/// Override _all_ time, jacobian etc. updating.
/// In detail, it computes jacobians, violations, etc. and stores
/// results in inner structures.
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);
// compute jacobians
ChVector AbsDist = Body1.TransformPointLocalToParent(pos1) - Body2.TransformPointLocalToParent(pos2);
curr_dist = AbsDist.Length();
ChVector D2abs = ChVector.Vnorm(AbsDist);
ChVector D2relB = Body2.TransformDirectionParentToLocal(D2abs);
ChVector D2relA = Body1.TransformDirectionParentToLocal(D2abs);
ChVector CqAx = D2abs;
ChVector CqBx = -D2abs;
ChVector CqAr = -ChVector.Vcross(D2relA, pos1);
ChVector CqBr = ChVector.Vcross(D2relB, pos2);
Cx.Get_Cq_a().ElementN(0) = CqAx.x;
Cx.Get_Cq_a().ElementN(1) = CqAx.y;
Cx.Get_Cq_a().ElementN(2) = CqAx.z;
Cx.Get_Cq_a().ElementN(3) = CqAr.x;
Cx.Get_Cq_a().ElementN(4) = CqAr.y;
Cx.Get_Cq_a().ElementN(5) = CqAr.z;
Cx.Get_Cq_b().ElementN(0) = CqBx.x;
Cx.Get_Cq_b().ElementN(1) = CqBx.y;
Cx.Get_Cq_b().ElementN(2) = CqBx.z;
Cx.Get_Cq_b().ElementN(3) = CqBr.x;
Cx.Get_Cq_b().ElementN(4) = CqBr.y;
Cx.Get_Cq_b().ElementN(5) = CqBr.z;
//***TO DO*** C_dt? C_dtdt? (may be never used..)
}
/// Get the link coordinate system, expressed relative to Body2 (the 'master'
/// body). This represents the 'main' reference of the link: reaction forces
/// are expressed in this coordinate system.
/// (It is the coordinate system of the contact plane relative to Body2)
public override ChCoordsys GetLinkRelativeCoords()
{
//ChVector D2local;
ChVector D2temp = (ChVector.Vnorm(Body1.TransformPointLocalToParent(pos1) - Body2.TransformPointLocalToParent(pos2)));
ChVector D2rel = Body2.TransformDirectionParentToLocal(D2temp);
ChVector Vx = new ChVector(0, 0, 0), Vy = new ChVector(0, 0, 0), Vz = new ChVector(0, 0, 0);
//ChMatrix33<double> rel_matrix = new ChMatrix33<double>();
ChVector.XdirToDxDyDz(D2rel, ChVector.VECT_Y, ref Vx, ref Vy, ref Vz);
rel_matrix.Set_A_axis(Vx, Vy, Vz);
ChQuaternion Ql2 = rel_matrix.Get_A_quaternion();
return(new ChCoordsys(pos2, Ql2));
}
/// Initialize this joint by specifying the two bodies to be connected, a point
/// and a direction on body1 defining the revolute joint, and a point on the
/// second body defining the spherical joint. If local = true, it is assumed
/// that these quantities are specified in the local body frames. Otherwise,
/// it is assumed that they are specified in the absolute frame. The imposed
/// distance between the two points can be either inferred from the provided
/// configuration (auto_distance = true) or specified explicitly.
public void Initialize(ChBodyFrame body1, //< first frame (revolute side)
ChBodyFrame body2, //< second frame (spherical side)
bool local, //< true if data given in body local frames
ChVector pos1, //< point on first frame (center of revolute)
ChVector dir1, //< direction of revolute on first frame
ChVector pos2, //< point on second frame (center of spherical)
bool auto_distance = true, //< true if imposed distance equal to |pos1 - po2|
double distance = 0 //< imposed distance (used only if auto_distance = false)
)
{
Body1 = body1;
Body2 = body2;
m_cnstr_dist.SetVariables(Body1.Variables(), Body2.Variables());
m_cnstr_dot.SetVariables(Body1.Variables(), Body2.Variables());
ChVector pos1_abs;
ChVector pos2_abs;
ChVector dir1_abs;
if (local)
{
m_pos1 = pos1;
m_pos2 = pos2;
m_dir1 = ChVector.Vnorm(dir1);
pos1_abs = Body1.TransformPointLocalToParent(m_pos1);
pos2_abs = Body2.TransformPointLocalToParent(m_pos2);
dir1_abs = Body1.TransformDirectionLocalToParent(m_dir1);
}
else
{
pos1_abs = pos1;
pos2_abs = pos2;
dir1_abs = ChVector.Vnorm(dir1);
m_pos1 = Body1.TransformPointParentToLocal(pos1_abs);
m_pos2 = Body2.TransformPointParentToLocal(pos2_abs);
m_dir1 = Body1.TransformDirectionParentToLocal(dir1_abs);
}
ChVector d12_abs = pos2_abs - pos1_abs;
m_cur_dist = d12_abs.Length();
m_dist = auto_distance ? m_cur_dist : distance;
m_cur_dot = ChVector.Vdot(d12_abs, dir1_abs);
}
/// Inherits, then also adds the spring custom forces to the C_force and C_torque.
public override void UpdateForces(double mytime)
{
// Inherit force computation:
// also base class can add its own forces.
base.UpdateForces(mytime);
spr_react = 0.0;
ChVector m_force;
double deform = Get_SpringDeform();
spr_react = spr_f * mod_f_time.Get_y(ChTime);
spr_react -= (spr_k * mod_k_d.Get_y(deform) * mod_k_speed.Get_y(dist_dt)) * (deform);
spr_react -= (spr_r * mod_r_d.Get_y(deform) * mod_r_speed.Get_y(dist_dt)) * (dist_dt);
m_force = ChVector.Vmul(ChVector.Vnorm(relM.pos), spr_react);
C_force = ChVector.Vadd(C_force, m_force);
}
/// Use this function after object creation, to initialize it, given
/// the 1D shaft and 3D body to join.
