a single XML file` option via the file icon next to the word "Project" in the top left corner.
+5. Browse the tree you want to visualize, then select `OK`. The Nav2 BTs exist in `/path/to/navigation2/nav2_bt_navigator/behavior_trees/`
+
++-----------------------------------------------------------+-----------------------------------------------------------+
+| .. figure:: images/Groot2/groot_bt_editor.png             | .. figure:: images/Groot2/groot_with_nav2_custom_nodes.png|
+|   :name: groot2_bt_editor                                 |   :name: groot2_bt_editor_with_nodes                      |
+|                                                           |                                                           |
+|   Default Editor View                                     |   Editor with Custom Nodes loaded in blue                 |
++-----------------------------------------------------------+-----------------------------------------------------------+
+
+If you select the default tree `navigate_w_replanning_and_recovery.xml`, then a Groot2 editor should look like :numref:`groot2_nav2_default_bt`.
+
++-----------------------------------------------------------+
+| .. figure:: images/Groot2/bt_w_replanning_and_recovery.png|
+|   :name: groot2_nav2_default_bt                           |
+|                                                           |
+|   Full Nav2 Default BehaviorTree                          |
++-----------------------------------------------------------+
+
+You can also check/uncheck the Node visualization part in the preferences to better visualize the tree.
+
++-----------------------------------------------------------+
+| .. figure:: images/Groot2/groot_preferences.png           |
+|   :name: groot2_preferences                               |
+|                                                           |
+|   Preferences for Groot2                                  |
++-----------------------------------------------------------+
+
+
+.. note::
+  If a tree cannot be visualized because some nodes are missing in the palette, you might need to add it to your palette. While we try to keep Nav2's BT nodes and palettes in sync, if you notice one is missing, please file a ticket or pull request and we should have that updated quickly.
+
+
+Edit Behavior Trees
+===================
+
+Now that you have a Nav2 BT open in Groot2 in editor mode, you should be able to trivially modify it using the GUI.
+Starting from a screen like that shown in :numref:`groot2_nav2_default_bt`, you can pull in new nodes from the side panel to add them to the workspace.
+You may then connect the nodes using a "drag and drop" motion between the node's input and output ports to assemble the new nodes into the tree.
+
+If you select a given node, you can change metadata about it such as its name or values of parameterizable ports. When you're done modifying, simply save the new configuration file and use that on your robot the next time!
+
++-----------------------------------------------------------+
+| .. figure:: images/Groot2/editing_bt.png                  |
+|   :name: groot2_editing_bt                                |
+|                                                           |
+|   Editing a Behavior Tree                                 |
++-----------------------------------------------------------+
+
+
+Adding A Custom Node
+====================
+
+Each node in the behavior tree holds a specialized function.
+Sometimes, its useful to create new nodes and add them to your palette during the design process - perhaps before the implementations themselves exist.
+This helps designers abstract away the implementation specifics of the nodes from the higher level logic of the tree itself and how they'd like to interact with a given node (e.g. type, ports, etc).
+Within Groot2, you may create new custom nodes to add to your tree and export these new nodes back to your palette.
+Implementing the node itself needs to be done separately from Groot2, which is described in :ref:`writing_new_nbt_plugin`.
+
++-----------------------------------------------------------+
+| .. figure:: images/Groot2/groot_create_custom_node.png    |
+|   :name: groot2_create_custom_node                        |
+|   :width: 50%                                             |
+|                                                           |
+|   Create a new Custom Node                                |
++-----------------------------------------------------------+
+
+Creating a new custom node can be started by clicking the red marked icon in :numref:`groot2_create_custom_node`, while Groot2 is in Editor mode.
+This should load a new window, similar to :numref:`groot2_interactive_node_creation`. 
+In this new window, it asks you to fill in the metadata about this new node, in order to create it. 
+It will ask you for standard information such as port name, type of node, and any optional ports for parameterization or access to blackboard variables.
+
+After completing, select `OK` in :numref:`groot2_interactive_node_creation`, the new custom node should appear in blue in the `TreeNode Palette` as in :numref:`groot2_new_node`.
+
++--------------------------------------------------------------+--------------------------------------------------------------+
+| .. figure:: images/Groot2/groot_interactive_node_creation.png| .. figure:: images/Groot2/groot_new_node.png                 |
+|   :name: groot2_interactive_node_creation                    |   :name: groot2_new_node                                     |
+|                                                              |   :width: 180%                                               |
+|                                                              |                                                              |
+|   UI to describing new Nodes                                 |   The New Custom Node                                        |
++--------------------------------------------------------------+--------------------------------------------------------------+
diff --git a/tutorials/index.rst b/tutorials/index.rst
@@ -13,6 +13,7 @@ Nav2 Tutorials
    docs/navigation2_with_stvl.rst
    docs/navigation2_with_gps.rst
    docs/using_groot.rst
+   docs/using_groot2.rst
    docs/integrating_vio.rst
    docs/navigation2_dynamic_point_following.rst
    docs/navigation2_with_keepout_filter.rst