SE_traits.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 "base-precomp.h"  // Precompiled headers

#include <mrpt/poses/SE_traits.h>

using namespace mrpt;
using namespace mrpt::math;
using namespace mrpt::utils;
using namespace mrpt::poses;

/** A pseudo-Logarithm map in SE(3), where the output = [X,Y,Z, Ln(ROT)], that is, the normal
  *  SO(3) logarithm is used for the rotation components, but the translation is left unmodified.
  */
void SE_traits<3>::pseudo_ln(const CPose3D &P, array_t &x)
{
        x[0] = P.m_coords[0];
        x[1] = P.m_coords[1];
        x[2] = P.m_coords[2];
        CArrayDouble<3> ln_rot = P.ln_rotation();
        x[3] = ln_rot[0];
        x[4] = ln_rot[1];
        x[5] = ln_rot[2];
}


/** Return one or both of the following 6x6 Jacobians, useful in graph-slam problems...
  */
void SE_traits<3>::jacobian_dP1DP2inv_depsilon(
        const CPose3D &P1DP2inv,
        matrix_VxV_t *df_de1,
        matrix_VxV_t *df_de2)
{
        const CMatrixDouble33 & R = P1DP2inv.getRotationMatrix(); // The rotation matrix.

        // Common part: d_Ln(R)_dR:
        CMatrixFixedNumeric<double,3,9> dLnRot_dRot(UNINITIALIZED_MATRIX);
        CPose3D::ln_rot_jacob(R, dLnRot_dRot);

        if (df_de1)
        {
                matrix_VxV_t & J1 = *df_de1;
                // This Jacobian has the structure:
                //           [   I_3    |      -[d_t]_x      ]
                //  Jacob1 = [ ---------+------------------- ]
                //           [   0_3x3  |   dLnR_dR * (...)  ]
                //
                J1.zeros();
                J1(0,0) = 1;
                J1(1,1) = 1;
                J1(2,2) = 1;

                                                                  J1(0,4) = P1DP2inv.z();  J1(0,5) = -P1DP2inv.y();
                J1(1,3) = -P1DP2inv.z();                           J1(1,5) =  P1DP2inv.x();
                J1(2,3) =  P1DP2inv.y();  J1(2,4) =-P1DP2inv.x();

                MRPT_ALIGN16 const double aux_vals[] = {
                                  0,  R(2,0), -R(1,0),
                        -R(2,0),       0,  R(0,0),
                         R(1,0), -R(0,0),       0,
                         // -----------------------
                                  0,  R(2,1), -R(1,1),
                        -R(2,1),       0,  R(0,1),
                         R(1,1), -R(0,1),       0,
                         // -----------------------
                                  0,  R(2,2), -R(1,2),
                        -R(2,2),       0,  R(0,2),
                         R(1,2), -R(0,2),       0
                };
                const CMatrixFixedNumeric<double,9,3> aux(aux_vals);

                // right-bottom part = dLnRot_dRot * aux
                J1.block(3,3,3,3) = (dLnRot_dRot * aux).eval();
        }
        if (df_de2)
        {
                // This Jacobian has the structure:
                //           [    -R    |      0_3x3         ]
                //  Jacob2 = [ ---------+------------------- ]
                //           [   0_3x3  |   dLnR_dR * (...)  ]
                //
                matrix_VxV_t & J2 = *df_de2;
                J2.zeros();

                for (int i=0;i<3;i++)
                        for (int j=0;j<3;j++)
                                J2.set_unsafe(i,j, -R.get_unsafe(i,j));

                MRPT_ALIGN16 const double aux_vals[] = {
                                  0,  R(0,2), -R(0,1),
                                  0,  R(1,2), -R(1,1),
                                  0,  R(2,2), -R(2,1),
                         // -----------------------
                        -R(0,2),       0,  R(0,0),
                        -R(1,2),       0,  R(1,0),
                        -R(2,2),       0,  R(2,0),
                         // -----------------------
                         R(0,1), -R(0,0),       0,
                         R(1,1), -R(1,0),       0,
                         R(2,1), -R(2,0),       0
                };
                const CMatrixFixedNumeric<double,9,3> aux(aux_vals);

                // right-bottom part = dLnRot_dRot * aux
                J2.block(3,3,3,3) = (dLnRot_dRot * aux).eval();
        }
}



/** Return one or both of the following 6x6 Jacobians, useful in graph-slam problems...
  */
void SE_traits<2>::jacobian_dP1DP2inv_depsilon(
        const CPose2D &P1DP2inv,
        matrix_VxV_t *df_de1,
        matrix_VxV_t *df_de2)
{
        if (df_de1)
        {
                matrix_VxV_t & J1 = *df_de1;
                // This Jacobian has the structure:
                //           [   I_2    |  -[d_t]_x      ]
                //  Jacob1 = [ ---------+--------------- ]
                //           [   0      |   1            ]
                //
                J1.unit(VECTOR_SIZE,1.0);
                J1(0,2) = -P1DP2inv.y();
                J1(1,2) =  P1DP2inv.x();
        }
        if (df_de2)
        {
                // This Jacobian has the structure:
                //           [    -R    |    0   ]
                //  Jacob2 = [ ---------+------- ]
                //           [     0    |    -1  ]
                //
                matrix_VxV_t & J2 = *df_de2;

                const double ccos = cos(P1DP2inv.phi());
                const double csin = sin(P1DP2inv.phi());

                const double vals[] =  {
                        -ccos, csin, 0,
                        -csin,-ccos, 0,
                            0,    0, -1
                };
                J2 = CMatrixFixedNumeric<double,3,3>(vals);
        }
}