Exemple #1
0
        /// Given the position of a point in parent frame coords, and
        /// assuming it has an absolute speed parentspeed,
        /// return the speed in local coords.
        public ChVector PointSpeedParentToLocal(ChVector parentpos, ChVector parentspeed)
        {
            ChFrame <Real> f        = new ChFrame <Real>();
            ChVector       localpos = f.TransformParentToLocal(parentpos);

            return(this.Amatrix.MatrT_x_Vect(
                       parentspeed - coord_dt.pos -
                       ((coord_dt.rot % new ChQuaternion(0, localpos) % this.coord.rot.GetConjugate()).GetVector() * 2)));
        }
Exemple #2
0
        /// Given the position of a point in parent frame coords, and
        /// assuming it has an absolute speed parentspeed and absolute
        /// acceleration parentacc, return the acceleration in local coords.
        public ChVector PointAccelerationParentToLocal(ChVector parentpos,
                                                       ChVector parentspeed,
                                                       ChVector parentacc)
        {
            ChFrame <Real> f          = this;// new ChFrame<Real>();
            ChVector       localpos   = f.TransformParentToLocal(parentpos);
            ChVector       localspeed = PointSpeedParentToLocal(parentpos, parentspeed);

            return(this.Amatrix.MatrT_x_Vect(
                       parentacc - coord_dtdt.pos -
                       (coord_dtdt.rot % new ChQuaternion(0, localpos) % this.coord.rot.GetConjugate()).GetVector() * 2 -
                       (coord_dt.rot % new ChQuaternion(0, localpos) % coord_dt.rot.GetConjugate()).GetVector() * 2 -
                       (coord_dt.rot % new ChQuaternion(0, localspeed) % this.coord.rot.GetConjugate()).GetVector() * 4));
        }
Exemple #3
0
        public override void update(double mytime, bool update_assets)
        {
            // Inherit parent class:
            base.update(mytime, update_assets);

            // Override the rotational jacobian [Cq] and the rotational residual C,
            // by assuming an additional hidden frame that rotates about frame2:

            if (this.Body1 != null && this.Body2 != null)
            {
                ChFrame <double> aframe1 = ChFrame <double> .BitShiftRight(this.frame1, (this.Body1));

                ChFrame <double> aframe2 = ChFrame <double> .BitShiftRight(this.frame2, (this.Body2));

                ChFrame <double> aframe12 = new ChFrame <double>();
                aframe2.TransformParentToLocal(aframe1, aframe12);

                ChFrame <double> aframe2rotating = new ChFrame <double>();

                double aux_rotation;

                if (this.avoid_angle_drift)
                {
                    aux_rotation = this.aux_dt + this.rot_offset;
                }
                else
                {
                    // to have it aligned to current rot, to allow C=0.
                    aux_rotation = aframe12.GetRot().Q_to_Rotv().z;
                }

                aframe2rotating.SetRot(aframe2.GetRot() * ChQuaternion.Q_from_AngAxis2(aux_rotation, ChVector.VECT_Z));

                // TODO this needs to be addressed, with it it causes rotation problems, seems to work fine without the TransformParentToLocal?
                ChFrame <double> aframe12rotating = new ChFrame <double>();
                // aframe2rotating.TransformParentToLocal(aframe1, aframe12rotating);

                ChMatrix33 <double> Jw1    = new ChMatrix33 <double>();
                ChMatrix33 <double> Jw2    = new ChMatrix33 <double>();
                ChMatrix33 <double> mtempM = new ChMatrix33 <double>();
                ChMatrix33 <double> mtempQ = new ChMatrix33 <double>();

                ChMatrix33 <double> abs_plane_rotating = aframe2rotating.GetA();

                Jw1.nm.matrix.MatrTMultiply(abs_plane_rotating.nm.matrix, Body1.GetA().nm.matrix);
                Jw2.nm.matrix.MatrTMultiply(abs_plane_rotating.nm.matrix, Body2.GetA().nm.matrix);

                Jw2.nm.matrix.MatrNeg();

                // TODO this also needs to be addressed, with it it causes rotation problems/

                // Premultiply by Jw1 and Jw2 by  0.5*[Fp(q_resid)]' to get residual as imaginary part of a quaternion.

