ompl::geometric::SPARSdb Class Reference

SPArse Roadmap Spanner Version 2.0 More...

#include <ompl/tools/thunder/SPARSdb.h>

Inheritance diagram for ompl::geometric::SPARSdb:

Classes
struct	CandidateSolution
	Struct for passing around partially solved solutions. More...
class	CustomVisitor
struct	edge_collision_state_t
class	edgeWeightMap
class	foundGoalException
struct	InterfaceData
	Interface information storage class, which does bookkeeping for criterion four. More...
struct	InterfaceHashStruct
struct	vertex_color_t
struct	vertex_interface_data_t
struct	vertex_state_t

Public Types
enum	GuardType {   START, GOAL, COVERAGE, CONNECTIVITY,   INTERFACE, QUALITY }
	Enumeration which specifies the reason a guard is added to the spanner.
enum	EdgeCollisionState { NOT_CHECKED, IN_COLLISION, FREE }
	Possible collision states of an edge.
using	VertexIndexType = unsigned long int
	The type used internally for representing vertex IDs.
using	VertexPair = std::pair< VertexIndexType, VertexIndexType >
	Pair of vertices which support an interface.
using	InterfaceHash = std::unordered_map< VertexPair, InterfaceData >
	the hash which maps pairs of neighbor points to pairs of states
using	VertexProperties = boost::property< vertex_state_t, base::State *, boost::property< boost::vertex_predecessor_t, VertexIndexType, boost::property< boost::vertex_rank_t, VertexIndexType, boost::property< vertex_color_t, GuardType, boost::property< vertex_interface_data_t, InterfaceHashStruct > >> >>
	The underlying roadmap graph. More...
using	EdgeProperties = boost::property< boost::edge_weight_t, double, boost::property< edge_collision_state_t, int > >
using	Graph = boost::adjacency_list< boost::vecS, boost::vecS, boost::undirectedS, VertexProperties, EdgeProperties >
using	Vertex = boost::graph_traits< Graph >::vertex_descriptor
	Vertex in Graph.
using	Edge = boost::graph_traits< Graph >::edge_descriptor
	Edge in Graph.
using	EdgeCollisionStateMap = boost::property_map< Graph, edge_collision_state_t >::type
	Access map that stores the lazy collision checking status of each edge.
Public Types inherited from ompl::base::Planner
using	PlannerProgressProperty = std::function< std::string()>
	Definition of a function which returns a property about the planner's progress that can be queried by a benchmarking routine.
using	PlannerProgressProperties = std::map< std::string, PlannerProgressProperty >
	A dictionary which maps the name of a progress property to the function to be used for querying that property.