/// Each item must belong to the same ChSystem.
/// Direction is expressed in the local coordinates of the body.
public bool Initialize(ChShaft mshaft, //< shaft to join
ChBodyFrame mbody, //< body to join
ChVector mdir //< the direction of the shaft on 3D body (applied on COG: pure torque)
)
{
ChShaft mm1 = mshaft;
ChBodyFrame mm2 = mbody;
//Debug.Assert(mm1 == null && mm2 == null);
shaft = mm1;
body.BodyFrame = mm2;
shaft_dir = ChVector.Vnorm(mdir);
constraint.SetVariables(mm1.Variables(), mm2.Variables());
SetSystem(shaft.GetSystem());
return(true);
}
public static void Q_to_AngAxis(ChQuaternion quat, ref double angle, ref ChVector axis)
{
if (Mathfx.Abs(quat.e0) < 0.99999999)
{
double arg = Math.Acos(quat.e0);
double invsine = 1 / Math.Sin(arg);
ChVector vtemp = ChVector.VNULL; //new ChVector(0, 0, 0);
vtemp.x = invsine * quat.e1;
vtemp.y = invsine * quat.e2;
vtemp.z = invsine * quat.e3;
angle = 2 * arg;
axis = ChVector.Vnorm(vtemp);
}
else
{
axis.x = 1;
axis.y = 0;
axis.z = 0;
angle = 0;
}
}
// -----------------------------------------------------------------------------
// Draw a spring in 3D space, with given color.
// -----------------------------------------------------------------------------
public static void drawSpring(double radius,
ChVector start,
ChVector end,
int mresolution,
double turns)
{
ChMatrix33 <double> rel_matrix = new ChMatrix33 <double>(0);
ChVector dist = end - start;
ChVector Vx = new ChVector(0, 0, 0);
ChVector Vy = new ChVector(0, 0, 0);
ChVector Vz = new ChVector(0, 0, 0);
double length = dist.Length();
ChVector dir = ChVector.Vnorm(dist);
ChVector.XdirToDxDyDz(dir, ChVector.VECT_Y, ref Vx, ref Vy, ref Vz);
rel_matrix.Set_A_axis(Vx, Vy, Vz);
ChQuaternion Q12 = rel_matrix.Get_A_quaternion();
ChCoordsys mpos = new ChCoordsys(start, Q12);
double phaseA = 0;
double phaseB = 0;
double heightA = 0;
double heightB = 0;
for (int iu = 1; iu <= mresolution; iu++)
{
phaseB = turns * ChMaths.CH_C_2PI * (double)iu / (double)mresolution;
heightB = length * ((double)iu / mresolution);
ChVector V1 = new ChVector(heightA, radius * Math.Cos(phaseA), radius * Math.Sin(phaseA));
ChVector V2 = new ChVector(heightB, radius * Math.Cos(phaseB), radius * Math.Sin(phaseB));
Gizmos.color = new Color(255, 255, 0);
Gizmos.DrawLine(new Vector3((float)mpos.TransformLocalToParent(V1).x, (float)mpos.TransformLocalToParent(V1).y, (float)mpos.TransformLocalToParent(V1).z),
new Vector3((float)mpos.TransformLocalToParent(V2).x, (float)mpos.TransformLocalToParent(V2).y, (float)mpos.TransformLocalToParent(V2).z));
phaseA = phaseB;
heightA = heightB;
}
}
/// 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;
}
//
// UPDATING
//
/// Updates the time.dependant variables (ex: ChFunction objects
/// which impose the body-relative motion, etc.)
public void UpdateTime(double mytime)
{
ChCoordsys csys = new ChCoordsys(new ChVector(0, 0, 0), new ChQuaternion(1, 0, 0, 0));
ChCoordsys csys_dt = new ChCoordsys(new ChVector(0, 0, 0), new ChQuaternion(1, 0, 0, 0));
ChCoordsys csys_dtdt = new ChCoordsys(new ChVector(0, 0, 0), new ChQuaternion(1, 0, 0, 0));
ChQuaternion qtemp;// = new ChQuaternion(1, 0, 0, 0);
double ang, ang_dt, ang_dtdt;
ChTime = mytime;
// if a imposed motion (keyframed movement) affects the marker position (example,from R3D animation system),
// compute the speed and acceleration values by BDF (example,see the UpdatedExternalTime() function, later)
// so the updating via motion laws can be skipped!
if (motion_type == eChMarkerMotion.M_MOTION_KEYFRAMED)
{
return;
}
// skip relative-position-functions evaluation also if
// someone is already handling this from outside..