                /* mtempM.Set_X_matrix((aframe12rotating.GetRot().GetVector()) * 0.5);
                 * mtempM[0, 0] = 0.5 * aframe12rotating.GetRot().e0;
                 * mtempM[1, 1] = 0.5 * aframe12rotating.GetRot().e0;
                 * mtempM[2, 2] = 0.5 * aframe12rotating.GetRot().e0;
                 * mtempQ.MatrTMultiply(mtempM, Jw1);
                 * Jw1 = mtempQ;
                 * mtempQ.MatrTMultiply(mtempM, Jw2);
                 * Jw2 = mtempQ;*/

                int nc = 0;

                if (c_x)
                {
                    nc++;
                }
                if (c_y)
                {
                    nc++;
                }
                if (c_z)
                {
                    nc++;
                }
                if (c_rx)
                {
                    this.C.matrix.ElementN(nc) = aframe12rotating.GetRot().e1;
                    this.mask.Constr_N(nc).Get_Cq_a().FillElem(0);
                    this.mask.Constr_N(nc).Get_Cq_b().FillElem(0);
                    this.mask.Constr_N(nc).Get_Cq_a().PasteClippedMatrix(Jw1.nm.matrix, 0, 0, 1, 3, 0, 3);
                    this.mask.Constr_N(nc).Get_Cq_b().PasteClippedMatrix(Jw2.nm.matrix, 0, 0, 1, 3, 0, 3);
                    nc++;
                }
                if (c_ry)
                {
                    this.C.matrix.ElementN(nc) = aframe12rotating.GetRot().e2;
                    this.mask.Constr_N(nc).Get_Cq_a().FillElem(0);
                    this.mask.Constr_N(nc).Get_Cq_b().FillElem(0);
                    this.mask.Constr_N(nc).Get_Cq_a().PasteClippedMatrix(Jw1.nm.matrix, 1, 0, 1, 3, 0, 3);
                    this.mask.Constr_N(nc).Get_Cq_b().PasteClippedMatrix(Jw2.nm.matrix, 1, 0, 1, 3, 0, 3);
                    nc++;
                }
                if (c_rz)
                {
                    this.C.matrix.ElementN(nc) = aframe12rotating.GetRot().e3;
                    this.mask.Constr_N(nc).Get_Cq_a().FillElem(0);
                    this.mask.Constr_N(nc).Get_Cq_b().FillElem(0);
                    this.mask.Constr_N(nc).Get_Cq_a().PasteClippedMatrix(Jw1.nm.matrix, 2, 0, 1, 3, 0, 3);
                    this.mask.Constr_N(nc).Get_Cq_b().PasteClippedMatrix(Jw2.nm.matrix, 2, 0, 1, 3, 0, 3);
                    nc++;
                }
            }
        }
Exemple #4
0
        public override void update(double mytime, bool update_assets)
        {
            // Inherit parent class:
            base.update(mytime, update_assets);

            // Override the rotational jacobian [Cq] and the rotational residual C,
            // by assuming an additional hidden frame that rotates about frame2:

            if (this.Body1 != null && this.Body2 != null)
            {
                ChFrame <double> aframe1 = this.frame1.BitShiftRight(this.Body1);
                ChFrame <double> aframe2 = this.frame2.BitShiftRight(this.Body2);

                ChFrame <double> aframe12 = new ChFrame <double>();// ChFrame<double>.FNULL;
                aframe2.TransformParentToLocal(aframe1, aframe12);

                ChFrame <double> aframe2rotating = new ChFrame <double>();// ChFrame<double>.FNULL;

                double aux_rotation;

                aux_rotation = m_func.Get_y(mytime) + rot_offset;

                aframe2rotating.SetRot(aframe2.GetRot() * ChQuaternion.Q_from_AngAxis2(aux_rotation, ChVector.VECT_Z));

