/// Get shaft direction, for 2nd pulley, in absolute reference
public ChVector Get_shaft_dir2()
{
if (Body1 != null)
{
ChFrame <double> absframe = ChFrame <double> .FNULL;// new ChFrame<double>();
((ChFrame <double>)Body2).TransformLocalToParent(local_shaft2, absframe);
return(absframe.GetA().Get_A_Zaxis());
}
else
{
return(ChVector.VECT_Z);
}
}
//
// SOLVER INTERFACE (OLD)
//
public override void ConstraintsFbLoadForces(double factor = 1)
{
// compute instant torque
double mT = m_func.Get_y(this.GetChTime());
ChFrame <double> aframe1 = ChFrame <double> .BitShiftRight(this.frame1, (this.Body1));
ChFrame <double> aframe2 = ChFrame <double> .BitShiftRight(this.frame2, (this.Body2));
ChVector m_abs_torque = aframe2.GetA().Matr_x_Vect(new ChVector(0, 0, mT));
Body2.Variables().Get_fb().matrix.PasteSumVector(Body2.TransformDirectionParentToLocal(m_abs_torque) * -factor, 3, 0);
Body1.Variables().Get_fb().matrix.PasteSumVector(Body1.TransformDirectionParentToLocal(m_abs_torque) * factor, 3, 0);
}
//
// STATE FUNCTIONS
//
public override void IntLoadResidual_F(int off, ref ChVectorDynamic <double> R, double c)
{
// compute instant torque
double mT = m_func.Get_y(this.GetChTime());
ChFrame <double> aframe1 = ChFrame <double> .BitShiftRight(this.frame1, (this.Body1));
ChFrame <double> aframe2 = ChFrame <double> .BitShiftRight(this.frame2, (this.Body2));
ChVector m_abs_torque = aframe2.GetA().Matr_x_Vect(new ChVector(0, 0, mT));
if (Body2.Variables().IsActive())
{
R.matrix.PasteSumVector(Body2.TransformDirectionParentToLocal(m_abs_torque) * -c, Body2.Variables().GetOffset() + 3,
0);
}
if (Body1.Variables().IsActive())
{
R.matrix.PasteSumVector(Body1.TransformDirectionParentToLocal(m_abs_torque) * c, Body1.Variables().GetOffset() + 3,
0);
}
}
/// Updates motion laws, marker positions, etc.
public override void UpdateTime(double mytime)
{
// First, inherit to parent class
base.UpdateTime(mytime);
ChFrame <double> abs_shaft1 = ChFrame <double> .FNULL; //new ChFrame<double>();
ChFrame <double> abs_shaft2 = ChFrame <double> .FNULL; //new ChFrame<double>();
((ChFrame <double>)Body1).TransformLocalToParent(local_shaft1, abs_shaft1);
((ChFrame <double>)Body2).TransformLocalToParent(local_shaft2, abs_shaft2);
ChVector dcc_w = ChVector.Vsub(Get_shaft_pos2(), Get_shaft_pos1());
// compute actual rotation of the two wheels (relative to truss).
