DifferentialProbabilisticMotionModel.h

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/*
 * Copyright (C) 2012 by
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 * and
 *   Neuroinformatics and Cognitive Robotics Labs (NICR) at TU Ilmenau, GERMANY
 * All rights reserved.
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#ifndef _MIRA_DIFFERENTIALPROBABILISTICMOTIONMODEL_H_
#define _MIRA_DIFFERENTIALPROBABILISTICMOTIONMODEL_H_

#include <math/Random.h>

#include <robot/ProbabilisticMotionModel.h>

namespace mira { namespace robot {


class DifferentialProbabilisticMotionModel : public ProbabilisticMotionModel
{
public:
    struct MotionParameters
    {
        MotionParameters() :
            trans(0.0f), rot1(0.0f), rot2(0.0f),
            transStddev(0.0f), rot1Stddev(0.0f), rot2Stddev(0.0f) {}

        // means
        float trans;
        float rot1;
        float rot2;

        // std.devs
        float transStddev;
        float rot1Stddev;
        float rot2Stddev;
    };

public:

    DifferentialProbabilisticMotionModel();

    template<typename Reflector>
    void reflect(Reflector& r)
    {
        r.property("AlphaRotRot", alphaRotRot,
                   "Alpha for rotation drift while rotating", 0.2f);
        r.property("AlphaRotTrans", alphaRotTrans,
                   "Alpha for translation drift while rotating", 0.2f);
        r.property("AlphaTransTrans", alphaTransTrans,
                   "Alpha for translation drift while translating", 0.2f);
        r.property("AlphaTransRot", alphaTransRot,
                   "Alpha for rotation drift while translating", 0.2f);
    }


public:

    MotionParameters calculateMotionParameters(const Pose2& p0, const Pose2& p1) const;


    virtual Pose2 sampleMotion(const Pose2& startPose, const Pose2& p0, const Pose2& p1) const;

    virtual void sampleMotion(const std::vector<Pose2>& startPoses, const Pose2& p0, const Pose2& p1,
                              std::vector<Pose2>& sampledPoses) const;

    Pose2 sampleMotion(const Pose2& startPose, const MotionParameters& parameters) const;

    PoseCov2 gaussianMotion(const PoseCov2& startPose, const MotionParameters& parameters) const;

public:

    float alphaRotRot;
    float alphaRotTrans;
    float alphaTransTrans;
    float alphaTransRot;
};


inline Pose2 DifferentialProbabilisticMotionModel::sampleMotion(const Pose2& startPose,
                                                                const MotionParameters& parameters) const
{
    float dTransSample = parameters.trans - (float)MIRA_RANDOM.normal(parameters.transStddev);
    float dRot1Sample = smallestAngleDifference(parameters.rot1,
                                                (float)MIRA_RANDOM.normal(parameters.rot1Stddev));
    float dRot2Sample = smallestAngleDifference(parameters.rot2,
                                                (float)MIRA_RANDOM.normal(parameters.rot2Stddev));

    return Pose2(startPose.x() + dTransSample * std::cos(startPose.phi() + dRot1Sample),
                 startPose.y() + dTransSample * std::sin(startPose.phi() + dRot1Sample),
                 startPose.phi() + SignedAnglef(dRot1Sample + dRot2Sample).rad());

}


}}

#endif