TetrahedralCorotationalFEMForceField

Corotational FEM Tetrahedral finite elements

Templates:

• Vec3d

Target: Sofa.Component.SolidMechanics.FEM.Elastic

namespace: sofa::component::solidmechanics::fem::elastic

parents:

• ForceField

Data:

Name	Description	Default value
name	object name	unnamed
printLog	if true, emits extra messages at runtime.	0
tags	list of the subsets the objet belongs to
bbox	this object bounding box
componentState	The state of the component among (Dirty, Valid, Undefined, Loading, Invalid).	Undefined
listening	if true, handle the events, otherwise ignore the events	0
isCompliance	Consider the component as a compliance, else as a stiffness	0
rayleighStiffness	Rayleigh damping - stiffness matrix coefficient	0
tetrahedronInfo	Internal tetrahedron data
method	"small", "large" (by QR) or "polar" displacements	large
poissonRatio	FEM Poisson Ratio	0.45
youngModulus	FEM Young Modulus	5000
localStiffnessFactor	Allow specification of different stiffness per element. If there are N element and M values are specified, the youngModulus factor for element i would be localStiffnessFactor[i*M/N]
updateStiffnessMatrix		0
computeGlobalMatrix		0
Visualization
drawing	draw the forcefield if true	1
drawColor1	draw color for faces 1	0 0 1 1
drawColor2	draw color for faces 2	0 0.5 1 1
drawColor3	draw color for faces 3	0 1 1 1
drawColor4	draw color for faces 4	0.5 1 1 1

Links:

Name	Description
context	Graph Node containing this object (or BaseContext::getDefault() if no graph is used)
slaves	Sub-objects used internally by this object
master	nullptr for regular objects, or master object for which this object is one sub-objects
mechanicalStates	List of mechanical states to which this component is associated
mstate	MechanicalState used by this component
topology	link to the topology container

Examples

Component/SolidMechanics/FEM/TetrahedralCorotationalFEMForceField.scn

XMLPython

<?xml version="1.0" ?>
<!-- Mechanical Tetrahedral Corotational FEM Basic Example -->
<Node name="root" dt="0.05" showBoundingTree="0" gravity="0 -9 0">
    <RequiredPlugin name="Sofa.Component.Collision.Detection.Algorithm"/> <!-- Needed to use components [BVHNarrowPhase BruteForceBroadPhase CollisionPipeline] -->
    <RequiredPlugin name="Sofa.Component.Collision.Detection.Intersection"/> <!-- Needed to use components [MinProximityIntersection] -->
    <RequiredPlugin name="Sofa.Component.Collision.Response.Contact"/> <!-- Needed to use components [CollisionResponse] -->
    <RequiredPlugin name="Sofa.Component.Constraint.Projective"/> <!-- Needed to use components [FixedProjectiveConstraint] -->
    <RequiredPlugin name="Sofa.Component.Engine.Select"/> <!-- Needed to use components [BoxROI] -->
    <RequiredPlugin name="Sofa.Component.LinearSolver.Iterative"/> <!-- Needed to use components [CGLinearSolver] -->
    <RequiredPlugin name="Sofa.Component.Mass"/> <!-- Needed to use components [DiagonalMass] -->
    <RequiredPlugin name="Sofa.Component.ODESolver.Backward"/> <!-- Needed to use components [EulerImplicitSolver] -->
    <RequiredPlugin name="Sofa.Component.SolidMechanics.FEM.Elastic"/> <!-- Needed to use components [TetrahedralCorotationalFEMForceField] -->
    <RequiredPlugin name="Sofa.Component.StateContainer"/> <!-- Needed to use components [MechanicalObject] -->
    <RequiredPlugin name="Sofa.Component.Topology.Container.Dynamic"/> <!-- Needed to use components [TetrahedronSetGeometryAlgorithms TetrahedronSetTopologyContainer TetrahedronSetTopologyModifier] -->
    <RequiredPlugin name="Sofa.Component.Topology.Container.Grid"/> <!-- Needed to use components [RegularGridTopology] -->
    <RequiredPlugin name="Sofa.Component.Topology.Mapping"/> <!-- Needed to use components [Hexa2TetraTopologicalMapping] -->
    <RequiredPlugin name="Sofa.Component.Visual"/> <!-- Needed to use components [VisualStyle] -->

