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Bugfix: Motion constraints in sixDOFqODE. Author: Vuko Vukcevic. Merge: Hrvoje Jasak.

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This commit is contained in:
Hrvoje Jasak 2015-10-29 10:53:54 +00:00
commit 924c76612c
7 changed files with 170 additions and 13 deletions
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8
src/ODE/sixDOF/finiteRotation/finiteRotation.C
View file

@ -1,9 +1,9 @@
/*---------------------------------------------------------------------------*\
========= |
\\ / F ield | foam-extend: Open Source CFD
\\ / O peration | Version: 3.2
\\ / A nd | Web: http://www.foam-extend.org
\\/ M anipulation | For copyright notice see file Copyright
\\ / O peration |
\\ / A nd | For copyright notice see file Copyright
\\/ M anipulation |
-------------------------------------------------------------------------------
License
This file is part of foam-extend.
@ -72,7 +72,7 @@ Foam::scalar Foam::finiteRotation::rotAngle(const tensor& rotT)
Foam::vector Foam::finiteRotation::eulerAngles(const tensor& rotT)
{
// Define a vector containing euler angles (x = roll, y = pitch, z = yaw)
// Create a vector containing euler angles (x = roll, y = pitch, z = yaw)
vector eulerAngles;
scalar& rollAngle = eulerAngles.x();

8
src/ODE/sixDOF/finiteRotation/finiteRotation.H
View file

@ -1,9 +1,9 @@
/*---------------------------------------------------------------------------*\
========= |
\\ / F ield | foam-extend: Open Source CFD
\\ / O peration | Version: 3.2
\\ / A nd | Web: http://www.foam-extend.org
\\/ M anipulation | For copyright notice see file Copyright
\\ / O peration |
\\ / A nd | For copyright notice see file Copyright
\\/ M anipulation |
-------------------------------------------------------------------------------
License
This file is part of foam-extend.
@ -69,7 +69,7 @@ class finiteRotation
//- Calculate rotation angle from given rotation tensor
static scalar rotAngle(const tensor& rotT);
//- Calculate Euler angles (x-y-z (roll-pitch-yaw) convenction) from
//- Calculate Euler angles (x-y-z (roll-pitch-yaw) convention) from
// given rotation tensor. Reference: Mike Day, Insomniac Games,
// Extracting Euler Angles from a Rotation Matrix.
static vector eulerAngles(const tensor& rotT);