if (motion_type == eChMarkerMotion.M_MOTION_EXTERNAL)
{
return;
}
// positions:
// update positions: rel_pos
csys.pos.x = motion_X.Get_y(mytime);
csys.pos.y = motion_Y.Get_y(mytime);
csys.pos.z = motion_Z.Get_y(mytime);
if (motion_X.Get_Type() != ChFunction.FunctionType.FUNCT_MOCAP)
{
csys.pos += rest_coord.pos;
}
// update speeds: rel_pos_dt
csys_dt.pos.x = motion_X.Get_y_dx(mytime);
csys_dt.pos.y = motion_Y.Get_y_dx(mytime);
csys_dt.pos.z = motion_Z.Get_y_dx(mytime);
// update accelerations
csys_dtdt.pos.x = motion_X.Get_y_dxdx(mytime);
csys_dtdt.pos.y = motion_Y.Get_y_dxdx(mytime);
csys_dtdt.pos.z = motion_Z.Get_y_dxdx(mytime);
// rotations:
ang = motion_ang.Get_y(mytime);
ang_dt = motion_ang.Get_y_dx(mytime);
ang_dtdt = motion_ang.Get_y_dxdx(mytime);
if ((ang != 0) || (ang_dt != 0) || (ang_dtdt != 0))
{
// update q
ChVector motion_axis_versor = ChVector.Vnorm(motion_axis);
qtemp = ChQuaternion.Q_from_AngAxis2(ang, motion_axis_versor);
csys.rot = ChQuaternion.Qcross(qtemp, rest_coord.rot);
// update q_dt
csys_dt.rot = ChQuaternion.Qdt_from_AngAxis(csys.rot, ang_dt, motion_axis_versor);
// update q_dtdt
csys_dtdt.rot = ChQuaternion.Qdtdt_from_AngAxis(ang_dtdt, motion_axis_versor, csys.rot, csys_dt.rot);
}
else
{
csys.rot = FrameMoving.coord.rot; // rel_pos.rot;
csys_dt.rot = ChQuaternion.QNULL;
csys_dtdt.rot = ChQuaternion.QNULL;
}
// Set the position, speed and acceleration in relative space,
// automatically getting also the absolute values,
if (!(csys == this.FrameMoving.coord))
{
FrameMoving.SetCoord(csys);
}
if (!(csys_dt == this.FrameMoving.coord_dt) || !(csys_dt.rot == new ChQuaternion(0, 0, 0, 0)))
{
FrameMoving.SetCoord_dt(csys_dt);
}
if (!(csys_dtdt == this.FrameMoving.coord_dtdt) || !(csys_dtdt.rot == new ChQuaternion(0, 0, 0, 0)))
{
FrameMoving.SetCoord_dtdt(csys_dtdt);
}
}
/// Updates motion laws, etc. for the impose rotation / impose speed modes
public override void UpdateTime(double mytime)
{
// First, inherit to parent class
base.UpdateTime(mytime);
if (!IsActive())
{
return;
}
// DEFAULTS compute rotation vars...
// by default for torque control..
motion_axis = ChVector.VECT_Z; // motion axis is always the marker2 Z axis (in m2 relative coords)
mot_rot = relAngle;
mot_rot_dt = ChVector.Vdot(relWvel, motion_axis);
mot_rot_dtdt = ChVector.Vdot(relWacc, motion_axis);
mot_rerot = mot_rot / mot_tau;
mot_rerot_dt = mot_rot_dt / mot_tau;
mot_rerot_dtdt = mot_rot_dtdt / mot_tau;
// nothing more to do here for torque control
if (eng_mode == eCh_eng_mode.ENG_MODE_TORQUE)
{
return;
}
// If LEARN MODE, just record motion
if (learn)
{
deltaC.pos = ChVector.VNULL;
deltaC_dt.pos = ChVector.VNULL;
deltaC_dtdt.pos = ChVector.VNULL;
if (!(limit_Rx.Get_active() || limit_Ry.Get_active() || limit_Rz.Get_active()))
{
deltaC.rot = ChQuaternion.QUNIT;
deltaC_dt.rot = ChQuaternion.QNULL;
deltaC_dtdt.rot = ChQuaternion.QNULL;
}
if (eng_mode == eCh_eng_mode.ENG_MODE_ROTATION)
{
if (rot_funct.Get_Type() != ChFunction.FunctionType.FUNCT_RECORDER)
{
rot_funct = new ChFunction_Recorder();
}
// record point
double rec_rot = relAngle; // ***TO DO*** compute also rotations with cardano mode?
if (impose_reducer)
{
rec_rot = rec_rot / mot_tau;
}
ChFunction_Recorder rec = (ChFunction_Recorder)rot_funct;
rec.AddPoint(mytime, rec_rot, 1); // x=t
}
if (eng_mode == eCh_eng_mode.ENG_MODE_SPEED)
{
if (spe_funct.Get_Type() != ChFunction.FunctionType.FUNCT_RECORDER)
{
spe_funct = new ChFunction_Recorder();
}
// record point
double rec_spe = ChVector.Vlength(relWvel); // ***TO DO*** compute also with cardano mode?
