nav2_behavior_tree::BehaviorTreeEngine Class Reference

A class to create and handle behavior trees. More...

#include <nav2_behavior_tree/include/nav2_behavior_tree/behavior_tree_engine.hpp>

Public Member Functions
	BehaviorTreeEngine (const std::vector< std::string > &plugin_libraries, nav2::LifecycleNode::SharedPtr node)
	A constructor for nav2_behavior_tree::BehaviorTreeEngine. More...
BtStatus	run (BT::Tree *tree, std::function< void()> onLoop, std::function< bool()> cancelRequested, std::chrono::milliseconds loopTimeout=std::chrono::milliseconds(10))
	Function to execute a BT at a specific rate. More...
BT::Tree	createTreeFromText (const std::string &xml_string, BT::Blackboard::Ptr blackboard)
	Function to create a BT from a XML string. More...
BT::Tree	createTreeFromFile (const std::string &file_path, BT::Blackboard::Ptr blackboard)
	Function to create a BT from an XML file. More...
std::string	extractBehaviorTreeID (const std::string &file_or_id)
	Extract BehaviorTree ID from BT file path or BT ID. More...
BT::Tree	createTree (const std::string &tree_id, BT::Blackboard::Ptr blackboard)
	Function to create a BT from a BehaviorTree ID. More...
void	addGrootMonitoring (BT::Tree *tree, uint16_t server_port)
	Add Groot2 monitor to publish BT status changes. More...
void	resetGrootMonitor ()
	Reset groot monitor.
void	registerTreeFromFile (const std::string &file_path)
	Function to register a BT from an XML file. More...
void	haltAllActions (BT::Tree &tree)
	Function to explicitly reset all BT nodes to initial state. More...

Protected Attributes
BT::BehaviorTreeFactory	factory_
rclcpp::Clock::SharedPtr	clock_
std::unique_ptr< BT::Groot2Publisher >	groot_monitor_

Detailed Description

A class to create and handle behavior trees.

Definition at line 43 of file behavior_tree_engine.hpp.

Constructor & Destructor Documentation

BehaviorTreeEngine()

nav2_behavior_tree::BehaviorTreeEngine::BehaviorTreeEngine ( const std::vector< std::string > &  plugin_libraries, nav2::LifecycleNode::SharedPtr  node  )

explicit

A constructor for nav2_behavior_tree::BehaviorTreeEngine.

Parameters

plugin_libraries

vector of BT plugin library names to load

Definition at line 32 of file behavior_tree_engine.cpp.

Member Function Documentation

addGrootMonitoring()

void nav2_behavior_tree::BehaviorTreeEngine::addGrootMonitoring	(	BT::Tree *	tree,
		uint16_t	server_port
	)

Add Groot2 monitor to publish BT status changes.

Parameters

tree	BT to monitor
server_port	Groot2 Server port, first of the pair (server_port, publisher_port)

Definition at line 159 of file behavior_tree_engine.cpp.

createTree()

BT::Tree nav2_behavior_tree::BehaviorTreeEngine::createTree	(	const std::string &	tree_id,
		BT::Blackboard::Ptr	blackboard
	)

Function to create a BT from a BehaviorTree ID.

Parameters

tree_id	BehaviorTree ID
blackboard	Blackboard for BT

Returns

BT::Tree Created behavior tree

Definition at line 144 of file behavior_tree_engine.cpp.

createTreeFromFile()

BT::Tree nav2_behavior_tree::BehaviorTreeEngine::createTreeFromFile	(	const std::string &	file_path,
		BT::Blackboard::Ptr	blackboard
	)

Function to create a BT from an XML file.

Parameters

file_path	Path to BT XML file
blackboard	Blackboard for BT

Returns

BT::Tree Created behavior tree

Definition at line 99 of file behavior_tree_engine.cpp.

createTreeFromText()

BT::Tree nav2_behavior_tree::BehaviorTreeEngine::createTreeFromText	(	const std::string &	xml_string,
		BT::Blackboard::Ptr	blackboard
	)

Function to create a BT from a XML string.

Parameters

xml_string	XML string representing BT
blackboard	Blackboard for BT

Returns

BT::Tree Created behavior tree

Definition at line 91 of file behavior_tree_engine.cpp.

extractBehaviorTreeID()

std::string nav2_behavior_tree::BehaviorTreeEngine::extractBehaviorTreeID

(

const std::string &

file_or_id

)

Extract BehaviorTree ID from BT file path or BT ID.

Parameters

file_or_id

Returns

std::string

Definition at line 106 of file behavior_tree_engine.cpp.

haltAllActions()

void nav2_behavior_tree::BehaviorTreeEngine::haltAllActions

(

BT::Tree &

tree

)

Function to explicitly reset all BT nodes to initial state.

Parameters

tree	Tree to halt

Definition at line 181 of file behavior_tree_engine.cpp.

registerTreeFromFile()

void nav2_behavior_tree::BehaviorTreeEngine::registerTreeFromFile

(

const std::string &

file_path

)

Function to register a BT from an XML file.

Register a tree from an XML file and return the tree.

Parameters

file_path

Path to BT XML file

Definition at line 152 of file behavior_tree_engine.cpp.

run()

BtStatus nav2_behavior_tree::BehaviorTreeEngine::run	(	BT::Tree *	tree,
		std::function< void()>	onLoop,
		std::function< bool()>	cancelRequested,
		std::chrono::milliseconds	loopTimeout = std::chrono::milliseconds(10)
	)

Function to execute a BT at a specific rate.

Parameters

tree	BT to execute
onLoop	Function to execute on each iteration of BT execution
cancelRequested	Function to check if cancel was requested during BT execution
loopTimeout	Time period for each iteration of BT execution

Returns

nav2_behavior_tree::BtStatus Status of BT execution

Definition at line 51 of file behavior_tree_engine.cpp.

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The documentation for this class was generated from the following files:

• nav2_behavior_tree/include/nav2_behavior_tree/behavior_tree_engine.hpp
• nav2_behavior_tree/src/behavior_tree_engine.cpp