ChVector md1 = abs_shaft1.GetA().MatrT_x_Vect(dcc_w);
md1.z = 0;
md1 = ChVector.Vnorm(md1);
ChVector md2 = abs_shaft2.GetA().MatrT_x_Vect(dcc_w);
md2.z = 0;
md2 = ChVector.Vnorm(md2);
double periodic_a1 = ChMaths.ChAtan2(md1.x, md1.y);
double periodic_a2 = ChMaths.ChAtan2(md2.x, md2.y);
double old_a1 = a1;
double old_a2 = a2;
double turns_a1 = Math.Floor(old_a1 / ChMaths.CH_C_2PI);
double turns_a2 = Math.Floor(old_a2 / ChMaths.CH_C_2PI);
double a1U = turns_a1 * ChMaths.CH_C_2PI + periodic_a1 + ChMaths.CH_C_2PI;
double a1M = turns_a1 * ChMaths.CH_C_2PI + periodic_a1;
double a1L = turns_a1 * ChMaths.CH_C_2PI + periodic_a1 - ChMaths.CH_C_2PI;
a1 = a1M;
if (Math.Abs(a1U - old_a1) < Math.Abs(a1M - old_a1))
{
a1 = a1U;
}
if (Math.Abs(a1L - a1) < Math.Abs(a1M - a1))
{
a1 = a1L;
}
double a2U = turns_a2 * ChMaths.CH_C_2PI + periodic_a2 + ChMaths.CH_C_2PI;
double a2M = turns_a2 * ChMaths.CH_C_2PI + periodic_a2;
double a2L = turns_a2 * ChMaths.CH_C_2PI + periodic_a2 - ChMaths.CH_C_2PI;
a2 = a2M;
if (Math.Abs(a2U - old_a2) < Math.Abs(a2M - old_a2))
{
a2 = a2U;
}
if (Math.Abs(a2L - a2) < Math.Abs(a2M - a2))
{
a2 = a2L;
}
// correct marker positions if phasing is not correct
double m_delta = 0;
if (checkphase)
{
double realtau = tau;
m_delta = a1 - phase - (a2 / realtau);
if (m_delta > ChMaths.CH_C_PI)
{
m_delta -= (ChMaths.CH_C_2PI); // range -180..+180 is better than 0...360
}
if (m_delta > (ChMaths.CH_C_PI / 4.0))
{
m_delta = (ChMaths.CH_C_PI / 4.0); // phase correction only in +/- 45°
}
if (m_delta < -(ChMaths.CH_C_PI / 4.0))
{
m_delta = -(ChMaths.CH_C_PI / 4.0);
}
//***TODO***
}
// Move markers 1 and 2 to align them as pulley ends
ChVector d21_w = dcc_w - Get_shaft_dir1() * ChVector.Vdot(Get_shaft_dir1(), dcc_w);
ChVector D21_w = ChVector.Vnorm(d21_w);
shaft_dist = d21_w.Length();
ChVector U1_w = ChVector.Vcross(Get_shaft_dir1(), D21_w);
double gamma1 = Math.Acos((r1 - r2) / shaft_dist);
ChVector Ru_w = D21_w * Math.Cos(gamma1) + U1_w * Math.Sin(gamma1);
ChVector Rl_w = D21_w * Math.Cos(gamma1) - U1_w * Math.Sin(gamma1);
belt_up1 = Get_shaft_pos1() + Ru_w * r1;
belt_low1 = Get_shaft_pos1() + Rl_w * r1;
belt_up2 = Get_shaft_pos1() + d21_w + Ru_w * r2;
belt_low2 = Get_shaft_pos1() + d21_w + Rl_w * r2;
// marker alignment
ChMatrix33 <double> maU = new ChMatrix33 <double>(0);
ChMatrix33 <double> maL = new ChMatrix33 <double>(0);
ChVector Dxu = ChVector.Vnorm(belt_up2 - belt_up1);
ChVector Dyu = Ru_w;
ChVector Dzu = ChVector.Vnorm(ChVector.Vcross(Dxu, Dyu));
Dyu = ChVector.Vnorm(ChVector.Vcross(Dzu, Dxu));
maU.Set_A_axis(Dxu, Dyu, Dzu);
// ! Require that the BDF routine of marker won't handle speed and acc.calculus of the moved marker 2!