if (impose_reducer)
{
rec_spe = rec_spe / mot_tau;
}
ChFunction_Recorder rec = (ChFunction_Recorder)spe_funct;
rec.AddPoint(mytime, rec_spe, 1); // x=t
}
}
if (learn)
{
return; // no need to go on further...--.>>>
}
// Impose relative positions/speeds
deltaC.pos = ChVector.VNULL;
deltaC_dt.pos = ChVector.VNULL;
deltaC_dtdt.pos = ChVector.VNULL;
if (eng_mode == eCh_eng_mode.ENG_MODE_ROTATION)
{
if (impose_reducer)
{
mot_rerot = rot_funct.Get_y(ChTime);
mot_rerot_dt = rot_funct.Get_y_dx(ChTime);
mot_rerot_dtdt = rot_funct.Get_y_dxdx(ChTime);
mot_rot = mot_rerot * mot_tau;
mot_rot_dt = mot_rerot_dt * mot_tau;
mot_rot_dtdt = mot_rerot_dtdt * mot_tau;
}
else
{
mot_rot = rot_funct.Get_y(ChTime);
mot_rot_dt = rot_funct.Get_y_dx(ChTime);
mot_rot_dtdt = rot_funct.Get_y_dxdx(ChTime);
mot_rerot = mot_rot / mot_tau;
mot_rerot_dt = mot_rot_dt / mot_tau;
mot_rerot_dtdt = mot_rot_dtdt / mot_tau;
}
deltaC.rot = ChQuaternion.Q_from_AngAxis2(mot_rot, motion_axis);
deltaC_dt.rot = ChQuaternion.Qdt_from_AngAxis(deltaC.rot, mot_rot_dt, motion_axis);
deltaC_dtdt.rot = ChQuaternion.Qdtdt_from_AngAxis(mot_rot_dtdt, motion_axis, deltaC.rot, deltaC_dt.rot);
}
if (eng_mode == eCh_eng_mode.ENG_MODE_SPEED)
{
if (impose_reducer)
{
mot_rerot_dt = spe_funct.Get_y(ChTime);
mot_rerot_dtdt = spe_funct.Get_y_dx(ChTime);
mot_rot_dt = mot_rerot_dt * mot_tau;
mot_rot_dtdt = mot_rerot_dtdt * mot_tau;
}
else
{
mot_rot_dt = spe_funct.Get_y(ChTime);
mot_rot_dtdt = spe_funct.Get_y_dx(ChTime);
mot_rerot_dt = mot_rot_dt / mot_tau;
mot_rerot_dtdt = mot_rot_dtdt / mot_tau;
}
deltaC.rot = ChQuaternion.Qnorm(GetRelM().rot); // just keep current position, -assume always good after integration-.
ChMatrix33 <double> relA = new ChMatrix33 <double>(0);
relA.Set_A_quaternion(GetRelM().rot); // ..but adjust to keep Z axis aligned to shaft, anyway!
ChVector displaced_z_axis = relA.Get_A_Zaxis();
ChVector adjustment = ChVector.Vcross(displaced_z_axis, ChVector.VECT_Z);
deltaC.rot = ChQuaternion.Q_from_AngAxis2(ChVector.Vlength(adjustment), ChVector.Vnorm(adjustment)) % deltaC.rot;
deltaC_dt.rot = ChQuaternion.Qdt_from_AngAxis(deltaC.rot, mot_rot_dt, motion_axis);
deltaC_dtdt.rot = ChQuaternion.Qdtdt_from_AngAxis(mot_rot_dtdt, motion_axis, deltaC.rot, deltaC_dt.rot);
}
}
/// Inherits, and updates the C_force and C_torque 'intuitive' forces,
/// adding the effects of the contained ChLinkForce objects.
/// (Default: inherits parent UpdateForces(), then C_force and C_torque are
/// incremented with the Link::ChLinkForces objects)
public override void UpdateForces(double mytime)
{
base.UpdateForces(mytime);
// ** Child class can inherit this method. The parent implementation must
// be called _before_ adding further custom forces.
ChVector m_force; // = new ChVector(0, 0, 0); // initialize to zero the m1-m2 force/torque
ChVector m_torque; // = new ChVector(0, 0, 0); // 'intuitive' vectors (can be transformed&added later into Qf)
// COMPUTE THE FORCES IN THE LINK, FOR EXAMPLE
// CAUSED BY SPRINGS
// NOTE!!!!! C_force and C_torque are considered in the reference coordsystem
// of marker2 (the MAIN marker), and their application point is considered the
// origin of marker1 (the SLAVE marker)
// 1)========== the generic spring-damper
if (force_D != null && force_D.Get_active())
{
double dfor;
dfor = force_D.Get_Force((dist - d_restlength), dist_dt, ChTime);
m_force = ChVector.Vmul(ChVector.Vnorm(relM.pos), dfor);
C_force = ChVector.Vadd(C_force, m_force);
}
// 2)========== the generic torsional spring / torsional damper
if (force_R != null && force_R.Get_active())
{
double tor;
// 1) the tors. spring
tor = force_R.Get_Force(relAngle, 0, ChTime);
m_torque = ChVector.Vmul(relAxis, tor);
C_torque = ChVector.Vadd(C_torque, m_torque);
// 2) the tors. damper
double angle_dt = ChVector.Vlength(relWvel);
tor = force_R.Get_Force(0, angle_dt, ChTime);
m_torque = ChVector.Vmul(ChVector.Vnorm(relWvel), tor);
C_torque = ChVector.Vadd(C_torque, m_torque);
}
// 3)========== the XYZ forces
m_force = ChVector.VNULL;
if (force_X != null && force_X.Get_active())
{
m_force.x = force_X.Get_Force(relM.pos.x, relM_dt.pos.x, ChTime);
}
if (force_Y != null && force_Y.Get_active())
{
m_force.y = force_Y.Get_Force(relM.pos.y, relM_dt.pos.y, ChTime);
}
if (force_Z != null && force_Z.Get_active())
{
m_force.z = force_Z.Get_Force(relM.pos.z, relM_dt.pos.z, ChTime);
}
C_force = ChVector.Vadd(C_force, m_force);
// 4)========== the RxRyRz forces (torques)
m_torque = new ChVector(0, 0, 0);
if (force_Rx != null && force_Rx.Get_active())
{
m_torque.x = force_Rx.Get_Force(relRotaxis.x, relWvel.x, ChTime);
}
if (force_Ry != null && force_Ry.Get_active())
{
m_torque.y = force_Ry.Get_Force(relRotaxis.y, relWvel.y, ChTime);
}
if (force_Rz != null && force_Rz.Get_active())
{
m_torque.z = force_Rz.Get_Force(relRotaxis.z, relWvel.z, ChTime);
}
C_torque = ChVector.Vadd(C_torque, m_torque);
}
/// Set the direction of the shaft respect to 3D body, as a
/// normalized vector expressed in the coordinates of the body.
