ompl::geometric::STRRTstar Class Reference

Space-Time RRT* (STRRTstar) More...

#include <ompl/geometric/planners/rrt/STRRTstar.h>

Inheritance diagram for ompl::geometric::STRRTstar:

Classes

struct  TreeGrowingInfo
Information attached to growing a tree of motions (used internally) More...

Public Member Functions

STRRTstar (const ompl::base::SpaceInformationPtr &si)
Constructor.

void clear () override
Clear all internal datastructures. Planner settings are not affected. Subsequent calls to solve() will ignore all previous work.

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).

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. If this option is used, it is assumed the problem definition is not changed (unpredictable results otherwise). The only change in the problem definition that is accounted for is the addition of starting or goal states (but not changing previously added start/goal states). If clearQuery() is called, the planner may retain prior datastructures generated from a previous query on a new problem definition. The function terminates if the call to ptc returns true.

void setRange (double distance)
Set the range the planner is supposed to use. More...

double getRange () const
Get the range the planner is using.

double getOptimumApproxFactor () const
The Optimum Approximation factor (0 - 1).

void setOptimumApproxFactor (double optimumApproxFactor)
Set the Optimum Approximation factor. This allows the planner to converge more quickly, but only yields approximately optimal solutions.

std::string getRewiringState () const

void setRewiringToOff ()
Do not rewire at all.

void setRewiringToKNearest ()
Rewire by k-nearest.

double getRewireFactor () const

void setRewireFactor (double v)

unsigned int getBatchSize () const
The number of samples before the time bound is increased.

void setBatchSize (int v)

void setTimeBoundFactorIncrease (double f)
The value by which the time bound factor is multiplied in each increase step.

void setInitialTimeBoundFactor (double f)
The initial time bound factor.

void setSampleUniformForUnboundedTime (bool uniform)
Whether the state space is sampled uniformly or centered at lower time values.

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.

Public Member Functions inherited from ompl::base::Planner
Planner (const Planner &)=delete

Planneroperator= (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 SpaceInformationPtrgetSpaceInformation () const
Get the space information this planner is using.

const ProblemDefinitionPtrgetProblemDefinition () const
Get the problem definition the planner is trying to solve.

ProblemDefinitionPtrgetProblemDefinition ()
Get the problem definition the planner is trying to solve.

const PlannerInputStatesgetPlannerInputStates () 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.

virtual void clearQuery ()
Clears internal datastructures of any query-specific information from the previous query. Planner settings are not affected. The planner, if able, should retain all datastructures generated from previous queries that can be used to help solve the next query. Note that clear() should also clear all query-specific information along with all other datastructures in the planner. By default clearQuery() calls clear().

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 Types

enum  GrowState { TRAPPED, ADVANCED, REACHED }
The state of the tree after an attempt to extend it. More...

enum  RewireState { RADIUS, KNEAREST, OFF }

using TreeData = std::shared_ptr< ompl::NearestNeighbors< base::Motion * > >
A nearest-neighbor datastructure representing a tree of motions.

Protected Member Functions

GrowState growTreeSingle (TreeData &tree, TreeGrowingInfo &tgi, base::Motion *rmotion, base::Motion *nmotion)
Grow a tree towards a random state for a single nearest state.

GrowState growTree (TreeData &tree, TreeGrowingInfo &tgi, base::Motion *rmotion, std::vector< base::Motion * > &nbh, bool connect)
Attempt to grow a tree towards a random state for the neighborhood of the random state. The neighborhood is determined by the used rewire state. For the start tree closest state with respect to distance are tried first. For the goal tree states with the minimum time root node are tried first. If connect is true, multiple vertices can be added to the tree until the random state is reached or an basestacle is met. If connect is false, the tree is only extended by a single new state.

void increaseTimeBound (bool hasEqualBounds, double &oldBatchTimeBoundFactor, double &newBatchTimeBoundFactor, bool &startTree, unsigned int &batchSize, int &numBatchSamples)

void getNeighbors (TreeData &tree, base::Motion *motion, std::vector< base::Motion * > &nbh) const
Gets the neighbours of a given motion, using either k-nearest or radius_ as appropriate.

void freeMemory ()
Free the memory allocated by this planner.

double distanceFunction (const base::Motion *a, const base::Motion *b) const
Compute distance between motions (actually distance between contained states)

void pruneStartTree ()
Prune the start tree after a solution was found.

base::MotionpruneGoalTree ()
Prune the goal tree after a solution was found. Return the goal motion, that is connected to the start tree, if a new solution was found. If no new solution was found, return nullpointer.

void removeInvalidGoals (const std::vector< base::Motion * > &invalidGoals)
Remove invalid goal states from the goal set.

base::StatenextGoal (int n, double oldBatchTimeBoundFactor, double newBatchTimeBoundFactor)
N tries to sample a goal.

base::StatenextGoal (const base::PlannerTerminationCondition &ptc, double oldBatchTimeBoundFactor, double newBatchTimeBoundFactor)
Samples a goal until successful or the termination condition is fulfilled.

base::StatenextGoal (const base::PlannerTerminationCondition &ptc, int n, double oldBatchTimeBoundFactor, double newBatchTimeBoundFactor)
Samples a goal until successful or the termination condition is fulfilled.

bool sampleGoalTime (base::State *goal, double oldBatchTimeBoundFactor, double newBatchTimeBoundFactor)
Samples the time component of a goal state dependant on its space component. Returns false, if goal can't be reached in time.

void constructSolution (base::Motion *startMotion, base::Motion *goalMotion, const base::ReportIntermediateSolutionFn &intermediateSolutionCallback, const ompl::base::PlannerTerminationCondition &ptc)

void calculateRewiringLowerBounds ()
Calculate the k_RRG* and r_RRG* terms.