121
src/ODE/sixDOF/sixDOFqODE/sixDOFqODE.C
View file

@ -91,12 +91,29 @@ Foam::dimensionedVector Foam::sixDOFqODE::OmegaDot
const dimensionedVector& omega
) const
{
// Fix the global moment for global rotation constraints
dimensionedVector mAbs = moment();
vector& mAbsVal = mAbs.value();
if (fixedRoll_)
{
mAbsVal.x() = 0;
}
if (fixedPitch_)
{
mAbsVal.y() = 0;
}
if (fixedYaw_)
{
mAbsVal.z() = 0;
}
return
inv(momentOfInertia_)
& (
E(omega)
// To relative
+ (rotation.R() & moment())
+ (rotation.R() & mAbs)
+ momentRelative()
);
}
@ -118,11 +135,14 @@ Foam::dimensionedVector Foam::sixDOFqODE::E
Foam::sixDOFqODE::sixDOFqODE(const IOobject& io)
:
IOdictionary(io),
mass_(lookup("mass")),
momentOfInertia_(lookup("momentOfInertia")),
Xequilibrium_(lookup("equilibriumPosition")),
linSpringCoeffs_(lookup("linearSpring")),
linDampingCoeffs_(lookup("linearDamping")),
Xrel_(lookup("Xrel")),
U_(lookup("U")),
Uaverage_(U_),
@ -134,11 +154,20 @@ Foam::sixDOFqODE::sixDOFqODE(const IOobject& io)
omega_(lookup("omega")),
omegaAverage_(omega_),
omegaAverageAbsolute_(omega_),
force_(lookup("force")),
moment_(lookup("moment")),
forceRelative_(lookup("forceRelative")),
momentRelative_(lookup("momentRelative")),
coeffs_(13, 0.0)
coeffs_(13, 0.0),
fixedSurge_(lookup("fixedSurge")),
fixedSway_(lookup("fixedSway")),
fixedHeave_(lookup("fixedHeave")),
fixedRoll_(lookup("fixedRoll")),
fixedPitch_(lookup("fixedPitch")),
fixedYaw_(lookup("fixedYaw"))
{
setCoeffs();
}
@ -163,11 +192,14 @@ Foam::sixDOFqODE::sixDOFqODE
IOobject::NO_WRITE
)
),
mass_(sd.mass_.name(), sd.mass_),
momentOfInertia_(sd.momentOfInertia_.name(), sd.momentOfInertia_),
Xequilibrium_(sd.Xequilibrium_.name(), sd.Xequilibrium_),
linSpringCoeffs_(sd.linSpringCoeffs_.name(), sd.linSpringCoeffs_),
linDampingCoeffs_(sd.linDampingCoeffs_.name(), sd.linDampingCoeffs_),
Xrel_(sd.Xrel_.name(), sd.Xrel_),
U_(sd.U_.name(), sd.U_),
Uaverage_(sd.Uaverage_.name(), sd.Uaverage_),
@ -179,11 +211,20 @@ Foam::sixDOFqODE::sixDOFqODE
sd.omegaAverageAbsolute_.name(),
sd.omegaAverageAbsolute_
),
force_(sd.force_.name(), sd.force_),
moment_(sd.moment_.name(), sd.moment_),
forceRelative_(sd.forceRelative_.name(), sd.forceRelative_),
momentRelative_(sd.momentRelative_.name(), sd.momentRelative_),
coeffs_(sd.coeffs_)
coeffs_(sd.coeffs_),
fixedSurge_(sd.fixedSurge_),
fixedSway_(sd.fixedSway_),
fixedHeave_(sd.fixedHeave_),
fixedRoll_(sd.fixedRoll_),
fixedPitch_(sd.fixedPitch_),
fixedYaw_(sd.fixedYaw_)
{}
@ -199,9 +240,11 @@ void Foam::sixDOFqODE::setState(const sixDOFqODE& sd)
{
mass_ = sd.mass_;
momentOfInertia_ = sd.momentOfInertia_;
Xequilibrium_ = sd.Xequilibrium_;
linSpringCoeffs_ = sd.linSpringCoeffs_;
linDampingCoeffs_ = sd.linDampingCoeffs_;
Xrel_ = sd.Xrel_;
U_ = sd.U_;
Uaverage_ = sd.Uaverage_;
@ -209,6 +252,7 @@ void Foam::sixDOFqODE::setState(const sixDOFqODE& sd)
omega_ = sd.omega_;
omegaAverage_ = sd.omegaAverage_;
omegaAverageAbsolute_ = sd.omegaAverageAbsolute_;
force_ = sd.force_;
moment_ = sd.moment_;
forceRelative_ = sd.forceRelative_;
@ -217,6 +261,13 @@ void Foam::sixDOFqODE::setState(const sixDOFqODE& sd)
// Copy ODE coefficients: this carries actual ODE state
// HJ, 23/Mar/2015
coeffs_ = sd.coeffs_;
fixedSurge_ = sd.fixedSurge_;
fixedSway_ = sd.fixedSway_;
fixedHeave_ = sd.fixedHeave_;
fixedRoll_ = sd.fixedRoll_;
fixedPitch_ = sd.fixedPitch_;
fixedYaw_ = sd.fixedYaw_;
}
@ -248,6 +299,23 @@ void Foam::sixDOFqODE::derivatives
dydx[4] = accel.y();
dydx[5] = accel.z();
// Add translational constraints by setting RHS of given components to zero
if (fixedSurge_)
{
dydx[0] = 0; // Surge velocity
dydx[3] = 0; // Surge acceleration
}
if (fixedSway_)
{
dydx[1] = 0; // Sway velocity
dydx[4] = 0; // Sway acceleration
}
if (fixedHeave_)
{
dydx[2] = 0; // Heave velocity
dydx[5] = 0; // Heave acceleration
}
// Set the derivatives for rotation
dimensionedVector curOmega
(
@ -258,7 +326,7 @@ void Foam::sixDOFqODE::derivatives
const vector omegaDot = OmegaDot(curRotation, curOmega).value();
dydx[6] = omegaDot.x();
dydx[6] = omegaDot.x();
dydx[7] = omegaDot.y();
dydx[8] = omegaDot.z();
@ -266,6 +334,20 @@ void Foam::sixDOFqODE::derivatives
dydx[10] = curRotation.eDot(curOmega.value(), 1);
dydx[11] = curRotation.eDot(curOmega.value(), 2);
dydx[12] = curRotation.eDot(curOmega.value(), 3);
// Add rotational constraints by setting RHS of given components to zero
if (fixedRoll_)
{
dydx[10] = 0; // Roll axis (roll quaternion evolution RHS)
}
if (fixedPitch_)
{
dydx[11] = 0; // Pitch axis (pitch quaternion evolution RHS)
}
if (fixedYaw_)
{
dydx[12] = 0; // Yaw axis (yaw quaternion evolution RHS)
}
}
@ -321,7 +403,23 @@ void Foam::sixDOFqODE::update(const scalar delta)
);
omegaAverage_.value() = rotation_.omegaAverage(delta);
omegaAverageAbsolute_.value() = rotation_.omegaAverageAbsolute(delta);
// Calculate and constrain omegaAverageAbsolute appropriately
vector& omegaAverageAbsoluteValue = omegaAverageAbsolute_.value();
omegaAverageAbsoluteValue = rotation_.omegaAverageAbsolute(delta);
if (fixedRoll_)
{
omegaAverageAbsoluteValue.x() = 0;
}
if (fixedPitch_)
{
omegaAverageAbsoluteValue.y() = 0;
}
if (fixedYaw_)
{
omegaAverageAbsoluteValue.z() = 0;
}
}
@ -367,6 +465,19 @@ Foam::Ostream& Foam::operator<<(Ostream& os, const sixDOFqODE& sds)
os.writeKeyword("momentRelative") << tab << sds.momentRelative()
<< token::END_STATEMENT << endl;
os.writeKeyword("fixedSurge") << tab << sds.fixedSurge_ <<
token::END_STATEMENT << endl;
os.writeKeyword("fixedSway") << tab << sds.fixedSway_ <<
token::END_STATEMENT << endl;
os.writeKeyword("fixedHeave") << tab << sds.fixedHeave_ <<
token::END_STATEMENT << endl;
os.writeKeyword("fixedRoll") << tab << sds.fixedRoll_ <<
token::END_STATEMENT << endl;
os.writeKeyword("fixedPitch") << tab << sds.fixedPitch_ <<
token::END_STATEMENT << endl;
os.writeKeyword("fixedYaw") << tab << sds.fixedYaw_ <<
token::END_STATEMENT << endl;
return os;
}