                ChFrame <double> aframe12rotating = new ChFrame <double>();
                // aframe2rotating.TransformParentToLocal(aframe1, aframe12rotating);

                ChMatrix33 <double> Jw1 = new ChMatrix33 <double>(0), Jw2 = new ChMatrix33 <double>(0);
                ChMatrix33 <double> mtempM = new ChMatrix33 <double>(0), mtempQ = new ChMatrix33 <double>(0);

                ChMatrix33 <double> abs_plane_rotating = aframe2rotating.GetA();

                Jw1.nm.matrix.MatrTMultiply(abs_plane_rotating.nm.matrix, Body1.GetA().nm.matrix);
                Jw2.nm.matrix.MatrTMultiply(abs_plane_rotating.nm.matrix, Body2.GetA().nm.matrix);

                Jw2.nm.matrix.MatrNeg();

                // Premultiply by Jw1 and Jw2 by  0.5*[Fp(q_resid)]' to get residual as imaginary part of a quaternion.

                /*  mtempM.Set_X_matrix((aframe12rotating.GetRot().GetVector()) * 0.5);
                 * mtempM.nm.matrix[0, 0] = 0.5 * aframe12rotating.GetRot().e0;
                 * mtempM.nm.matrix[1, 1] = 0.5 * aframe12rotating.GetRot().e0;
                 * mtempM.nm.matrix[2, 2] = 0.5 * aframe12rotating.GetRot().e0;
                 * mtempQ.nm.matrix.MatrTMultiply(mtempM.nm.matrix, Jw1.nm.matrix);
                 * Jw1 = mtempQ;
                 * mtempQ.nm.matrix.MatrTMultiply(mtempM.nm.matrix, Jw2.nm.matrix);
                 * Jw2 = mtempQ;*/

                int nc = 0;

                if (c_x)
                {
                    nc++;
                }
                if (c_y)
                {
                    nc++;
                }
                if (c_z)
                {
                    nc++;
                }
                if (c_rx)
                {
                    this.C.matrix.ElementN(nc) = aframe12rotating.GetRot().e1;
                    this.mask.Constr_N(nc).Get_Cq_a().FillElem(0);
                    this.mask.Constr_N(nc).Get_Cq_b().FillElem(0);
                    this.mask.Constr_N(nc).Get_Cq_a().PasteClippedMatrix(Jw1.nm.matrix, 0, 0, 1, 3, 0, 3);
                    this.mask.Constr_N(nc).Get_Cq_b().PasteClippedMatrix(Jw2.nm.matrix, 0, 0, 1, 3, 0, 3);
                    nc++;
                }
                if (c_ry)
                {
                    this.C.matrix.ElementN(nc) = aframe12rotating.GetRot().e2;
                    this.mask.Constr_N(nc).Get_Cq_a().FillElem(0);
                    this.mask.Constr_N(nc).Get_Cq_b().FillElem(0);
                    this.mask.Constr_N(nc).Get_Cq_a().PasteClippedMatrix(Jw1.nm.matrix, 1, 0, 1, 3, 0, 3);
                    this.mask.Constr_N(nc).Get_Cq_b().PasteClippedMatrix(Jw2.nm.matrix, 1, 0, 1, 3, 0, 3);
                    nc++;
                }
                if (c_rz)
                {
                    this.C.matrix.ElementN(nc) = aframe12rotating.GetRot().e3;
                    this.mask.Constr_N(nc).Get_Cq_a().FillElem(0);
                    this.mask.Constr_N(nc).Get_Cq_b().FillElem(0);
                    this.mask.Constr_N(nc).Get_Cq_a().PasteClippedMatrix(Jw1.nm.matrix, 2, 0, 1, 3, 0, 3);
                    this.mask.Constr_N(nc).Get_Cq_b().PasteClippedMatrix(Jw2.nm.matrix, 2, 0, 1, 3, 0, 3);
                    nc++;
                }
            }
        }