Public Member Functions
	SPARSdb (const base::SpaceInformationPtr &si)
	Constructor.
	~SPARSdb () override
	Destructor.
void	setProblemDefinition (const base::ProblemDefinitionPtr &pdef) override
void	setStretchFactor (double t)
	Sets the stretch factor.
void	setSparseDeltaFraction (double D)
	Sets vertex visibility range as a fraction of max. extent.
void	setDenseDeltaFraction (double d)
	Sets interface support tolerance as a fraction of max. extent.
void	setMaxFailures (unsigned int m)
	Sets the maximum failures until termination.
unsigned int	getMaxFailures () const
	Retrieve the maximum consecutive failure limit.
double	getDenseDeltaFraction () const
	Retrieve the dense graph interface support delta.
double	getSparseDeltaFraction () const
	Retrieve the sparse graph visibility range delta.
double	getStretchFactor () const
	Retrieve the spanner's set stretch factor.
bool	getGuardSpacingFactor (double pathLength, double &numGuards, double &spacingFactor)
bool	getGuardSpacingFactor (double pathLength, int &numGuards, double &spacingFactor)
	Calculate the distance that should be used in inserting nodes into the db. More...
bool	addPathToRoadmap (const base::PlannerTerminationCondition &ptc, ompl::geometric::PathGeometric &solutionPath)
bool	checkStartGoalConnection (ompl::geometric::PathGeometric &solutionPath)
bool	addStateToRoadmap (const base::PlannerTerminationCondition &ptc, base::State *newState)
base::PlannerStatus	solve (const base::PlannerTerminationCondition &ptc) override
	Function that can solve the motion planning problem. This function can be called multiple times on the same problem, without calling clear() in between. This allows the planner to continue work for more time on an unsolved problem, for example. Start and goal states from the currently specified ProblemDefinition are cached. This means that between calls to solve(), input states are only added, not removed. When using PRM as a multi-query planner, the input states should be however cleared, without clearing the roadmap itself. This can be done using the clearQuery() function.
void	clearQuery () override
	Clear the query previously loaded from the ProblemDefinition. Subsequent calls to solve() will reuse the previously computed roadmap, but will clear the set of input states constructed by the previous call to solve(). This enables multi-query functionality for PRM.
void	clear () override
	Clear all internal datastructures. Planner settings are not affected. Subsequent calls to solve() will ignore all previous work.
template<template< typename T > class NN>
void	setNearestNeighbors ()
	Set a different nearest neighbors datastructure.
bool	getSimilarPaths (int nearestK, const base::State *start, const base::State *goal, CandidateSolution &candidateSolution, const base::PlannerTerminationCondition &ptc)
	Search the roadmap for the best path close to the given start and goal states that is valid. More...
void	setup () override
	Perform extra configuration steps, if needed. This call will also issue a call to ompl::base::SpaceInformation::setup() if needed. This must be called before solving.
const Graph &	getRoadmap () const
	Retrieve the computed roadmap.
unsigned int	getNumVertices () const
	Get the number of vertices in the sparse roadmap.
unsigned int	getNumEdges () const
	Get the number of edges in the sparse roadmap.
unsigned int	getNumConnectedComponents () const
	Get the number of disjoint sets in the sparse roadmap.
unsigned int	getNumPathInsertionFailed () const
	Get the number of times a path was inserted into the database and it failed to have connectivity.
unsigned int	getNumConsecutiveFailures () const
	description
long unsigned int	getIterations () const
	Get the number of iterations the algorithm performed.
bool	convertVertexPathToStatePath (std::vector< Vertex > &vertexPath, const base::State *actualStart, const base::State *actualGoal, CandidateSolution &candidateSolution, bool disableCollisionWarning=false)
	Convert astar results to correctly ordered path. More...
void	getPlannerData (base::PlannerData &data) const override
	Get information about the current run of the motion planner. Repeated calls to this function will update data (only additions are made). This is useful to see what changed in the exploration datastructure, between calls to solve(), for example (without calling clear() in between).
void	setPlannerData (const base::PlannerData &data)
	Set the sparse graph from file. More...
bool	reachedFailureLimit () const
	Returns whether we have reached the iteration failures limit, maxFailures_.
void	printDebug (std::ostream &out=std::cout) const
	Print debug information about planner.
void	clearEdgeCollisionStates ()
	Clear all past edge state information about in collision or not.
Public Member Functions inherited from ompl::base::Planner
	Planner (const Planner &)=delete
Planner &	operator= (const Planner &)=delete
	Planner (SpaceInformationPtr si, std::string name)
	Constructor.
virtual	~Planner ()=default
	Destructor.
template<class T >
T *	as ()
	Cast this instance to a desired type. More...
template<class T >
const T *	as () const
	Cast this instance to a desired type. More...
const SpaceInformationPtr &	getSpaceInformation () const
	Get the space information this planner is using.
const ProblemDefinitionPtr &	getProblemDefinition () const
	Get the problem definition the planner is trying to solve.
ProblemDefinitionPtr &	getProblemDefinition ()
	Get the problem definition the planner is trying to solve.
const PlannerInputStates &	getPlannerInputStates () const
	Get the planner input states.
virtual void	setProblemDefinition (const ProblemDefinitionPtr &pdef)
	Set the problem definition for the planner. The problem needs to be set before calling solve(). Note: If this problem definition replaces a previous one, it may also be necessary to call clear() or clearQuery().
PlannerStatus	solve (const PlannerTerminationConditionFn &ptc, double checkInterval)
	Same as above except the termination condition is only evaluated at a specified interval.
PlannerStatus	solve (double solveTime)
	Same as above except the termination condition is solely a time limit: the number of seconds the algorithm is allowed to spend planning.
const std::string &	getName () const
	Get the name of the planner.
void	setName (const std::string &name)
	Set the name of the planner.
const PlannerSpecs &	getSpecs () const
	Return the specifications (capabilities of this planner)
virtual void	checkValidity ()
	Check to see if the planner is in a working state (setup has been called, a goal was set, the input states seem to be in order). In case of error, this function throws an exception.
bool	isSetup () const
	Check if setup() was called for this planner.
ParamSet &	params ()
	Get the parameters for this planner.
const ParamSet &	params () const
	Get the parameters for this planner.
const PlannerProgressProperties &	getPlannerProgressProperties () const
	Retrieve a planner's planner progress property map.
virtual void	printProperties (std::ostream &out) const
	Print properties of the motion planner.
virtual void	printSettings (std::ostream &out) const
	Print information about the motion planner's settings.

