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IN NO EVENT SHALL THE 25 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 29 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 31 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 32 * POSSIBILITY OF SUCH DAMAGE. 33 *********************************************************************/ 34 35 /* Author: Ioan Sucan */ 36 37 #ifndef OMPL_CONTROL_SIMPLE_DIRECTED_CONTROL_SAMPLER_ 38 #define OMPL_CONTROL_SIMPLE_DIRECTED_CONTROL_SAMPLER_ 39 40 #include "ompl/control/DirectedControlSampler.h" 41 #include "ompl/control/ControlSampler.h" 42 43 namespace ompl 44 { 45 namespace control 46 { 47 /** \brief Implementation of a simple directed control 48 sampler. This is a basic implementation that does not 49 actually take direction into account and builds upon ControlSampler. 50 Instead, a set of k random controls are sampled, and the control that 51 gets the system closest to the target state is returned. 52 53 @par External documentation 54 K-control sampling is first believed to be proposed in: 55 56 S.M. LaValle and J.J. Kuffner, Randomized kinodynamic planning, <em>Intl. J. of Robotics Research</em>, vol. 57 20, pp. 378–400, May 2001. DOI: [10.1177/02783640122067453](http://dx.doi.org/10.1177/02783640122067453)<br> 58 [[PDF]](http://ijr.sagepub.com/content/20/5/378.full.pdf) 59 [[more]](http://msl.cs.uiuc.edu/~lavalle/rrtpubs.html) */ 60 class SimpleDirectedControlSampler : public DirectedControlSampler 61 { 62 public: 63 /** \brief Constructor takes the state space to construct samples for as argument 64 Optionally, a \e k value can be given to indicate the number of controls to 65 try when directing a system toward a specific state. Default value is 1. */ 66 SimpleDirectedControlSampler(const SpaceInformation *si, unsigned int k = 1); 67 68 ~SimpleDirectedControlSampler() override; 69 70 /** \brief Retrieve the number of controls to generate when finding the best control. */ getNumControlSamples()71 unsigned int getNumControlSamples() const 72 { 73 return numControlSamples_; 74 } 75 76 /** \brief Set the number of controls to generate when finding the best control. */ setNumControlSamples(unsigned int numSamples)77 void setNumControlSamples(unsigned int numSamples) 78 { 79 numControlSamples_ = numSamples; 80 } 81 82 /** \brief Sample a control given that it will be applied 83 to state \e state and the intention is to reach state 84 \e dest. This is useful for some algorithms that 85 have a notion of direction in their exploration (e.g., 86 \ref cRRT). Furthermore, return the duration for which 87 this control should be applied. The state 88 \e dest is modified to match the state reached with the computed 89 control and duration. The motion is checked for validity. */ 90 unsigned int sampleTo(Control *control, const base::State *source, base::State *dest) override; 91 92 /** \brief Sample a control given that it will be applied 93 to state \e state and the intention is to reach state 94 \e dest. Also take into account the fact that the 95 previously applied control is \e previous. This is 96 useful for some algorithms that have a notion of 97 direction in their exploration (e.g., 98 \ref cRRT). Furthermore, return the duration for which 99 this control should be applied. The state \e dest is 100 modified to match the state reached with the computed 101 control and duration. The motion is checked for validity. */ 102 unsigned int sampleTo(Control *control, const Control *previous, const base::State *source, 103 base::State *dest) override; 104 105 protected: 106 /** \brief Samples \e numControlSamples_ controls, and returns the 107 control that brings the system the closest to \e target */ 108 virtual unsigned int getBestControl(Control *control, const base::State *source, base::State *dest, 109 const Control *previous); 110 111 /** \brief An instance of the control sampler*/ 112 ControlSamplerPtr cs_; 113 114 /** \brief The number of controls to sample when finding the best control*/ 115 unsigned int numControlSamples_; 116 }; 117 } 118 } 119 120 #endif 121