marker2.SetMotionType(ChMarker.eChMarkerMotion.M_MOTION_EXTERNAL);
marker1.SetMotionType(ChMarker.eChMarkerMotion.M_MOTION_EXTERNAL);
ChCoordsys newmarkpos = new ChCoordsys();
// move marker1 in proper positions
newmarkpos.pos = this.belt_up1;
newmarkpos.rot = maU.Get_A_quaternion();
marker1.Impose_Abs_Coord(newmarkpos); // move marker1 into teeth position
// move marker2 in proper positions
newmarkpos.pos = this.belt_up2;
newmarkpos.rot = maU.Get_A_quaternion();
marker2.Impose_Abs_Coord(newmarkpos); // move marker2 into teeth position
double phase_correction_up = m_delta * r1;
double phase_correction_low = -phase_correction_up;
double hU = ChVector.Vlength(belt_up2 - belt_up1) + phase_correction_up;
double hL = ChVector.Vlength(belt_low2 - belt_low1) + phase_correction_low;
// imposed relative positions/speeds
deltaC.pos = new ChVector(-hU, 0, 0);
deltaC_dt.pos = ChVector.VNULL;
deltaC_dtdt.pos = ChVector.VNULL;
deltaC.rot = ChQuaternion.QUNIT; // no relative rotations imposed!
deltaC_dt.rot = ChQuaternion.QNULL;
deltaC_dtdt.rot = ChQuaternion.QNULL;
}
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++;
}
}
}
//
// UPDATING FUNCTIONS
//
/// Perform the update of this joint at the specified time: compute jacobians
/// and constraint violations, cache in internal structures
public override void update(double time, bool update_assets = true)
{
// Inherit time changes of parent class
base.UpdateTime(time);
// Express the joint frames in absolute frame
ChFrame <double> frame1_abs = m_frame1.BitShiftRight(Body1);
ChFrame <double> frame2_abs = m_frame2.BitShiftRight(Body2);
// Calculate violations of the spherical constraints
m_C.matrix.SetElement(0, 0, frame2_abs.coord.pos.x - frame1_abs.coord.pos.x);
m_C.matrix.SetElement(1, 0, frame2_abs.coord.pos.y - frame1_abs.coord.pos.y);
m_C.matrix.SetElement(2, 0, frame2_abs.coord.pos.z - frame1_abs.coord.pos.z);
// Compute Jacobian of the spherical constraints
// pos2_abs - pos1_abs = 0
{
ChMatrix33 <double> tilde1 = new ChMatrix33 <double>(0);
ChMatrix33 <double> tilde2 = new ChMatrix33 <double>(0);
tilde1.Set_X_matrix(m_frame1.coord.pos);
tilde2.Set_X_matrix(m_frame2.coord.pos);
ChMatrix33 <double> Phi_pi1 = Body1.GetA() * tilde1;
ChMatrix33 <double> Phi_pi2 = Body2.GetA() * tilde2;
m_cnstr_x.Get_Cq_a().ElementN(0) = -1;
m_cnstr_x.Get_Cq_b().ElementN(0) = +1;
m_cnstr_x.Get_Cq_a().ElementN(1) = 0;
m_cnstr_x.Get_Cq_b().ElementN(1) = 0;
m_cnstr_x.Get_Cq_a().ElementN(2) = 0;
m_cnstr_x.Get_Cq_b().ElementN(2) = 0;
m_cnstr_x.Get_Cq_a().ElementN(3) = Phi_pi1.nm.matrix[0, 0];