    <VisualStyle displayFlags="showBehaviorModels showForceFields" />
    <CollisionPipeline verbose="0" />
    <CollisionResponse />
    <BruteForceBroadPhase/>
    <BVHNarrowPhase/>
    <MinProximityIntersection name="Proximity" alarmDistance="0.8" contactDistance="0.5" />
    <DefaultAnimationLoop/>

    <Node name="BeamFEM_SMALL">
        <EulerImplicitSolver name="cg_odesolver" printLog="false"  rayleighStiffness="0.1" rayleighMass="0.1" />
        <CGLinearSolver iterations="25" name="linear solver" tolerance="1.0e-9" threshold="1.0e-9" />

        <RegularGridTopology name="grid" min="-5 -5 0" max="5 5 40" n="5 5 20"/>
        <MechanicalObject template="Vec3" />

        <TetrahedronSetTopologyContainer name="Tetra_topo"/>
        <TetrahedronSetTopologyModifier name="Modifier" />
        <TetrahedronSetGeometryAlgorithms template="Vec3" name="GeomAlgo" />
        <Hexa2TetraTopologicalMapping input="@grid" output="@Tetra_topo" />

        <DiagonalMass massDensity="0.2" />
        <TetrahedralCorotationalFEMForceField name="CFEM" youngModulus="1000" poissonRatio="0.3" method="small" />

        <BoxROI template="Vec3" name="box_roi" box="-6 -6 -1 30 6 0.1" drawBoxes="1" />
        <FixedProjectiveConstraint template="Vec3" indices="@box_roi.indices" />
    </Node>

    <Node name="BeamFEM_LARGE">
        <EulerImplicitSolver name="cg_odesolver" printLog="false"  rayleighStiffness="0.1" rayleighMass="0.1" />
        <CGLinearSolver iterations="25" name="linear solver" tolerance="1.0e-9" threshold="1.0e-9" />

        <RegularGridTopology name="grid" min="-5 -5 0" max="5 5 40" n="5 5 20"/>
        <MechanicalObject template="Vec3" translation="11 0 0"/>

        <TetrahedronSetTopologyContainer name="Tetra_topo" />
        <TetrahedronSetTopologyModifier name="Modifier" />
        <TetrahedronSetGeometryAlgorithms template="Vec3" name="GeomAlgo" />
        <Hexa2TetraTopologicalMapping input="@grid" output="@Tetra_topo" />

        <DiagonalMass massDensity="0.2" />
        <TetrahedralCorotationalFEMForceField name="CFEM" youngModulus="1000" poissonRatio="0.3" method="large" />

        <BoxROI template="Vec3" name="box_roi" box="-6 -6 -1 30 6 0.1" drawBoxes="1" />
        <FixedProjectiveConstraint template="Vec3" indices="@box_roi.indices" />
    </Node>

    <Node name="BeamFEM_POLAR">
        <EulerImplicitSolver name="cg_odesolver" printLog="false"  rayleighStiffness="0.1" rayleighMass="0.1" />
        <CGLinearSolver iterations="25" name="linear solver" tolerance="1.0e-9" threshold="1.0e-9" />

        <RegularGridTopology name="grid" min="-5 -5 0" max="5 5 40" n="5 5 20"/>
        <MechanicalObject template="Vec3" translation="22 0 0"/>

        <TetrahedronSetTopologyContainer name="Tetra_topo"/>
        <TetrahedronSetTopologyModifier name="Modifier" />
        <TetrahedronSetGeometryAlgorithms template="Vec3" name="GeomAlgo" />
        <Hexa2TetraTopologicalMapping input="@grid" output="@Tetra_topo" />

        <DiagonalMass massDensity="0.2" />
        <TetrahedralCorotationalFEMForceField name="CFEM" youngModulus="1000" poissonRatio="0.3" method="polar" />

        <BoxROI template="Vec3" name="box_roi" box="-6 -6 -1 30 6 0.1" drawBoxes="1" />
        <FixedProjectiveConstraint template="Vec3" indices="@box_roi.indices" />
    </Node>


