explore::ExploreFrontier Class Reference

A class that will identify frontiers in a partially explored map. More...

#include <explore_frontier.h>

List of all members.

Public Member Functions
	ExploreFrontier ()
virtual bool	getExplorationGoals (costmap_2d::Costmap2DROS &costmap, tf::Stamped< tf::Pose > robot_pose, navfn::NavfnROS *planner, std::vector< geometry_msgs::Pose > &goals, double cost_scale, double orientation_scale, double gain_scale)
	Returns a list of frontiers, sorted by the planners estimated cost to visit each frontier.
virtual bool	getFrontiers (costmap_2d::Costmap2DROS &costmap, std::vector< geometry_msgs::Pose > &frontiers)
	Returns all frontiers.
virtual void	getVisualizationMarkers (std::vector< visualization_msgs::Marker > &markers)
	Returns markers representing all frontiers.
virtual	~ExploreFrontier ()
Protected Member Functions
virtual void	findFrontiers (costmap_2d::Costmap2DROS &costmap_)
	Finds frontiers and populates frontiers_.
virtual float	getFrontierCost (const Frontier &frontier)
	Calculates cost to explore frontier.
virtual float	getFrontierGain (const Frontier &frontier, double map_resolution)
	Calculates potential information gain of exploring frontier.
virtual double	getOrientationChange (const Frontier &frontier, const tf::Stamped< tf::Pose > &robot_pose)
	Calculates how much the robot would have to turn to face this frontier.
Protected Attributes
std::vector< Frontier >	frontiers_
Private Attributes
float	costmapResolution_
uint	lastMarkerCount_
nav_msgs::OccupancyGrid	map_
navfn::NavfnROS *	planner_

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Detailed Description

A class that will identify frontiers in a partially explored map.

Definition at line 79 of file explore_frontier.h.

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Constructor & Destructor Documentation

explore::ExploreFrontier::ExploreFrontier

(

)

Definition at line 50 of file explore_frontier.cpp.

explore::ExploreFrontier::~ExploreFrontier

(

)

[virtual]

Definition at line 58 of file explore_frontier.cpp.

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Member Function Documentation

void explore::ExploreFrontier::findFrontiers

(

costmap_2d::Costmap2DROS &

costmap_

)

[protected, virtual]

Finds frontiers and populates frontiers_.

Parameters:

costmap

The costmap to search for frontiers

Definition at line 163 of file explore_frontier.cpp.

bool explore::ExploreFrontier::getExplorationGoals	(	costmap_2d::Costmap2DROS &	costmap,
		tf::Stamped< tf::Pose >	robot_pose,
		navfn::NavfnROS *	planner,
		std::vector< geometry_msgs::Pose > &	goals,
		double	cost_scale,
		double	orientation_scale,
		double	gain_scale
	)			[virtual]

Returns a list of frontiers, sorted by the planners estimated cost to visit each frontier.

Parameters:

	costmap	The costmap to search for frontiers
	start	The current position of the robot
	goals	Will be filled with sorted list of current goals
	planner	A planner to evaluate the cost of going to any frontier
	potential_scale	A scaling for the potential to a frontier goal point for the frontier's cost
	orientation_scale	A scaling for the change in orientation required to get to a goal point for the frontier's cost
	gain_scale	A scaling for the expected information gain to get to a goal point for the frontier's cost

Returns:

True if at least one frontier was found

The frontiers are weighted by a simple cost function, which prefers frontiers which are large and close: frontier cost = travel cost / frontier size

Several different positions are evaluated for each frontier. This improves the robustness of goals which may lie near other obstacles which would prevent planning.

Definition at line 101 of file explore_frontier.cpp.

float explore::ExploreFrontier::getFrontierCost

(

const Frontier &

frontier

)

[protected, virtual]

Calculates cost to explore frontier.

Parameters:

frontier

to evaluate

Definition at line 78 of file explore_frontier.cpp.

float explore::ExploreFrontier::getFrontierGain	(	const Frontier &	frontier,
		double	map_resolution
	)			[protected, virtual]

Calculates potential information gain of exploring frontier.

Parameters:

frontier

to evaluate

Definition at line 97 of file explore_frontier.cpp.

bool explore::ExploreFrontier::getFrontiers	(	costmap_2d::Costmap2DROS &	costmap,
		std::vector< geometry_msgs::Pose > &	frontiers
	)			[virtual]

Returns all frontiers.

Parameters:

	costmap	The costmap to search for frontiers
	frontiers	Will be filled with current frontiers

Returns:

True if at least one frontier was found

Definition at line 63 of file explore_frontier.cpp.

double explore::ExploreFrontier::getOrientationChange	(	const Frontier &	frontier,
		const tf::Stamped< tf::Pose > &	robot_pose
	)			[protected, virtual]

Calculates how much the robot would have to turn to face this frontier.

Parameters:

	frontier	to evaluate
	robot_pose	current pose

Definition at line 88 of file explore_frontier.cpp.

virtual void explore::ExploreFrontier::getVisualizationMarkers

(

std::vector< visualization_msgs::Marker > &

markers

)

[virtual]

Returns markers representing all frontiers.

Parameters:

markers

All markers will be added to this vector

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Member Data Documentation

float explore::ExploreFrontier::costmapResolution_ [private]

Definition at line 84 of file explore_frontier.h.

std::vector<Frontier> explore::ExploreFrontier::frontiers_ [protected]

Definition at line 88 of file explore_frontier.h.

uint explore::ExploreFrontier::lastMarkerCount_ [private]

Definition at line 83 of file explore_frontier.h.

nav_msgs::OccupancyGrid explore::ExploreFrontier::map_ [private]

Definition at line 81 of file explore_frontier.h.

navfn::NavfnROS* explore::ExploreFrontier::planner_ [private]

Definition at line 86 of file explore_frontier.h.

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

• explore_frontier.h
• explore_frontier.cpp