m_cnstr_x.Get_Cq_b().ElementN(3) = -Phi_pi2.nm.matrix[0, 0];
m_cnstr_x.Get_Cq_a().ElementN(4) = Phi_pi1.nm.matrix[0, 1];
m_cnstr_x.Get_Cq_b().ElementN(4) = -Phi_pi2.nm.matrix[0, 1];
m_cnstr_x.Get_Cq_a().ElementN(5) = Phi_pi1.nm.matrix[0, 2];
m_cnstr_x.Get_Cq_b().ElementN(5) = -Phi_pi2.nm.matrix[0, 2];
m_cnstr_y.Get_Cq_a().ElementN(0) = 0;
m_cnstr_y.Get_Cq_b().ElementN(0) = 0;
m_cnstr_y.Get_Cq_a().ElementN(1) = -1;
m_cnstr_y.Get_Cq_b().ElementN(1) = +1;
m_cnstr_y.Get_Cq_a().ElementN(2) = 0;
m_cnstr_y.Get_Cq_b().ElementN(2) = 0;
m_cnstr_y.Get_Cq_a().ElementN(3) = Phi_pi1.nm.matrix[1, 0];
m_cnstr_y.Get_Cq_b().ElementN(3) = -Phi_pi2.nm.matrix[1, 0];
m_cnstr_y.Get_Cq_a().ElementN(4) = Phi_pi1.nm.matrix[1, 1];
m_cnstr_y.Get_Cq_b().ElementN(4) = -Phi_pi2.nm.matrix[1, 1];
m_cnstr_y.Get_Cq_a().ElementN(5) = Phi_pi1.nm.matrix[1, 2];
m_cnstr_y.Get_Cq_b().ElementN(5) = -Phi_pi2.nm.matrix[1, 2];
m_cnstr_z.Get_Cq_a().ElementN(0) = 0;
m_cnstr_z.Get_Cq_b().ElementN(0) = 0;
m_cnstr_z.Get_Cq_a().ElementN(1) = 0;
m_cnstr_z.Get_Cq_b().ElementN(1) = 0;
m_cnstr_z.Get_Cq_a().ElementN(2) = -1;
m_cnstr_z.Get_Cq_b().ElementN(2) = +1;
m_cnstr_z.Get_Cq_a().ElementN(3) = Phi_pi1.nm.matrix[2, 0];
m_cnstr_z.Get_Cq_b().ElementN(3) = -Phi_pi2.nm.matrix[2, 0];
m_cnstr_z.Get_Cq_a().ElementN(4) = Phi_pi1.nm.matrix[2, 1];
m_cnstr_z.Get_Cq_b().ElementN(4) = -Phi_pi2.nm.matrix[2, 1];
m_cnstr_z.Get_Cq_a().ElementN(5) = Phi_pi1.nm.matrix[2, 2];
m_cnstr_z.Get_Cq_b().ElementN(5) = -Phi_pi2.nm.matrix[2, 2];
}
// Calculate violation of the dot constraint
ChVector u1 = frame1_abs.GetA().Get_A_Xaxis();
ChVector v2 = frame2_abs.GetA().Get_A_Yaxis();
m_C.matrix.SetElement(3, 0, ChVector.Vdot(u1, v2));
// Compute Jacobian of the dot constraint
// dot(u1_abs, v2_abs) = 0
{
ChMatrix33 <double> mat1 = Body1.GetA() * m_u1_tilde;
ChMatrix33 <double> mat2 = Body2.GetA() * m_v2_tilde;
ChVector Phi_pi1 = mat1.MatrT_x_Vect(v2);
ChVector Phi_pi2 = mat2.MatrT_x_Vect(u1);
m_cnstr_dot.Get_Cq_a().ElementN(0) = 0;
m_cnstr_dot.Get_Cq_a().ElementN(1) = 0;
m_cnstr_dot.Get_Cq_a().ElementN(2) = 0;
m_cnstr_dot.Get_Cq_a().ElementN(3) = -Phi_pi1.x;
m_cnstr_dot.Get_Cq_a().ElementN(4) = -Phi_pi1.y;
m_cnstr_dot.Get_Cq_a().ElementN(5) = -Phi_pi1.z;
m_cnstr_dot.Get_Cq_b().ElementN(0) = 0;
m_cnstr_dot.Get_Cq_b().ElementN(1) = 0;
m_cnstr_dot.Get_Cq_b().ElementN(2) = 0;
m_cnstr_dot.Get_Cq_b().ElementN(3) = -Phi_pi2.x;
m_cnstr_dot.Get_Cq_b().ElementN(4) = -Phi_pi2.y;
m_cnstr_dot.Get_Cq_b().ElementN(5) = -Phi_pi2.z;
}
}
//
// UPDATING FUNCTIONS
//
/// Override _all_ time, jacobian etc. updating.