Protected Member Functions
void	freeMemory ()
	Free all the memory allocated by the planner.
void	checkQueryStateInitialization ()
	Check that the query vertex is initialized (used for internal nearest neighbor searches)
bool	checkAddCoverage (const base::State *qNew, std::vector< Vertex > &visibleNeighborhood)
	Checks to see if the sample needs to be added to ensure coverage of the space.
bool	checkAddConnectivity (const base::State *qNew, std::vector< Vertex > &visibleNeighborhood)
	Checks to see if the sample needs to be added to ensure connectivity.
bool	checkAddInterface (const base::State *qNew, std::vector< Vertex > &graphNeighborhood, std::vector< Vertex > &visibleNeighborhood)
	Checks to see if the current sample reveals the existence of an interface, and if so, tries to bridge it.
bool	checkAddPath (Vertex v)
	Checks vertex v for short paths through its region and adds when appropriate.
void	resetFailures ()
	A reset function for resetting the failures count.
void	findGraphNeighbors (base::State *state, std::vector< Vertex > &graphNeighborhood, std::vector< Vertex > &visibleNeighborhood)
	Finds visible nodes in the graph near state.
bool	findGraphNeighbors (const base::State *state, std::vector< Vertex > &graphNeighborhood)
	Finds nodes in the graph near state NOTE: note tested for visibility. More...
void	approachGraph (Vertex v)
	Approaches the graph from a given vertex.
Vertex	findGraphRepresentative (base::State *st)
	Finds the representative of the input state, st
void	findCloseRepresentatives (base::State *workState, const base::State *qNew, Vertex qRep, std::map< Vertex, base::State * > &closeRepresentatives, const base::PlannerTerminationCondition &ptc)
	Finds representatives of samples near qNew_ which are not his representative.
void	updatePairPoints (Vertex rep, const base::State *q, Vertex r, const base::State *s)
	High-level method which updates pair point information for repV_ with neighbor r.
void	computeVPP (Vertex v, Vertex vp, std::vector< Vertex > &VPPs)
	Computes all nodes which qualify as a candidate v" for v and vp.
void	computeX (Vertex v, Vertex vp, Vertex vpp, std::vector< Vertex > &Xs)
	Computes all nodes which qualify as a candidate x for v, v', and v".
VertexPair	index (Vertex vp, Vertex vpp)
	Rectifies indexing order for accessing the vertex data.
InterfaceData &	getData (Vertex v, Vertex vp, Vertex vpp)
	Retrieves the Vertex data associated with v,vp,vpp.
void	distanceCheck (Vertex rep, const base::State *q, Vertex r, const base::State *s, Vertex rp)
	Performs distance checking for the candidate new state, q against the current information.
void	abandonLists (base::State *st)
	When a new guard is added at state st, finds all guards who must abandon their interface information and deletes that information.
Vertex	addGuard (base::State *state, GuardType type)
	Construct a guard for a given state (state) and store it in the nearest neighbors data structure.
void	connectGuards (Vertex v, Vertex vp)
	Connect two guards in the roadmap.
bool	getPaths (const std::vector< Vertex > &candidateStarts, const std::vector< Vertex > &candidateGoals, const base::State *actualStart, const base::State *actualGoal, CandidateSolution &candidateSolution, const base::PlannerTerminationCondition &ptc)
	Check if there exists a solution, i.e., there exists a pair of milestones such that the first is in start and the second is in goal, and the two milestones are in the same connected component. If a solution is found, the path is saved.
bool	lazyCollisionSearch (const Vertex &start, const Vertex &goal, const base::State *actualStart, const base::State *actualGoal, CandidateSolution &candidateSolution, const base::PlannerTerminationCondition &ptc)
	Repeatidly search through graph for connection then check for collisions then repeat. More...
bool	lazyCollisionCheck (std::vector< Vertex > &vertexPath, const base::PlannerTerminationCondition &ptc)
	Check recalled path for collision and disable as needed.
void	checkForSolution (const base::PlannerTerminationCondition &ptc, base::PathPtr &solution)
bool	constructSolution (Vertex start, Vertex goal, std::vector< Vertex > &vertexPath) const
	Given two milestones from the same connected component, construct a path connecting them and set it as the solution. More...
bool	sameComponent (Vertex m1, Vertex m2)
	Check if two milestones (m1 and m2) are part of the same connected component. This is not a const function since we use incremental connected components from boost.
double	distanceFunction (const Vertex a, const Vertex b) const
	Compute distance between two milestones (this is simply distance between the states of the milestones)
Protected Member Functions inherited from ompl::base::Planner
template<typename T , typename PlannerType , typename SetterType , typename GetterType >
void	declareParam (const std::string &name, const PlannerType &planner, const SetterType &setter, const GetterType &getter, const std::string &rangeSuggestion="")
	This function declares a parameter for this planner instance, and specifies the setter and getter functions.
template<typename T , typename PlannerType , typename SetterType >
void	declareParam (const std::string &name, const PlannerType &planner, const SetterType &setter, const std::string &rangeSuggestion="")
	This function declares a parameter for this planner instance, and specifies the setter function.
void	addPlannerProgressProperty (const std::string &progressPropertyName, const PlannerProgressProperty &prop)
	Add a planner progress property called progressPropertyName with a property querying function prop to this planner's progress property map.

