rigidBodyDynamics/restraints: Added linearDamper

src/rigidBodyDynamics/Make/files

@@ -28,6 +28,7 @@ joints/Pxyz/Pxyz.C
 restraints/restraint/rigidBodyRestraint.C
 restraints/restraint/rigidBodyRestraintNew.C
 restraints/linearSpring/linearSpring.C
+restraints/linearDamper/linearDamper.C
 
 rigidBodyModel/rigidBodyModel.C
 rigidBodyModel/forwardDynamics.C

src/rigidBodyDynamics/restraints/linearDamper/linearDamper.C

@@ -0,0 +1,112 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2013-2015 OpenFOAM Foundation
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM.
+
+    OpenFOAM is free software: you can redistribute it and/or modify it
+    under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+    for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
+
+\*---------------------------------------------------------------------------*/
+
+#include "linearDamper.H"
+#include "rigidBodyModel.H"
+#include "addToRunTimeSelectionTable.H"
+
+// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
+
+namespace Foam
+{
+namespace RBD
+{
+namespace restraints
+{
+    defineTypeNameAndDebug(linearDamper, 0);
+
+    addToRunTimeSelectionTable
+    (
+        restraint,
+        linearDamper,
+        dictionary
+    );
+}
+}
+}
+
+
+// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
+
+Foam::RBD::restraints::linearDamper::linearDamper
+(
+    const word& name,
+    const dictionary& dict,
+    const rigidBodyModel& model
+)
+:
+    restraint(name, dict, model)
+{
+    read(dict);
+}
+
+
+// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
+
+Foam::RBD::restraints::linearDamper::~linearDamper()
+{}
+
+
+// * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * * //
+
+Foam::spatialVector Foam::RBD::restraints::linearDamper::restrain() const
+{
+    vector force = -coeff_*model_.v(model_.master(bodyID_)).l();
+
+    if (model_.debug)
+    {
+        Info<< " force " << force << endl;
+    }
+
+    return spatialVector(Zero, force);
+}
+
+
+bool Foam::RBD::restraints::linearDamper::read
+(
+    const dictionary& dict
+)
+{
+    restraint::read(dict);
+
+    coeffs_.lookup("coeff") >> coeff_;
+
+    return true;
+}
+
+
+void Foam::RBD::restraints::linearDamper::write
+(
+    Ostream& os
+) const
+{
+    restraint::write(os);
+
+    os.writeKeyword("coeff")
+        << coeff_ << token::END_STATEMENT << nl;
+}
+
+
+// ************************************************************************* //

src/rigidBodyDynamics/restraints/linearDamper/linearDamper.H

@@ -0,0 +1,116 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2016 OpenFOAM Foundation
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM.
+
+    OpenFOAM is free software: you can redistribute it and/or modify it
+    under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+    for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
+
+Class
+    Foam::RBD::restraints::linearDamper
+
+Description
+    Linear damper restraint.  Operates in the local frame of the body.
+
+SourceFiles
+    linearDamper.C
+
+\*---------------------------------------------------------------------------*/
+
+#ifndef RBD_restraints_linearDamper_H
+#define RBD_restraints_linearDamper_H
+
+#include "rigidBodyRestraint.H"
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+namespace Foam
+{
+namespace RBD
+{
+namespace restraints
+{
+
+/*---------------------------------------------------------------------------*\
+                          Class linearDamper Declaration
+\*---------------------------------------------------------------------------*/
+
+class linearDamper
+:
+    public restraint
+{
+    // Private data
+
+        //- Damping coefficient [Ns/m]
+        scalar coeff_;
+
+
+public:
+
+    //- Runtime type information
+    TypeName("linearDamper");
+
+
+    // Constructors
+
+        //- Construct from components
+        linearDamper
+        (
+            const word& name,
+            const dictionary& dict,
+            const rigidBodyModel& model
+        );
+
+        //- Construct and return a clone
+        virtual autoPtr<restraint> clone() const
+        {
+            return autoPtr<restraint>
+            (
+                new linearDamper(*this)
+            );
+        }
+
+
+    //- Destructor
+    virtual ~linearDamper();
+
+
+    // Member Functions
+
+        //- Return the external force applied to the body by this restraint
+        virtual spatialVector restrain() const;
+
+        //- Update properties from given dictionary
+        virtual bool read(const dictionary& dict);
+
+        //- Write
+        virtual void write(Ostream&) const;
+};
+
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+} // End namespace restraints
+} // End namespace RBD
+} // End namespace Foam
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#endif
+
+// ************************************************************************* //

src/rigidBodyDynamics/restraints/linearSpring/linearSpring.C

@@ -57,12 +57,7 @@ Foam::RBD::restraints::linearSpring::linearSpring
     const rigidBodyModel& model
 )
 :
-    restraint(name, dict, model),
-    anchor_(),
-    refAttachmentPt_(),
-    stiffness_(),
-    damping_(),
-    restLength_()
+    restraint(name, dict, model)
 {
     read(dict);
 }
@@ -88,9 +83,16 @@ Foam::spatialVector Foam::RBD::restraints::linearSpring::restrain() const
     // Velocity of the attached end of the spring
     vector v = bodyPointVelocity(refAttachmentPt_).l();
 