/// The shaft applies only torque, about this axis.
public void SetShaftDirection(ChVector md)
{
shaft_dir = ChVector.Vnorm(md);
}
/// Get the master coordinate system for the assets (this will return the
/// absolute coordinate system of the 'master' marker2)
// public override ChFrame<double> GetAssetsFrame(int nclone = 0) { return marker2.GetAbsFrame(); }
//
// UPDATING FUNCTIONS
//
/// Updates auxiliary vars relM, relM_dt, relM_dtdt,
/// dist, dist_dt et simila.
public virtual void UpdateRelMarkerCoords()
{
// FOR ALL THE 6(or3) COORDINATES OF RELATIVE MOTION OF THE TWO MARKERS:
// COMPUTE THE relM, relM_dt relM_dtdt COORDINATES, AND AUXILIARY DATA (distance,etc.)
ChVector PQw = ChVector.Vsub(marker1.GetAbsCoord().pos, marker2.GetAbsCoord().pos);
ChVector PQw_dt = ChVector.Vsub(marker1.GetAbsCoord_dt().pos, marker2.GetAbsCoord_dt().pos);
ChVector PQw_dtdt = ChVector.Vsub(marker1.GetAbsCoord_dtdt().pos, marker2.GetAbsCoord_dtdt().pos);
dist = ChVector.Vlength(PQw); // distance between origins, modulus
dist_dt = ChVector.Vdot(ChVector.Vnorm(PQw), PQw_dt); // speed between origins, modulus.
ChVector vtemp1; // for intermediate calculus
ChVector vtemp2;
ChQuaternion qtemp1;
// ChMatrixNM<IntInterface.Three, IntInterface.Four> relGw = new ChMatrixNM<IntInterface.Three, IntInterface.Four>(0);
/* ChQuaternion q_AD;
* ChQuaternion q_BC;
* ChQuaternion q_8;
* ChVector q_4;*/
ChQuaternion temp1 = marker1.FrameMoving.GetCoord_dt().rot;
ChQuaternion temp2 = marker2.FrameMoving.GetCoord_dt().rot;
if (ChQuaternion.Qnotnull(temp1) || ChQuaternion.Qnotnull(temp2))
{
q_AD = // q'qqq + qqqq'
ChQuaternion.Qadd(ChQuaternion.Qcross(ChQuaternion.Qconjugate(marker2.FrameMoving.GetCoord_dt().rot),
ChQuaternion.Qcross(ChQuaternion.Qconjugate(marker2.GetBody().BodyFrame.GetCoord().rot),
ChQuaternion.Qcross((marker1.GetBody().BodyFrame.GetCoord().rot), (marker1.FrameMoving.GetCoord().rot)))),
ChQuaternion.Qcross(ChQuaternion.Qconjugate(marker2.FrameMoving.GetCoord().rot),
ChQuaternion.Qcross(ChQuaternion.Qconjugate(marker2.GetBody().BodyFrame.GetCoord().rot),
ChQuaternion.Qcross((marker1.GetBody().BodyFrame.GetCoord().rot), (marker1.FrameMoving.GetCoord_dt().rot)))));
}
else
{
//q_AD = ChQuaternion.QNULL;
q_BC = // qq'qq + qqq'q
ChQuaternion.Qadd(ChQuaternion.Qcross(ChQuaternion.Qconjugate(marker2.FrameMoving.GetCoord().rot),
ChQuaternion.Qcross(ChQuaternion.Qconjugate(marker2.GetBody().BodyFrame.GetCoord_dt().rot),
ChQuaternion.Qcross((marker1.GetBody().BodyFrame.GetCoord().rot), (marker1.FrameMoving.GetCoord().rot)))),
ChQuaternion.Qcross(ChQuaternion.Qconjugate(marker2.FrameMoving.GetCoord().rot),
ChQuaternion.Qcross(ChQuaternion.Qconjugate(marker2.GetBody().BodyFrame.GetCoord().rot),
ChQuaternion.Qcross((marker1.GetBody().BodyFrame.GetCoord_dt().rot), (marker1.FrameMoving.GetCoord().rot)))));
}
// q_8 = q''qqq + 2q'q'qq + 2q'qq'q + 2q'qqq'
// + 2qq'q'q + 2qq'qq' + 2qqq'q' + qqqq''
temp2 = marker2.FrameMoving.GetCoord_dtdt().rot;
if (ChQuaternion.Qnotnull(temp2))
{
q_8 = ChQuaternion.Qcross(ChQuaternion.Qconjugate(marker2.FrameMoving.GetCoord_dtdt().rot),
ChQuaternion.Qcross(ChQuaternion.Qconjugate(Body2.GetCoord().rot),
ChQuaternion.Qcross(Body1.GetCoord().rot,