Protected Attributes
base::ValidStateSamplerPtr	sampler_
	Sampler user for generating valid samples in the state space.
std::shared_ptr< NearestNeighbors< Vertex > >	nn_
	Nearest neighbors data structure.
Graph	g_
	Connectivity graph.
std::vector< Vertex >	startM_
	Array of start milestones.
std::vector< Vertex >	goalM_
	Array of goal milestones.
Vertex	queryVertex_
	Vertex for performing nearest neighbor queries.
double	stretchFactor_ {3.}
	Stretch Factor as per graph spanner literature (multiplicative bound on path quality)
double	sparseDeltaFraction_ {.25}
	Maximum visibility range for nodes in the graph as a fraction of maximum extent.
double	denseDeltaFraction_ {.001}
	Maximum range for allowing two samples to support an interface as a fraction of maximum extent.
unsigned int	maxFailures_ {5000u}
	The number of consecutive failures to add to the graph before termination.
unsigned int	numPathInsertionFailures_ {0u}
	Track how many solutions fail to have connectivity at end.
unsigned int	nearSamplePoints_
	Number of sample points to use when trying to detect interfaces.
PathSimplifierPtr	psimp_
	A path simplifier used to simplify dense paths added to the graph.
boost::property_map< Graph, boost::edge_weight_t >::type	edgeWeightProperty_
	Access to the weights of each Edge.
EdgeCollisionStateMap	edgeCollisionStateProperty_
	Access to the collision checking state of each Edge.
boost::property_map< Graph, vertex_state_t >::type	stateProperty_
	Access to the internal base::state at each Vertex.
boost::property_map< Graph, vertex_color_t >::type	colorProperty_
	Access to the colors for the vertices.
boost::property_map< Graph, vertex_interface_data_t >::type	interfaceDataProperty_
	Access to the interface pair information for the vertices.
boost::disjoint_sets< boost::property_map< Graph, boost::vertex_rank_t >::type, boost::property_map< Graph, boost::vertex_predecessor_t >::type >	disjointSets_
	Data structure that maintains the connected components.
RNG	rng_
	Random number generator.
bool	addedSolution_ {false}
	A flag indicating that a solution has been added during solve()
unsigned int	consecutiveFailures_ {0u}
	A counter for the number of consecutive failed iterations of the algorithm.
long unsigned int	iterations_ {0ul}
	A counter for the number of iterations of the algorithm.
double	sparseDelta_ {0.}
	Maximum visibility range for nodes in the graph.
double	denseDelta_ {0.}
	Maximum range for allowing two samples to support an interface.
std::vector< Vertex >	startVertexCandidateNeighbors_
	Used by getSimilarPaths.
std::vector< Vertex >	goalVertexCandidateNeighbors_
bool	verbose_ {false}
	Option to enable debugging output.
Protected Attributes inherited from ompl::base::Planner
SpaceInformationPtr	si_
	The space information for which planning is done.
ProblemDefinitionPtr	pdef_
	The user set problem definition.
PlannerInputStates	pis_
	Utility class to extract valid input states
std::string	name_
	The name of this planner.
PlannerSpecs	specs_
	The specifications of the planner (its capabilities)
ParamSet	params_
	A map from parameter names to parameter instances for this planner. This field is populated by the declareParam() function.
PlannerProgressProperties	plannerProgressProperties_
	A mapping between this planner's progress property names and the functions used for querying those progress properties.
bool	setup_
	Flag indicating whether setup() has been called.