public override void update(double mytime, bool update_assets = true)
{
// Inherit time changes of parent class (ChLink), basically doing nothing :)
base.update(mytime, update_assets);
if (this.Body1 != null && this.Body2 != null)
{
this.mask.SetTwoBodiesVariables(Body1.Variables(), Body2.Variables());
ChFrame <double> aframe = ChFrame <double> .BitShiftRight(this.frame1, (this.Body1));
ChVector p1_abs = aframe.GetPos();
ChFrame <double> aframe2 = ChFrame <double> .BitShiftRight(this.frame2, (this.Body2));
ChVector p2_abs = aframe2.GetPos();
ChFrame <double> bframe = new ChFrame <double>();
(this.Body2).TransformParentToLocal(aframe, bframe);
this.frame2.TransformParentToLocal(bframe, aframe);
// Now 'aframe' contains the position/rotation of frame 1 respect to frame 2, in frame 2 coords.
//***TODO*** check if it is faster to do aframe2.TransformParentToLocal(aframe, bframe); instead of two transforms above
ChMatrix33 <double> Jx1 = new ChMatrix33 <double>(0);
ChMatrix33 <double> Jx2 = new ChMatrix33 <double>(0);
ChMatrix33 <double> Jr1 = new ChMatrix33 <double>(0);
ChMatrix33 <double> Jr2 = new ChMatrix33 <double>(0);
ChMatrix33 <double> Jw1 = new ChMatrix33 <double>(0);
ChMatrix33 <double> Jw2 = new ChMatrix33 <double>(0);
ChMatrix33 <double> mtempM = new ChMatrix33 <double>(0);
ChMatrix33 <double> mtempQ = new ChMatrix33 <double>(0);
ChMatrix33 <double> abs_plane = new ChMatrix33 <double>(0);
abs_plane.nm.matrix.MatrMultiply(Body2.GetA().nm.matrix, frame2.GetA().nm.matrix);
Jx1.nm.matrix.CopyFromMatrixT(abs_plane.nm.matrix);
Jx2.nm.matrix.CopyFromMatrixT(abs_plane.nm.matrix);
Jx2.nm.matrix.MatrNeg();
Jw1.nm.matrix.MatrTMultiply(abs_plane.nm.matrix, Body1.GetA().nm.matrix);
Jw2.nm.matrix.MatrTMultiply(abs_plane.nm.matrix, Body2.GetA().nm.matrix);
mtempM.Set_X_matrix(frame1.GetPos());
Jr1.nm.matrix.MatrMultiply(Jw1.nm.matrix, mtempM.nm.matrix);
Jr1.nm.matrix.MatrNeg();
mtempM.Set_X_matrix(frame2.GetPos());
Jr2.nm.matrix.MatrMultiply(Jw2.nm.matrix, mtempM.nm.matrix);
ChVector p2p1_base2 = (Body2.GetA()).MatrT_x_Vect(ChVector.Vsub(p1_abs, p2_abs));
mtempM.Set_X_matrix(p2p1_base2);
mtempQ.nm.matrix.MatrTMultiply(frame2.GetA().nm.matrix, mtempM.nm.matrix);
Jr2.nm.matrix.MatrInc(mtempQ.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.
// For small misalignment this effect is almost insignificant cause [Fp(q_resid)]=[I],
// but otherwise it is needed (if you want to use the stabilization term - if not, you can live without).