21
src/ODE/sixDOF/sixDOFqODE/sixDOFqODE.H
View file

@ -131,6 +131,27 @@ class sixDOFqODE
scalarField coeffs_;
//- Motion constraints (given as fixed motion components)
//- Fixed surge (x-translation)
Switch fixedSurge_;
//- Fixed sway (y-translation)
Switch fixedSway_;
//- Fixed heave (z-translation)
Switch fixedHeave_;
//- Fixed roll (rotation around x)
Switch fixedRoll_;
//- Fixed pitch (rotation around y)
Switch fixedPitch_;
//- Fixed yaw (rotation around z)
Switch fixedYaw_;
// Private Member Functions
//- Disallow default bitwise copy construct

8
tutorials/basic/sixDOFSolver/sixDOFmotion/0/bodyA
View file

@ -36,4 +36,12 @@ moment m [1 2 -2 0 0 0 0] (0 0 0);
forceRelative fRel [1 1 -2 0 0 0 0] (0 0 0);
momentRelative mRel [1 2 -2 0 0 0 0] (-0.5773502692 -0.5773502692 -0.5773502692);
// Motion constraints
fixedSurge no;
fixedSway no;
fixedHeave no;
fixedRoll no;
fixedPitch no;
fixedYaw no;
// ************************************************************************* //

8
tutorials/basic/sixDOFSolver/sixDOFmotion/0/bodyB
View file

@ -35,4 +35,12 @@ moment m [1 2 -2 0 0 0 0] (0 0 0);
forceRelative fRel [1 1 -2 0 0 0 0] (0 0 0);
momentRelative mRel [1 2 -2 0 0 0 0] (0 0 10);
// Motion constraints
fixedSurge no;
fixedSway no;
fixedHeave no;
fixedRoll no;
fixedPitch no;
fixedYaw no;
// ************************************************************************* //

9
tutorials/basic/sixDOFSolver/springDamper/0/massSpringDamper
View file

@ -35,4 +35,13 @@ moment m [1 2 -2 0 0 0 0] (0 0 0);
forceRelative fRel [1 1 -2 0 0 0 0] (0 0 0);
momentRelative mRel [1 2 -2 0 0 0 0] (0 0 0);
// Motion constraints
fixedSurge no;
fixedSway no;
fixedHeave no;
fixedRoll no;
fixedPitch no;
fixedYaw no;
// ************************************************************************* //