Detailed Description

SPArse Roadmap Spanner Version 2.0

Short description

SPARSdb is a variant of the SPARS algorithm which removes the dependency on having the dense graph, D. It works through similar mechanics, but uses a different approach to identifying interfaces and computing shortest paths through said interfaces.

This version has been modified for use with Thunder

External documentation

A. Dobson, K. Bekris, Improving Sparse Roadmap Spanners, IEEE International Conference on Robotics and Automation (ICRA) May 2013. [PDF]

Definition at line 149 of file SPARSdb.h.

Member Typedef Documentation

EdgeProperties

using ompl::geometric::SPARSdb::EdgeProperties = boost::property<boost::edge_weight_t, double, boost::property<edge_collision_state_t, int> >

Wrapper for the double assigned to an edge as its weight property.

Definition at line 382 of file SPARSdb.h.

Graph

using ompl::geometric::SPARSdb::Graph = boost::adjacency_list<boost::vecS, boost::vecS, boost::undirectedS, VertexProperties, EdgeProperties>

The underlying boost graph type (undirected weighted-edge adjacency list with above properties).

Definition at line 387 of file SPARSdb.h.

VertexProperties

using ompl::geometric::SPARSdb::VertexProperties = boost::property< vertex_state_t, base::State *, boost::property< boost::vertex_predecessor_t, VertexIndexType, boost::property<boost::vertex_rank_t, VertexIndexType, boost::property<vertex_color_t, GuardType, boost::property<vertex_interface_data_t, InterfaceHashStruct> >> >>

The underlying roadmap graph.

Any BGL graph representation could be used here. Because we

expect the roadmap to be sparse (m<n^2), an adjacency_list is more appropriate than an adjacency_matrix. Edges are undirected.