mtempM.Set_X_matrix((aframe.GetRot().GetVector()) * 0.5);
mtempM.nm.matrix[0, 0] = 0.5 * aframe.GetRot().e0;
mtempM.nm.matrix[1, 1] = 0.5 * aframe.GetRot().e0;
mtempM.nm.matrix[2, 2] = 0.5 * aframe.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)
{
this.C.matrix.ElementN(nc) = aframe.GetPos().x;
this.mask.Constr_N(nc).Get_Cq_a().PasteClippedMatrix(Jx1.nm.matrix, 0, 0, 1, 3, 0, 0);
this.mask.Constr_N(nc).Get_Cq_a().PasteClippedMatrix(Jr1.nm.matrix, 0, 0, 1, 3, 0, 3);
this.mask.Constr_N(nc).Get_Cq_b().PasteClippedMatrix(Jx2.nm.matrix, 0, 0, 1, 3, 0, 0);
this.mask.Constr_N(nc).Get_Cq_b().PasteClippedMatrix(Jr2.nm.matrix, 0, 0, 1, 3, 0, 3);
nc++;
}
if (c_y)
{
this.C.matrix.ElementN(nc) = aframe.GetPos().y;
this.mask.Constr_N(nc).Get_Cq_a().PasteClippedMatrix(Jx1.nm.matrix, 1, 0, 1, 3, 0, 0);
this.mask.Constr_N(nc).Get_Cq_a().PasteClippedMatrix(Jr1.nm.matrix, 1, 0, 1, 3, 0, 3);
this.mask.Constr_N(nc).Get_Cq_b().PasteClippedMatrix(Jx2.nm.matrix, 1, 0, 1, 3, 0, 0);
this.mask.Constr_N(nc).Get_Cq_b().PasteClippedMatrix(Jr2.nm.matrix, 1, 0, 1, 3, 0, 3);
nc++;
}
if (c_z)
{
this.C.matrix.ElementN(nc) = aframe.GetPos().z;
this.mask.Constr_N(nc).Get_Cq_a().PasteClippedMatrix(Jx1.nm.matrix, 2, 0, 1, 3, 0, 0);
this.mask.Constr_N(nc).Get_Cq_a().PasteClippedMatrix(Jr1.nm.matrix, 2, 0, 1, 3, 0, 3);
this.mask.Constr_N(nc).Get_Cq_b().PasteClippedMatrix(Jx2.nm.matrix, 2, 0, 1, 3, 0, 0);
this.mask.Constr_N(nc).Get_Cq_b().PasteClippedMatrix(Jr2.nm.matrix, 2, 0, 1, 3, 0, 3);
nc++;
}
if (c_rx)
{
this.C.matrix.ElementN(nc) = aframe.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) = aframe.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) = aframe.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++;
}
}
}
// Updates motion laws, marker positions, etc.
public override void UpdateTime(double mytime)
{
// First, inherit to parent class
base.UpdateTime(mytime);
// Move markers 1 and 2 to align them as gear teeth
ChMatrix33 <double> ma1 = new ChMatrix33 <double>(0);
ChMatrix33 <double> ma2 = new ChMatrix33 <double>(0);
ChMatrix33 <double> mrotma = new ChMatrix33 <double>(0);
ChMatrix33 <double> marot_beta = new ChMatrix33 <double>(0);
ChVector mx;
ChVector my;
ChVector mz;
ChVector mr;
ChVector mmark1;
ChVector mmark2;
ChVector lastX;
ChVector vrota;
ChCoordsys newmarkpos = new ChCoordsys(new ChVector(0, 0, 0), new ChQuaternion(1, 0, 0, 0));
ChFrame <double> abs_shaft1 = ChFrame <double> .FNULL; // new ChFrame<double>();
ChFrame <double> abs_shaft2 = ChFrame <double> .FNULL; //new ChFrame<double>();
((ChFrame <double>)Body1).TransformLocalToParent(local_shaft1, abs_shaft1);
((ChFrame <double>)Body2).TransformLocalToParent(local_shaft2, abs_shaft2);
ChVector vbdist = ChVector.Vsub(Get_shaft_pos1(), Get_shaft_pos2());
// ChVector Trad1 = ChVector.Vnorm(ChVector.Vcross(Get_shaft_dir1(), ChVector.Vnorm(ChVector.Vcross(Get_shaft_dir1(), vbdist))));
// ChVector Trad2 = ChVector.Vnorm(ChVector.Vcross(ChVector.Vnorm(ChVector.Vcross(Get_shaft_dir2(), vbdist)), Get_shaft_dir2()));
double dist = ChVector.Vlength(vbdist);
// compute actual rotation of the two wheels (relative to truss).