marker1.FrameMoving.GetCoord().rot))); // q_dtdt'm2 * q'o2 * q,o1 * q,m1
}
else
{
//q_8 = ChQuaternion.QNULL;
temp1 = marker1.FrameMoving.GetCoord_dtdt().rot;
}
if (ChQuaternion.Qnotnull(temp1))
{
qtemp1 = ChQuaternion.Qcross(ChQuaternion.Qconjugate(marker2.FrameMoving.GetCoord().rot),
ChQuaternion.Qcross(ChQuaternion.Qconjugate(Body2.GetCoord().rot),
ChQuaternion.Qcross(Body1.GetCoord().rot,
marker1.FrameMoving.GetCoord_dtdt().rot))); // q'm2 * q'o2 * q,o1 * q_dtdt,m1
q_8 = ChQuaternion.Qadd(q_8, qtemp1);
}
temp2 = marker2.FrameMoving.GetCoord_dt().rot;
if (ChQuaternion.Qnotnull(temp2))
{
qtemp1 = ChQuaternion.Qcross(
ChQuaternion.Qconjugate(marker2.FrameMoving.GetCoord_dt().rot),
ChQuaternion.Qcross(ChQuaternion.Qconjugate(Body2.GetCoord_dt().rot), ChQuaternion.Qcross(Body1.GetCoord().rot, marker1.FrameMoving.GetCoord().rot)));
qtemp1 = ChQuaternion.Qscale(qtemp1, 2); // 2( q_dt'm2 * q_dt'o2 * q,o1 * q,m1)
q_8 = ChQuaternion.Qadd(q_8, qtemp1);
}
temp2 = marker2.FrameMoving.GetCoord_dt().rot;
if (ChQuaternion.Qnotnull(temp2))
{
qtemp1 = ChQuaternion.Qcross(
ChQuaternion.Qconjugate(marker2.FrameMoving.GetCoord_dt().rot),
ChQuaternion.Qcross(ChQuaternion.Qconjugate(Body2.GetCoord().rot), ChQuaternion.Qcross(Body1.GetCoord_dt().rot, marker1.FrameMoving.GetCoord().rot)));
qtemp1 = ChQuaternion.Qscale(qtemp1, 2); // 2( q_dt'm2 * q'o2 * q_dt,o1 * q,m1)
q_8 = ChQuaternion.Qadd(q_8, qtemp1);
}
temp1 = marker1.FrameMoving.GetCoord_dt().rot;
temp2 = marker2.FrameMoving.GetCoord_dt().rot;
if (ChQuaternion.Qnotnull(temp2) && ChQuaternion.Qnotnull(temp1))
{
qtemp1 = ChQuaternion.Qcross(
ChQuaternion.Qconjugate(marker2.FrameMoving.GetCoord_dt().rot),
ChQuaternion.Qcross(ChQuaternion.Qconjugate(Body2.GetCoord().rot), ChQuaternion.Qcross(Body1.GetCoord().rot, marker1.FrameMoving.GetCoord_dt().rot)));
qtemp1 = ChQuaternion.Qscale(qtemp1, 2); // 2( q_dt'm2 * q'o2 * q,o1 * q_dt,m1)
q_8 = ChQuaternion.Qadd(q_8, qtemp1);
}
qtemp1 =
ChQuaternion.Qcross(ChQuaternion.Qconjugate(marker2.FrameMoving.GetCoord().rot),
ChQuaternion.Qcross(ChQuaternion.Qconjugate(Body2.GetCoord_dt().rot), ChQuaternion.Qcross(Body1.GetCoord_dt().rot, marker1.FrameMoving.GetCoord().rot)));
qtemp1 = ChQuaternion.Qscale(qtemp1, 2); // 2( q'm2 * q_dt'o2 * q_dt,o1 * q,m1)
q_8 = ChQuaternion.Qadd(q_8, qtemp1);
temp1 = marker1.FrameMoving.GetCoord_dt().rot;
if (ChQuaternion.Qnotnull(temp1))
{
qtemp1 = ChQuaternion.Qcross(
ChQuaternion.Qconjugate(marker2.FrameMoving.GetCoord().rot),
ChQuaternion.Qcross(ChQuaternion.Qconjugate(Body2.GetCoord_dt().rot), ChQuaternion.Qcross(Body1.GetCoord().rot, marker1.FrameMoving.GetCoord_dt().rot)));
qtemp1 = ChQuaternion.Qscale(qtemp1, 2); // 2( q'm2 * q_dt'o2 * q,o1 * q_dt,m1)
q_8 = ChQuaternion.Qadd(q_8, qtemp1);
}
temp1 = marker1.FrameMoving.GetCoord_dt().rot;
if (ChQuaternion.Qnotnull(temp1))
{
qtemp1 = ChQuaternion.Qcross(
ChQuaternion.Qconjugate(marker2.FrameMoving.GetCoord().rot),
ChQuaternion.Qcross(ChQuaternion.Qconjugate(Body2.GetCoord().rot), ChQuaternion.Qcross(Body1.GetCoord_dt().rot, marker1.FrameMoving.GetCoord_dt().rot)));
qtemp1 = ChQuaternion.Qscale(qtemp1, 2); // 2( q'm2 * q'o2 * q_dt,o1 * q_dt,m1)
q_8 = ChQuaternion.Qadd(q_8, qtemp1);
}
// q_4 = [Adtdt]'[A]'q + 2[Adt]'[Adt]'q