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.

Static Protected Member Functions

static base::MotioncomputeSolutionMotion (base::Motion *motion)
Find the solution (connecting) motion for a motion that is indirectly connected.

static void removeFromParent (base::Motion *m)
Removes the given motion from the parent's child list.

static void addDescendants (base::Motion *m, const TreeData &tree)
Adds given all descendants of the given motion to given tree and checks whether one of the added motions is the goal motion. More...

Protected Attributes

base::ConditionalStateSampler sampler_
State sampler.

TreeData tStart_
The start tree.

TreeData tGoal_
The goal tree.

double maxDistance_ {0.}
The maximum length of a motion to be added to a tree.

double distanceBetweenTrees_
Distance between the nearest pair of start tree and goal tree nodes.

base::PathPtr bestSolution_ {nullptr}
The current best solution path with respect to shortest time.

double bestTime_ = std::numeric_limits<double>::infinity()
The current best time i.e. cost of all found solutions.

unsigned int numIterations_ = 0
The number of while loop iterations.

int numSolutions_ = 0
The number of found solutions.

double minimumTime_ = std::numeric_limits<double>::infinity()
Minimum Time at which any goal can be reached, if moving on a straight line.

double upperTimeBound_
Upper bound for the time up to which solutions are searched for.

double optimumApproxFactor_ = 1.0
The factor to which found solution times need to be reduced compared to minimum time, (0, 1].

base::MotionstartMotion_ {nullptr}
The start Motion, used for conditional sampling and start tree pruning.

std::vector< base::Motion * > goalMotions_ {}
The goal Motions, used for conditional sampling and pruning.

std::vector< base::Motion * > newBatchGoalMotions_ {}
The goal Motions, that were added in the current expansion step, used for uniform sampling over a growing region.

base::StatetempState_ {nullptr}

RewireState rewireState_ = KNEAREST

double rewireFactor_ {1.1}
The rewiring factor, s, so that r_rrt = s \times r_rrt* > r_rrt* (or k_rrt = s \times k_rrt* > k_rrt*)

double k_rrt_ {0u}
A constant for k-nearest rewiring calculations.

double r_rrt_ {0.}
A constant for r-disc rewiring calculations.

bool isTimeBounded_
Whether the time is bounded or not. The first solution automatically bounds the time.

double initialTimeBound_
The time bound the planner is initialized with. Used to reset for repeated planning.

unsigned int initialBatchSize_ = 512
Number of samples of the first batch.

double initialTimeBoundFactor_ = 2.0
Initial factor, the minimum time of each goal is multiplied with to calculate the upper time bound.

double timeBoundFactorIncrease_ = 2.0
The factor, the time bound is increased with after the batch is full.

bool sampleOldBatch_ = true

bool sampleUniformForUnboundedTime_ = true
Whether the samples are uniformly distributed over the whole space or are centered at lower times.

int goalStateSampleRatio_ = 4
The ratio, a goal state is sampled compared to the size of the goal tree.

ompl::RNG rng_
The random number generator.

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.

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.

Detailed Description

Space-Time RRT* (STRRTstar)

Short description
ST-RRT* is a bidirectional, time-optimal planner for planning in space-time. It operates similar to a bidirectional version of RRT*, but allows planning in unbounded time spaces by gradual time-bound extensions and is highly optimized for planning in space-time by employing Conditional Sampling and Simplified Rewiring.

Definition at line 129 of file STRRTstar.h.

◆ GrowState

 protected

The state of the tree after an attempt to extend it.

Enumerator
TRAPPED

progress has been made towards the randomly sampled state

REACHED

the randomly sampled state was reached

Definition at line 237 of file STRRTstar.h.

Member Function Documentation

 void ompl::geometric::STRRTstar::addDescendants ( base::Motion * m, const TreeData & tree )
staticprotected

Adds given all descendants of the given motion to given tree and checks whether one of the added motions is the goal motion.

Adds all descendants of a motion to a given tree.

Parameters
 m The motion, which descendants are added tree The tree that the motions are added to

Definition at line 954 of file STRRTstar.cpp.

◆ setRange()

 void ompl::geometric::STRRTstar::setRange ( double distance )

Set the range the planner is supposed to use.

    This parameter greatly influences the runtime of the
algorithm. It represents the maximum length of a
motion to be added in the tree of motions.


Definition at line 1134 of file STRRTstar.cpp.

◆ tempState_

 base::State* ompl::geometric::STRRTstar::tempState_ {nullptr}
protected

Goal Sampling is not handled by PlannerInputStates, but directly by the SpaceTimeRRT, because the time component of every goal sample is sampled dependent on the sampled space component.

Definition at line 340 of file STRRTstar.h.

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