-    // Force and moment including optional damping
-    vector force = (-stiffness_*(magR - restLength_) - damping_*(r & v))*r;
-    vector moment = (attachmentPt - model_.X0(bodyIndex_).r()) ^ force;
+    // Force and moment on the master body including optional damping
+    vector force
+    (
+        (-stiffness_*(magR - restLength_) - damping_*(r & v))*r
+    );
+
+    vector moment
+    (
+        (attachmentPt - model_.X0(model_.master(bodyID_)).r()) ^ force
+    );
 
     if (model_.debug)
     {

src/rigidBodyDynamics/restraints/linearSpring/linearSpring.H

@@ -63,10 +63,10 @@ class linearSpring
         //- Reference point of attachment to the solid body
         point refAttachmentPt_;
 
-        //- Spring stiffness coefficient (N/m)
+        //- Spring stiffness coefficient [N/m]
         scalar stiffness_;
 
-        //- Damping coefficient (Ns/m)
+        //- Damping coefficient [Ns/m]
         scalar damping_;
 
         //- Rest length - length of spring when no forces are applied to it

src/rigidBodyDynamics/restraints/restraint/rigidBodyRestraint.C

@@ -48,7 +48,7 @@ Foam::RBD::restraint::restraint
 )
 :
     name_(name),
-    bodyIndex_(model.bodyID(dict.lookup("body"))),
+    bodyID_(model.bodyID(dict.lookup("body"))),
     coeffs_(dict),
     model_(model)
 {}
@@ -80,7 +80,7 @@ void Foam::RBD::restraint::write(Ostream& os) const
     os.writeKeyword("type")
         << type() << token::END_STATEMENT << nl;
     os.writeKeyword("body")
-        << model_.name(bodyIndex_) << token::END_STATEMENT << nl;
+        << model_.name(bodyID_) << token::END_STATEMENT << nl;
 }
 
 

src/rigidBodyDynamics/restraints/restraint/rigidBodyRestraint.H

@@ -72,8 +72,8 @@ protected:
         //- Name of the restraint
         word name_;
 
-        //- Index of the body the restraint is applied to
-        label bodyIndex_;
+        //- ID of the body the restraint is applied to
+        label bodyID_;
 
         //- Restraint model specific coefficient dictionary
         dictionary coeffs_;
@@ -148,9 +148,9 @@ public:
             return name_;
         }
 
-        label bodyIndex() const
+        label bodyID() const
         {
-            return bodyIndex_;
+            return bodyID_;
         }
 
         //- Return the external force applied to the body by this restraint

src/rigidBodyDynamics/restraints/restraint/rigidBodyRestraintI.H

@@ -32,7 +32,7 @@ inline Foam::point Foam::RBD::restraint::bodyPoint
     const point& p
 ) const
 {
-    return (model_.X0(bodyIndex_).inv() && spatialVector(Zero, p)).l();
+    return (model_.X0(bodyID_).inv() && spatialVector(Zero, p)).l();
 }
 
 
@@ -41,7 +41,7 @@ inline Foam::spatialVector Foam::RBD::restraint::bodyPointVelocity
     const point& p
 ) const
 {
-    return model_.v(bodyIndex_, p);
+    return model_.v(bodyID_, p);
 }
 
 

src/rigidBodyDynamics/rigidBodyModel/forwardDynamics.C

@@ -40,7 +40,7 @@ void Foam::RBD::rigidBodyModel::applyRestraints(Field<spatialVector>& fx) const
         DebugInfo << "Restraint " << restraints_[ri].name();
 
         // Accumulate the restraint forces
-        fx[restraints_[ri].bodyIndex()] += restraints_[ri].restrain();
+        fx[master(restraints_[ri].bodyID())] += restraints_[ri].restrain();
     }
 }
 

src/rigidBodyDynamics/rigidBodyModel/rigidBodyModel.C

@@ -162,6 +162,12 @@ Foam::RBD::rigidBodyModel::rigidBodyModel(const dictionary& dict)
 }
 
 
+// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
+
+Foam::RBD::rigidBodyModel::~rigidBodyModel()
+{}
+
+
 // * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * * //
 
 Foam::label Foam::RBD::rigidBodyModel::join_

src/rigidBodyDynamics/rigidBodyModel/rigidBodyModel.H

@@ -89,7 +89,6 @@ class rigidBodyModel
         //- Add restraints to the motion
         void addRestraints(const dictionary& dict);
 
-
 protected:
 
     // Protected data representing the model structure
@@ -220,8 +219,7 @@ public:
 
 
     //- Destructor
-    virtual ~rigidBodyModel()
-    {}
+    virtual ~rigidBodyModel();
 
 
     // Member Functions
@@ -261,6 +259,9 @@ public:
         //- Return the inertia of body i
         inline const rigidBodyInertia& I(const label i) const;
 
+        //- Return the spatial velocity of the bodies
+        inline const spatialVector& v(const label i) const;
+
         //- Join the given body to the parent with ID parentID via the given
         //  joint with transform from the parent frame to the joint frame XT.
         virtual label join

src/rigidBodyDynamics/rigidBodyModel/rigidBodyModelI.H

@@ -99,6 +99,13 @@ Foam::RBD::rigidBodyModel::I(const label i) const
 }
 
 
+inline const Foam::spatialVector&
+Foam::RBD::rigidBodyModel::v(const label i) const
+{
+    return v_[i];
+}
+
+
 inline bool Foam::RBD::rigidBodyModel::merged(label bodyID) const
 {
     return bodyID < 0;