ChVector md1 = abs_shaft1.GetA().MatrT_x_Vect(-vbdist);
md1.z = 0;
md1 = ChVector.Vnorm(md1);
ChVector md2 = abs_shaft2.GetA().MatrT_x_Vect(-vbdist);
md2.z = 0;
md2 = ChVector.Vnorm(md2);
double periodic_a1 = ChMaths.ChAtan2(md1.x, md1.y);
double periodic_a2 = ChMaths.ChAtan2(md2.x, md2.y);
double old_a1 = a1;
double old_a2 = a2;
double turns_a1 = Math.Floor(old_a1 / ChMaths.CH_C_2PI);
double turns_a2 = Math.Floor(old_a2 / ChMaths.CH_C_2PI);
double a1U = turns_a1 * ChMaths.CH_C_2PI + periodic_a1 + ChMaths.CH_C_2PI;
double a1M = turns_a1 * ChMaths.CH_C_2PI + periodic_a1;
double a1L = turns_a1 * ChMaths.CH_C_2PI + periodic_a1 - ChMaths.CH_C_2PI;
a1 = a1M;
if (Math.Abs(a1U - old_a1) < Math.Abs(a1M - old_a1))
{
a1 = a1U;
}
if (Math.Abs(a1L - a1) < Math.Abs(a1M - a1))
{
a1 = a1L;
}
double a2U = turns_a2 * ChMaths.CH_C_2PI + periodic_a2 + ChMaths.CH_C_2PI;
double a2M = turns_a2 * ChMaths.CH_C_2PI + periodic_a2;
double a2L = turns_a2 * ChMaths.CH_C_2PI + periodic_a2 - ChMaths.CH_C_2PI;
a2 = a2M;
if (Math.Abs(a2U - old_a2) < Math.Abs(a2M - old_a2))
{
a2 = a2U;
}
if (Math.Abs(a2L - a2) < Math.Abs(a2M - a2))
{
a2 = a2L;
}
// compute new markers coordsystem alignment
my = ChVector.Vnorm(vbdist);
mz = Get_shaft_dir1();
mx = ChVector.Vnorm(ChVector.Vcross(my, mz));
mr = ChVector.Vnorm(ChVector.Vcross(mz, mx));
mz = ChVector.Vnorm(ChVector.Vcross(mx, my));
ChVector mz2, mx2, mr2, my2;
my2 = my;
mz2 = Get_shaft_dir2();
mx2 = ChVector.Vnorm(ChVector.Vcross(my2, mz2));
mr2 = ChVector.Vnorm(ChVector.Vcross(mz2, mx2));
ma1.Set_A_axis(mx, my, mz);
// rotate csys because of beta
vrota.x = 0.0;
vrota.y = beta;
vrota.z = 0.0;
mrotma.Set_A_Rxyz(vrota);
marot_beta.nm.matrix.MatrMultiply(ma1.nm.matrix, mrotma.nm.matrix);
// rotate csys because of alpha
vrota.x = 0.0;
vrota.y = 0.0;
vrota.z = alpha;
if (react_force.x < 0)
{
vrota.z = alpha;
}
else
{
vrota.z = -alpha;
}
mrotma.Set_A_Rxyz(vrota);
ma1.nm.matrix.MatrMultiply(marot_beta.nm.matrix, mrotma.nm.matrix);
ma2.nm.matrix.CopyFromMatrix(ma1.nm.matrix);
// is a bevel gear?
