/// 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))); }
/// 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)); }
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++; } } }
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++; } } }