// + 2[Adt]'[A]'qdt + 2[A]'[Adt]'qdt
// ChMatrix33<double> m2_Rel_A_dt = new ChMatrix33<double>(0);
marker2.FrameMoving.Compute_Adt(ref m2_Rel_A_dt);
// ChMatrix33<double> m2_Rel_A_dtdt = new ChMatrix33<double>(0);
marker2.FrameMoving.Compute_Adtdt(ref m2_Rel_A_dtdt);
vtemp1 = Body2.GetA_dt().MatrT_x_Vect(PQw);
vtemp2 = m2_Rel_A_dt.MatrT_x_Vect(vtemp1);
q_4 = ChVector.Vmul(vtemp2, 2); // 2[Aq_dt]'[Ao2_dt]'*Qpq,w
vtemp1 = Body2.GetA().MatrT_x_Vect(PQw_dt);
vtemp2 = m2_Rel_A_dt.MatrT_x_Vect(vtemp1);
vtemp2 = ChVector.Vmul(vtemp2, 2); // 2[Aq_dt]'[Ao2]'*Qpq,w_dt
q_4 = ChVector.Vadd(q_4, vtemp2);
vtemp1 = Body2.GetA_dt().MatrT_x_Vect(PQw_dt);
vtemp2 = marker2.FrameMoving.GetA().MatrT_x_Vect(vtemp1);
vtemp2 = ChVector.Vmul(vtemp2, 2); // 2[Aq]'[Ao2_dt]'*Qpq,w_dt
q_4 = ChVector.Vadd(q_4, vtemp2);
vtemp1 = Body2.GetA().MatrT_x_Vect(PQw);
vtemp2 = m2_Rel_A_dtdt.MatrT_x_Vect(vtemp1);
q_4 = ChVector.Vadd(q_4, vtemp2); // [Aq_dtdt]'[Ao2]'*Qpq,w
// ----------- RELATIVE MARKER COORDINATES
// relM.pos
relM.pos = marker2.FrameMoving.GetA().MatrT_x_Vect(Body2.GetA().MatrT_x_Vect(PQw));
// relM.rot
relM.rot = ChQuaternion.Qcross(ChQuaternion.Qconjugate(marker2.FrameMoving.GetCoord().rot),
ChQuaternion.Qcross(ChQuaternion.Qconjugate(marker2.GetBody().BodyFrame.GetCoord().rot),
ChQuaternion.Qcross((marker1.GetBody().BodyFrame.GetCoord().rot), (marker1.FrameMoving.GetCoord().rot))));
// relM_dt.pos
relM_dt.pos = ChVector.Vadd(ChVector.Vadd(m2_Rel_A_dt.MatrT_x_Vect(Body2.GetA().MatrT_x_Vect(PQw)),
marker2.FrameMoving.GetA().MatrT_x_Vect(Body2.GetA_dt().MatrT_x_Vect(PQw))),
marker2.FrameMoving.GetA().MatrT_x_Vect(Body2.GetA().MatrT_x_Vect(PQw_dt)));
// relM_dt.rot
relM_dt.rot = ChQuaternion.Qadd(q_AD, q_BC);
// relM_dtdt.pos
relM_dtdt.pos = ChVector.Vadd(ChVector.Vadd(marker2.FrameMoving.GetA().MatrT_x_Vect(Body2.GetA_dtdt().MatrT_x_Vect(PQw)),
marker2.FrameMoving.GetA().MatrT_x_Vect(Body2.GetA().MatrT_x_Vect(PQw_dtdt))),
q_4);
// relM_dtdt.rot
qtemp1 = ChQuaternion.Qcross(ChQuaternion.Qconjugate(marker2.FrameMoving.GetCoord().rot),
ChQuaternion.Qcross(ChQuaternion.Qconjugate(Body2.GetCoord_dtdt().rot),
ChQuaternion.Qcross(Body1.GetCoord().rot,
marker1.FrameMoving.GetCoord().rot))); // ( q'm2 * q_dtdt'o2 * q,o1 * q,m1)
relM_dtdt.rot = ChQuaternion.Qadd(q_8, qtemp1);
qtemp1 = ChQuaternion.Qcross(ChQuaternion.Qconjugate(marker2.FrameMoving.GetCoord().rot),
ChQuaternion.Qcross(ChQuaternion.Qconjugate(Body2.GetCoord().rot),
ChQuaternion.Qcross(Body1.GetCoord_dtdt().rot,
marker1.FrameMoving.GetCoord().rot))); // ( q'm2 * q'o2 * q_dtdt,o1 * q,m1)
relM_dtdt.rot = ChQuaternion.Qadd(relM_dtdt.rot, qtemp1); // = q_8 + qq''qq + qqq''q
// ... and also "user-friendly" relative coordinates:
// relAngle and relAxis
ChQuaternion.Q_to_AngAxis(relM.rot, ref relAngle, ref relAxis);
// flip rel rotation axis if jerky sign
if (relAxis.z < 0)
{
relAxis = ChVector.Vmul(relAxis, -1);
relAngle = -relAngle;
}
// rotation axis
relRotaxis = ChVector.Vmul(relAxis, relAngle);
// relWvel
ChFrame <double> .SetMatrix_Gw(ref relGw, relM.rot); // relGw.Set_Gw_matrix(relM.rot);
relWvel = relGw.matrix.Matr34_x_Quat(relM_dt.rot);
// relWacc
relWacc = relGw.matrix.Matr34_x_Quat(relM_dtdt.rot);
}
// Updates motion laws, marker positions, etc.