double be = Math.Acos(ChVector.Vdot(Get_shaft_dir1(), Get_shaft_dir2()));
bool is_bevel = true;
if (Math.Abs(ChVector.Vdot(Get_shaft_dir1(), Get_shaft_dir2())) > 0.96)
{
is_bevel = false;
}
// compute wheel radii so that:
// w2 = - tau * w1
if (!is_bevel)
{
double pardist = ChVector.Vdot(mr, vbdist);
double inv_tau = 1.0 / tau;
if (!epicyclic)
{
r2 = pardist - pardist / (inv_tau + 1.0);
}
else
{
r2 = pardist - (tau * pardist) / (tau - 1.0);
}
r1 = r2 * tau;
}
else
{
double gamma2;
if (!epicyclic)
{
gamma2 = be / (tau + 1.0);
}
else
{
gamma2 = be / (-tau + 1.0);
}
double al = ChMaths.CH_C_PI - Math.Acos(ChVector.Vdot(Get_shaft_dir2(), my));
double te = ChMaths.CH_C_PI - al - be;
double fd = Math.Sin(te) * (dist / Math.Sin(be));
r2 = fd * Math.Tan(gamma2);
r1 = r2 * tau;
}
// compute markers positions, supposing they
// stay on the ideal wheel contact point
mmark1 = ChVector.Vadd(Get_shaft_pos2(), ChVector.Vmul(mr2, r2));
mmark2 = mmark1;
contact_pt = mmark1;
// correct marker 1 position if phasing is not correct
if (checkphase)
{
double realtau = tau;
if (epicyclic)
{
realtau = -tau;
}
double m_delta;
m_delta = -(a2 / realtau) - a1 - phase;
if (m_delta > ChMaths.CH_C_PI)
{
m_delta -= (ChMaths.CH_C_2PI); // range -180..+180 is better than 0...360
}
if (m_delta > (ChMaths.CH_C_PI / 4.0))
{
m_delta = (ChMaths.CH_C_PI / 4.0); // phase correction only in +/- 45°
}
if (m_delta < -(ChMaths.CH_C_PI / 4.0))
{
m_delta = -(ChMaths.CH_C_PI / 4.0);
}
vrota.x = vrota.y = 0.0;
vrota.z = -m_delta;
mrotma.Set_A_Rxyz(vrota); // rotate about Z of shaft to correct
mmark1 = abs_shaft1.GetA().MatrT_x_Vect(ChVector.Vsub(mmark1, Get_shaft_pos1()));
mmark1 = mrotma.Matr_x_Vect(mmark1);
mmark1 = ChVector.Vadd(abs_shaft1.GetA().Matr_x_Vect(mmark1), Get_shaft_pos1());
}
// Move Shaft 1 along its direction if not aligned to wheel
double offset = ChVector.Vdot(Get_shaft_dir1(), (contact_pt - Get_shaft_pos1()));
ChVector moff = Get_shaft_dir1() * offset;
if (Math.Abs(offset) > 0.0001)
{
local_shaft1.SetPos(local_shaft1.GetPos() + Body1.TransformDirectionParentToLocal(moff));
}
// ! Require that the BDF routine of marker won't handle speed and acc.calculus of the moved marker 2!
marker2.SetMotionType(ChMarker.eChMarkerMotion.M_MOTION_EXTERNAL);
marker1.SetMotionType(ChMarker.eChMarkerMotion.M_MOTION_EXTERNAL);
// move marker1 in proper positions
newmarkpos.pos = mmark1;
newmarkpos.rot = ma1.Get_A_quaternion();
marker1.Impose_Abs_Coord(newmarkpos); // move marker1 into teeth position
// move marker2 in proper positions
newmarkpos.pos = mmark2;
newmarkpos.rot = ma2.Get_A_quaternion();
marker2.Impose_Abs_Coord(newmarkpos); // move marker2 into teeth position
// imposed relative positions/speeds
deltaC.pos = ChVector.VNULL;
deltaC_dt.pos = ChVector.VNULL;
deltaC_dtdt.pos = ChVector.VNULL;
deltaC.rot = ChQuaternion.QUNIT; // no relative rotations imposed!
deltaC_dt.rot = ChQuaternion.QNULL;
deltaC_dtdt.rot = ChQuaternion.QNULL;
}
