CPTG_DiffDrive_CC.cpp

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/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          http://www.mrpt.org/                          |
   |                                                                        |
   | Copyright (c) 2005-2017, Individual contributors, see AUTHORS file     |
   | See: http://www.mrpt.org/Authors - All rights reserved.                |
   | Released under BSD License. See details in http://www.mrpt.org/License |
   +------------------------------------------------------------------------+ */

#include "nav-precomp.h"  // Precomp header
#include <mrpt/nav/tpspace/CPTG_DiffDrive_CC.h>
#include <mrpt/system/os.h>

using namespace mrpt;
using namespace mrpt::nav;
using namespace mrpt::system;
using namespace mrpt::utils;

IMPLEMENTS_SERIALIZABLE(
        CPTG_DiffDrive_CC, CParameterizedTrajectoryGenerator, mrpt::nav)

void CPTG_DiffDrive_CC::loadFromConfigFile(
        const mrpt::utils::CConfigFileBase& cfg, const std::string& sSection)
{
        CPTG_DiffDrive_CollisionGridBased::loadFromConfigFile(cfg, sSection);

        MRPT_LOAD_CONFIG_VAR_NO_DEFAULT(K, double, cfg, sSection);

        // The constant curvature turning radius used in this PTG:
        R = V_MAX / W_MAX;
}
void CPTG_DiffDrive_CC::saveToConfigFile(
        mrpt::utils::CConfigFileBase& cfg, const std::string& sSection) const
{
        MRPT_START
        const int WN = 25, WV = 30;
        CPTG_DiffDrive_CollisionGridBased::saveToConfigFile(cfg, sSection);

        cfg.write(
                sSection, "K", K, WN, WV,
                "K=+1 forward paths; K=-1 for backwards paths.");

        MRPT_END
}

void CPTG_DiffDrive_CC::readFromStream(mrpt::utils::CStream& in, int version)
{
        CPTG_DiffDrive_CollisionGridBased::internal_readFromStream(in);

        switch (version)
        {
                case 0:
                        in >> K;
                        break;
                default:
                        MRPT_THROW_UNKNOWN_SERIALIZATION_VERSION(version)
        };
}

void CPTG_DiffDrive_CC::writeToStream(
        mrpt::utils::CStream& out, int* version) const
{
        if (version)
        {
                *version = 0;
                return;
        }

        CPTG_DiffDrive_CollisionGridBased::internal_writeToStream(out);
        out << K;
}

std::string CPTG_DiffDrive_CC::getDescription() const
{
        char str[100];
        os::sprintf(str, 100, "CPTG_DiffDrive_CC,K=%i", (int)K);
        return std::string(str);
}

void CPTG_DiffDrive_CC::ptgDiffDriveSteeringFunction(
        float alpha, float t, float x, float y, float phi, float& v, float& w) const
{
        MRPT_UNUSED_PARAM(phi);
        MRPT_UNUSED_PARAM(x);
        MRPT_UNUSED_PARAM(y);
        float u = fabs(alpha) * 0.5f;  /// 6.0f;

        if (t < u * R / V_MAX)
        {
                // l-
                v = -V_MAX;
                w = W_MAX;
        }
        else if (t < (u + M_PI * 0.5f) * R / V_MAX)
        {
                // l+
                v = V_MAX;
                w = W_MAX;
        }
        else
        {
                // END:
                v = w = 0;
        }

        // Turn in the opposite direction??
        if (alpha < 0) w *= -1;

        v *= K;
        w *= K;
}

bool CPTG_DiffDrive_CC::PTG_IsIntoDomain(double x, double y) const
{
        // Aprox domain: The circle at (0,R):
        return (square(x) + square(fabs(y) - R)) <= R;
}

void CPTG_DiffDrive_CC::loadDefaultParams()
{
        CPTG_DiffDrive_CollisionGridBased::loadDefaultParams();
        K = +1.0;
}