rm_decision

a robot decision module base on BehaviorTree.CPP and ROS2

1. Install BehaviorTree.CPP

1.1 Install from source

1.2 Install Groot2

NOTICE

• There are several differences between the official source and that in this repository. I modify the reactive_fallback.cpp(342ce3029e37c8836c0a53ca3e52a975de72cc79). See more details in the commit history.

• This documentation is a digest of the official documentation. For more details, please refer to the official documentation.

• Server-client mode is recommended for the communication between the behavior tree and the robot control module.

2. A INTRO

Basic Idea

Unlike a Finite State Machine, a behavior Tree is a tree of hierarchical nodes that controls the flow of execution of “tasks”.

Everytime the tree is ticked, the tree will be traversed from the root node to the leaf node, and the leaf node will return a status code to the parent node, and the parent node will return a status code to the grandparent node, and so on, until the root node is reached.

Though it is easy to understand, there are still some mistakes that are easy to make. And the only way to avoid these mistakes is to make mistakes and learn from them, at least for me.

3. Learning From a Detailed Example

Tree Structure

The tree structure is defined in a xml file. A recommended way to create a tree is to use the Groot2, a graphical editor for BehaviorTree.CPP.