ompl::geometric::SPARStwo Class Reference

SPArse Roadmap Spanner Version 2.0 More...

#include <ompl/geometric/planners/prm/SPARStwo.h>

Inheritance diagram for ompl::geometric::SPARStwo:


struct  InterfaceData
 Interface information storage class, which does bookkeeping for criterion four. More...
struct  vertex_color_t
struct  vertex_interface_data_t
struct  vertex_state_t

Public Types

enum  GuardType {
 Enumeration which specifies the reason a guard is added to the spanner.
typedef unsigned long int VertexIndexType
 The type used internally for representing vertex IDs.
typedef std::pair< VertexIndexType, VertexIndexTypeVertexPair
 Pair of vertices which support an interface.
typedef std::unordered_map< VertexPair, InterfaceDataInterfaceHash
 the hash which maps pairs of neighbor points to pairs of states
typedef boost::adjacency_list< boost::vecS, boost::vecS, boost::undirectedS, 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, InterfaceHash > > > > >, boost::property< boost::edge_weight_t, base::Cost > > Graph
 The underlying roadmap graph. More...
typedef boost::graph_traits< Graph >::vertex_descriptor Vertex
 Vertex in Graph.
typedef boost::graph_traits< Graph >::edge_descriptor Edge
 Edge in Graph.
- Public Types inherited from ompl::base::Planner
typedef std::function< std::string()> PlannerProgressProperty
 Definition of a function which returns a property about the planner's progress that can be queried by a benchmarking routine.
typedef std::map< std::string, PlannerProgressPropertyPlannerProgressProperties
 A dictionary which maps the name of a progress property to the function to be used for querying that property.

Public Member Functions

 SPARStwo (const base::SpaceInformationPtr &si)
virtual ~SPARStwo ()
virtual void setProblemDefinition (const base::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().
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.
void constructRoadmap (const base::PlannerTerminationCondition &ptc)
 While the termination condition permits, construct the spanner graph.
void constructRoadmap (const base::PlannerTerminationCondition &ptc, bool stopOnMaxFail)
 While the termination condition permits, construct the spanner graph. If stopOnMaxFail is true, the function also terminates when the failure limit set by setMaxFailures() is reached.
virtual base::PlannerStatus solve (const base::PlannerTerminationCondition &ptc)
 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 ()
 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.
virtual void clear ()
 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.
virtual void setup ()
 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 GraphgetRoadmap () const
 Retrieve the computed roadmap.
unsigned int milestoneCount () const
 Get the number of vertices in the sparse roadmap.
virtual void getPlannerData (base::PlannerData &data) const
 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 printDebug (std::ostream &out=std::cout) const
 Print debug information about planner.
std::string getIterationCount () const
std::string getBestCost () const
- Public Member Functions inherited from ompl::base::Planner
 Planner (const Planner &)=delete
Planneroperator= (const Planner &)=delete
 Planner (const SpaceInformationPtr &si, const std::string &name)
virtual ~Planner ()
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 SpaceInformationPtrgetSpaceInformation () const
 Get the space information this planner is using.
const ProblemDefinitionPtrgetProblemDefinition () const
 Get the problem definition the planner is trying to solve.
const PlannerInputStatesgetPlannerInputStates () const
 Get the planner input states.
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 PlannerSpecsgetSpecs () 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.
ParamSetparams ()
 Get the parameters for this planner.
const ParamSetparams () const
 Get the parameters for this planner.
const PlannerProgressPropertiesgetPlannerProgressProperties () 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 *st, std::vector< Vertex > &graphNeighborhood, std::vector< Vertex > &visibleNeighborhood)
 Finds visible nodes in the graph near st.
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 *workArea, 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.
InterfaceDatagetData (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 haveSolution (const std::vector< Vertex > &start, const std::vector< Vertex > &goal, base::PathPtr &solution)
 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.
void checkForSolution (const base::PlannerTerminationCondition &ptc, base::PathPtr &solution)
bool reachedTerminationCriterion () const
 Returns true if we have reached the iteration failures limit, maxFailures_ or if a solution was added.
bool reachedFailureLimit () const
 Returns whether we have reached the iteration failures limit, maxFailures_.
base::PathPtr constructSolution (const Vertex start, const Vertex goal) const
 Given two milestones from the same connected component, construct a path connecting them and set it as the solution.
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)
base::Cost costHeuristic (Vertex u, Vertex v) const
 Given two vertices, returns a heuristic on the cost of the path connecting them. This method wraps OptimizationObjective::motionCostHeuristic.
- 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.
base::StateSamplerPtr simpleSampler_
 Sampler user for generating random in the state space.
std::shared_ptr< NearestNeighbors< Vertex > > nn_
 Nearest neighbors data structure.
Graph g_
 Connectivity graph.
std::vector< VertexstartM_
 Array of start milestones.
std::vector< VertexgoalM_
 Array of goal milestones.
Vertex queryVertex_
 Vertex for performing nearest neighbor queries.
double stretchFactor_
 Stretch Factor as per graph spanner literature (multiplicative bound on path quality)
double sparseDeltaFraction_
 Maximum visibility range for nodes in the graph as a fraction of maximum extent.
double denseDeltaFraction_
 Maximum range for allowing two samples to support an interface as a fraction of maximum extent.
unsigned int maxFailures_
 The number of consecutive failures to add to the graph before termination.
unsigned int nearSamplePoints_
 Number of sample points to use when trying to detect interfaces.
boost::property_map< Graph, vertex_state_t >::type stateProperty_
 Access to the internal base::state at each Vertex.
PathSimplifierPtr psimp_
 A path simplifier used to simplify dense paths added to the graph.
boost::property_map< Graph, boost::edge_weight_t >::type weightProperty_
 Access to the weights of each Edge.
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_
 A flag indicating that a solution has been added during solve()
unsigned int consecutiveFailures_
 A counter for the number of consecutive failed iterations of the algorithm.
double sparseDelta_
 Maximum visibility range for nodes in the graph.
double denseDelta_
 Maximum range for allowing two samples to support an interface.
std::mutex graphMutex_
 Mutex to guard access to the Graph member (g_)
base::OptimizationObjectivePtr opt_
 Objective cost function for PRM graph edges.
long unsigned int iterations_
 A counter for the number of iterations of the algorithm.
base::Cost bestCost_
 Best cost found so far by algorithm.
- 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
SPARStwo 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.
External documentation
A. Dobson, K. Bekris, Improving Sparse Roadmap Spanners, IEEE International Conference on Robotics and Automation (ICRA) May 2013. [PDF]

Definition at line 80 of file SPARStwo.h.

Member Typedef Documentation

typedef boost::adjacency_list< boost::vecS, boost::vecS, boost::undirectedS, 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, InterfaceHash > > > > >, boost::property < boost::edge_weight_t, base::Cost > > ompl::geometric::SPARStwo::Graph

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.
Obviously, a ompl::base::State* vertex property is required.
The incremental connected components algorithm requires vertex_predecessor_t and vertex_rank_t properties. If boost::vecS is not used for vertex storage, then there must also be a boost:vertex_index_t property manually added.
Edges should be undirected and have a weight property.

Definition at line 220 of file SPARStwo.h.

Member Function Documentation

void ompl::geometric::SPARStwo::checkForSolution ( const base::PlannerTerminationCondition ptc,
base::PathPtr solution 

Thread that checks for solution

Definition at line 371 of file SPARStwo.cpp.

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