public override void UpdateTime(double mytime)
{
// First, inherit to parent class
base.UpdateTime(mytime);
// If LEARN MODE, just record motion
if (learn)
{
/* do not change deltas, in free mode maybe that 'limit on X' changed them
* deltaC.pos = VNULL;
* deltaC_dt.pos = VNULL;
* deltaC_dtdt.pos = VNULL;
* deltaC.rot = QUNIT;
* deltaC_dt.rot = QNULL;
* deltaC_dtdt.rot = QNULL;
*/
// if (dist_funct.Get_Type() != ChFunction.FunctionType.FUNCT_RECORDER)
// dist_funct = new ChFunction_Recorder();
// record point
double rec_dist = ChVector.Vlength(ChVector.Vsub(marker1.GetAbsCoord().pos, marker2.GetAbsCoord().pos));
rec_dist -= offset;
// (ChFunction_Recorder)(dist_funct).AddPoint(mytime, rec_dist, 1); // (x,y,w) x=t
}
// Move (well, rotate...) marker 2 to align it in actuator direction
// ! 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);
// ChMatrix33<double> ma = new ChMatrix33<double>(0);
ma.Set_A_quaternion(marker2.GetAbsCoord().rot);
ChVector absdist = ChVector.Vsub(marker1.GetAbsCoord().pos, marker2.GetAbsCoord().pos);
ChVector mx = ChVector.Vnorm(absdist);
ChVector my = ma.Get_A_Yaxis();
if (ChVector.Vequal(mx, my))
{
if (mx.x == 1.0)
{
my = ChVector.VECT_Y;
}
else
{
my = ChVector.VECT_X;
}
}
ChVector mz = ChVector.Vnorm(ChVector.Vcross(mx, my));
my = ChVector.Vnorm(ChVector.Vcross(mz, mx));
ma.Set_A_axis(mx, my, mz);
ChCoordsys newmarkpos;
ChVector oldpos = marker2.FrameMoving.GetPos(); // backup to avoid numerical err.accumulation
newmarkpos.pos = marker2.GetAbsCoord().pos;
newmarkpos.rot = ma.Get_A_quaternion();
marker2.Impose_Abs_Coord(newmarkpos); // rotate "main" marker2 into tangent position (may add err.accumulation)
marker2.FrameMoving.SetPos(oldpos); // backup to avoid numerical err.accumulation
if (learn)
{
return; // no need to go on further...--.>>>
}
// imposed relative positions/speeds
deltaC.pos = ChVector.VNULL;
deltaC.pos.x = dist_funct.Get_y(ChTime) + offset; // distance is always on M2 'X' axis
deltaC_dt.pos = ChVector.VNULL;
deltaC_dt.pos.x = dist_funct.Get_y_dx(ChTime); // distance speed
deltaC_dtdt.pos = ChVector.VNULL;
deltaC_dtdt.pos.x = dist_funct.Get_y_dxdx(ChTime); // distance acceleration
// add also the centripetal acceleration if distance vector's rotating,
// as centripetal acc. of point sliding on a sphere surface.
ChVector tang_speed = GetRelM_dt().pos;
tang_speed.x = 0; // only z-y coords in relative tang speed vector
double len_absdist = ChVector.Vlength(absdist); // don't divide by zero
if (len_absdist > 1E-6)
{
deltaC_dtdt.pos.x -= Math.Pow(ChVector.Vlength(tang_speed), 2) / ChVector.Vlength(absdist); // An = Adelta -(Vt^2 / r)
}
deltaC.rot = ChQuaternion.QUNIT; // no relative rotations imposed!
deltaC_dt.rot = ChQuaternion.QNULL;
deltaC_dtdt.rot = ChQuaternion.QNULL;
// Compute motor variables
// double m_rotation;
// double m_torque;
mot_rerot = (deltaC.pos.x - offset) / mot_tau;
mot_rerot_dt = deltaC_dt.pos.x / mot_tau;
mot_rerot_dtdt = deltaC_dtdt.pos.x / mot_tau;
mot_retorque = mot_rerot_dtdt * mot_inertia + (react_force.x * mot_tau) / mot_eta;
// m_rotation = (deltaC.pos.x() - offset) / mot_tau;
// m_torque = (deltaC_dtdt.pos.x() / mot_tau) * mot_inertia + (react_force.x() * mot_tau) / mot_eta;
if (learn_torque_rotation)
{
// if (mot_torque.Get_Type() != ChFunction.FunctionType.FUNCT_RECORDER)
// mot_torque = new ChFunction_Recorder();
// if (mot_rot.Get_Type() != ChFunction.FunctionType.FUNCT_RECORDER)
// mot_rot = new ChFunction_Recorder();
// std::static_pointer_cast<ChFunction_Recorder>(mot_torque).AddPoint(mytime, mot_retorque, 1); // (x,y,w) x=t
// std::static_pointer_cast<ChFunction_Recorder>(mot_rot).AddPoint(mytime, mot_rerot, 1); // (x,y,w) x=t
}
}
// 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;
}