Properties of vertices*

• vertex_state_t: an ompl::base::State* is required for OMPL
• vertex_predecessor_t: The incremental connected components algorithm requires it
• vertex_rank_t: The incremental connected components algorithm requires it
• vertex_color_t - TODO
• vertex_interface_data_t - needed by SPARS2 for maintainings its sparse properties

Note: If boost::vecS is not used for vertex storage, then there must also be a boost:vertex_index_t property manually added.

Properties of edges*

• edge_weight_t - cost/distance between two vertices
• edge_collision_state_t - used for lazy collision checking, determines if an edge has been checked already for collision. 0 = not checked/unknown, 1 = in collision, 2 = free Wrapper for the vertex's multiple as its property.

Definition at line 378 of file SPARSdb.h.

Member Function Documentation

checkForSolution()

void ompl::geometric::SPARSdb::checkForSolution ( const base::PlannerTerminationCondition &  ptc, base::PathPtr &  solution  )

protected

Thread that checks for solution

constructSolution()

bool ompl::geometric::SPARSdb::constructSolution ( Vertex  start, Vertex  goal, std::vector< Vertex > &  vertexPath  ) const

protected

Given two milestones from the same connected component, construct a path connecting them and set it as the solution.

Parameters

start
goal
vertexPath

Returns

true if candidate solution found

Definition at line 416 of file SPARSdb.cpp.

convertVertexPathToStatePath()

bool ompl::geometric::SPARSdb::convertVertexPathToStatePath	(	std::vector< Vertex > &	vertexPath,
		const base::State *	actualStart,
		const base::State *	actualGoal,
		CandidateSolution &	candidateSolution,
		bool	disableCollisionWarning = false
	)

Convert astar results to correctly ordered path.

Parameters

vertexPath	- in reverse
start	- actual start that is probably not included in new path
goal	- actual goal that is probably not included in new path
path	- returned solution
disableCollisionWarning	- if the func should ignore edges that are not checked

Returns

true on success

Definition at line 1654 of file SPARSdb.cpp.

findGraphNeighbors()

bool ompl::geometric::SPARSdb::findGraphNeighbors ( const base::State *  state, std::vector< Vertex > &  graphNeighborhood  )

protected

Finds nodes in the graph near state NOTE: note tested for visibility.

Parameters

state	- vertex to find neighbors around
result

Returns

false is no neighbors found

Definition at line 1293 of file SPARSdb.cpp.

getGuardSpacingFactor()

bool ompl::geometric::SPARSdb::getGuardSpacingFactor	(	double	pathLength,
		int &	numGuards,
		double &	spacingFactor
	)

Calculate the distance that should be used in inserting nodes into the db.

Parameters

path	length - from the trajectory
num	guards - the output result
spacing	factor - what fraction of the sparsedelta should be used in placing guards

Returns

Definition at line 577 of file SPARSdb.cpp.

getSimilarPaths()

bool ompl::geometric::SPARSdb::getSimilarPaths	(	int	nearestK,
		const base::State *	start,
		const base::State *	goal,
		CandidateSolution &	candidateSolution,
		const base::PlannerTerminationCondition &	ptc
	)

Search the roadmap for the best path close to the given start and goal states that is valid.

Parameters

nearestK	- unused
start
goal
geometricSolution	- the resulting path

Returns

Definition at line 194 of file SPARSdb.cpp.

lazyCollisionSearch()

bool ompl::geometric::SPARSdb::lazyCollisionSearch ( const Vertex &  start, const Vertex &  goal, const base::State *  actualStart, const base::State *  actualGoal, CandidateSolution &  candidateSolution, const base::PlannerTerminationCondition &  ptc  )

protected

Repeatidly search through graph for connection then check for collisions then repeat.

Returns

true if a valid path is found

Definition at line 308 of file SPARSdb.cpp.

setPlannerData()

void ompl::geometric::SPARSdb::setPlannerData

(

const base::PlannerData &

data

)

Set the sparse graph from file.

Parameters

a	pre-built graph

Definition at line 1770 of file SPARSdb.cpp.

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

• ompl/tools/thunder/SPARSdb.h
• ompl/tools/thunder/src/SPARSdb.cpp