ompl::geometric::KPIECE1 Class Reference
Kinematic Planning by Interior-Exterior Cell Exploration. More...
#include <ompl/geometric/planners/kpiece/KPIECE1.h>
Inheritance diagram for ompl::geometric::KPIECE1:

Classes | |
class | Motion |
Representation of a motion for this algorithm. More... | |
Public Member Functions | |
KPIECE1 (const base::SpaceInformationPtr &si) | |
Constructor. | |
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. 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). The function terminates if the call to ptc returns true. | |
virtual void | clear () |
Clear all internal datastructures. Planner settings are not affected. Subsequent calls to solve() will ignore all previous work. | |
void | setGoalBias (double goalBias) |
Set the goal bias. | |
double | getGoalBias () const |
Get the goal bias the planner is using. | |
void | setRange (double distance) |
Set the range the planner is supposed to use. | |
double | getRange () const |
Get the range the planner is using. | |
void | setBorderFraction (double bp) |
Set the fraction of time for focusing on the border (between 0 and 1). This is the minimum fraction used to select cells that are exterior (minimum because if 95% of cells are on the border, they will be selected with 95% chance, even if this fraction is set to 90%) | |
double | getBorderFraction () const |
Get the fraction of time to focus exploration on boundary. | |
void | setMinValidPathFraction (double fraction) |
When extending a motion, the planner can decide to keep the first valid part of it, even if invalid states are found, as long as the valid part represents a sufficiently large fraction from the original motion. This function sets the minimum acceptable fraction (between 0 and 1). | |
double | getMinValidPathFraction () const |
Get the value of the fraction set by setMinValidPathFraction() | |
void | setFailedExpansionCellScoreFactor (double factor) |
When extending a motion from a cell, the extension can be successful or it can fail. If the extension fails, the score of the cell is multiplied by factor. These number should be in the range (0, 1]. | |
double | getFailedExpansionCellScoreFactor () const |
Get the factor that is multiplied to a cell's score if extending a motion from that cell failed. | |
void | setProjectionEvaluator (const base::ProjectionEvaluatorPtr &projectionEvaluator) |
Set the projection evaluator. This class is able to compute the projection of a given state. | |
void | setProjectionEvaluator (const std::string &name) |
Set the projection evaluator (select one from the ones registered with the state space). | |
const base::ProjectionEvaluatorPtr & | getProjectionEvaluator () const |
Get the projection evaluator. | |
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. | |
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). | |
Protected Member Functions | |
void | freeMotion (Motion *motion) |
Free the memory for a motion. | |
Protected Attributes | |
base::StateSamplerPtr | sampler_ |
A state space sampler. | |
Discretization< Motion > | disc_ |
The tree datastructure and the grid that covers it. | |
base::ProjectionEvaluatorPtr | projectionEvaluator_ |
This algorithm uses a discretization (a grid) to guide the exploration. The exploration is imposed on a projection of the state space. | |
double | failedExpansionScoreFactor_ |
When extending a motion from a cell, the extension can fail. If it is, the score of the cell is multiplied by this factor. | |
double | goalBias_ |
The fraction of time the goal is picked as the state to expand towards (if such a state is available) | |
double | minValidPathFraction_ |
When extending a motion, the planner can decide to keep the first valid part of it, even if invalid states are found, as long as the valid part represents a sufficiently large fraction from the original motion. | |
double | maxDistance_ |
The maximum length of a motion to be added to a tree. | |
RNG | rng_ |
The random number generator. | |
Motion * | lastGoalMotion_ |
The most recent goal motion. Used for PlannerData computation. |
Detailed Description
Kinematic Planning by Interior-Exterior Cell Exploration.
- Short description
- KPIECE is a tree-based planner that uses a discretization (multiple levels, in general) to guide the exploration of the continuous space. This implementation is a simplified one, using a single level of discretization: one grid. The grid is imposed on a projection of the state space. When exploring the space, preference is given to the boundary of this grid. The boundary is computed to be the set of grid cells that have less than 2n non-diagonal neighbors in an n-dimensional projection space. It is important to set the projection the algorithm uses (setProjectionEvaluator() function). If no projection is set, the planner will attempt to use the default projection associated to the state space. An exception is thrown if no default projection is available either.
- External documentation
- I.A. Şucan and L.E. Kavraki, Kinodynamic motion planning by interior-exterior cell exploration, in Workshop on the Algorithmic Foundations of Robotics, Dec. 2008.
[[PDF]](http://ioan.sucan.ro/files/pubs/wafr2008.pdf)
Member Function Documentation
void ompl::geometric::KPIECE1::setGoalBias | ( | double | goalBias | ) | [inline] |
Set the goal bias.
In the process of randomly selecting states in the state space to attempt to go towards, the algorithm may in fact choose the actual goal state, if it knows it, with some probability. This probability is a real number between 0.0 and 1.0; its value should usually be around 0.05 and should not be too large. It is probably a good idea to use the default value.
void ompl::geometric::KPIECE1::setRange | ( | double | distance | ) | [inline] |
The documentation for this class was generated from the following files:
- ompl/geometric/planners/kpiece/KPIECE1.h
- ompl/geometric/planners/kpiece/src/KPIECE1.cpp