</Node>

def createScene(rootNode):

    root = rootNode.addChild('root', dt="0.05", showBoundingTree="0", gravity="0 -9 0")
    root.addObject('RequiredPlugin', name="Sofa.Component.Collision.Detection.Algorithm")
    root.addObject('RequiredPlugin', name="Sofa.Component.Collision.Detection.Intersection")
    root.addObject('RequiredPlugin', name="Sofa.Component.Collision.Response.Contact")
    root.addObject('RequiredPlugin', name="Sofa.Component.Constraint.Projective")
    root.addObject('RequiredPlugin', name="Sofa.Component.Engine.Select")
    root.addObject('RequiredPlugin', name="Sofa.Component.LinearSolver.Iterative")
    root.addObject('RequiredPlugin', name="Sofa.Component.Mass")
    root.addObject('RequiredPlugin', name="Sofa.Component.ODESolver.Backward")
    root.addObject('RequiredPlugin', name="Sofa.Component.SolidMechanics.FEM.Elastic")
    root.addObject('RequiredPlugin', name="Sofa.Component.StateContainer")
    root.addObject('RequiredPlugin', name="Sofa.Component.Topology.Container.Dynamic")
    root.addObject('RequiredPlugin', name="Sofa.Component.Topology.Container.Grid")
    root.addObject('RequiredPlugin', name="Sofa.Component.Topology.Mapping")
    root.addObject('RequiredPlugin', name="Sofa.Component.Visual")
    root.addObject('VisualStyle', displayFlags="showBehaviorModels showForceFields")
    root.addObject('CollisionPipeline', verbose="0")
    root.addObject('CollisionResponse')
    root.addObject('BruteForceBroadPhase')
    root.addObject('BVHNarrowPhase')
    root.addObject('MinProximityIntersection', name="Proximity", alarmDistance="0.8", contactDistance="0.5")
    root.addObject('DefaultAnimationLoop')

    BeamFEM_SMALL = root.addChild('BeamFEM_SMALL')
    BeamFEM_SMALL.addObject('EulerImplicitSolver', name="cg_odesolver", printLog="false", rayleighStiffness="0.1", rayleighMass="0.1")
    BeamFEM_SMALL.addObject('CGLinearSolver', iterations="25", name="linear solver", tolerance="1.0e-9", threshold="1.0e-9")
    BeamFEM_SMALL.addObject('RegularGridTopology', name="grid", min="-5 -5 0", max="5 5 40", n="5 5 20")
    BeamFEM_SMALL.addObject('MechanicalObject', template="Vec3")
    BeamFEM_SMALL.addObject('TetrahedronSetTopologyContainer', name="Tetra_topo")
    BeamFEM_SMALL.addObject('TetrahedronSetTopologyModifier', name="Modifier")
    BeamFEM_SMALL.addObject('TetrahedronSetGeometryAlgorithms', template="Vec3", name="GeomAlgo")
    BeamFEM_SMALL.addObject('Hexa2TetraTopologicalMapping', input="@grid", output="@Tetra_topo")
    BeamFEM_SMALL.addObject('DiagonalMass', massDensity="0.2")
    BeamFEM_SMALL.addObject('TetrahedralCorotationalFEMForceField', name="CFEM", youngModulus="1000", poissonRatio="0.3", method="small")
    BeamFEM_SMALL.addObject('BoxROI', template="Vec3", name="box_roi", box="-6 -6 -1 30 6 0.1", drawBoxes="1")
    BeamFEM_SMALL.addObject('FixedProjectiveConstraint', template="Vec3", indices="@box_roi.indices")

    BeamFEM_LARGE = root.addChild('BeamFEM_LARGE')
    BeamFEM_LARGE.addObject('EulerImplicitSolver', name="cg_odesolver", printLog="false", rayleighStiffness="0.1", rayleighMass="0.1")
    BeamFEM_LARGE.addObject('CGLinearSolver', iterations="25", name="linear solver", tolerance="1.0e-9", threshold="1.0e-9")
    BeamFEM_LARGE.addObject('RegularGridTopology', name="grid", min="-5 -5 0", max="5 5 40", n="5 5 20")
    BeamFEM_LARGE.addObject('MechanicalObject', template="Vec3", translation="11 0 0")
    BeamFEM_LARGE.addObject('TetrahedronSetTopologyContainer', name="Tetra_topo")
    BeamFEM_LARGE.addObject('TetrahedronSetTopologyModifier', name="Modifier")
    BeamFEM_LARGE.addObject('TetrahedronSetGeometryAlgorithms', template="Vec3", name="GeomAlgo")
    BeamFEM_LARGE.addObject('Hexa2TetraTopologicalMapping', input="@grid", output="@Tetra_topo")
    BeamFEM_LARGE.addObject('DiagonalMass', massDensity="0.2")
    BeamFEM_LARGE.addObject('TetrahedralCorotationalFEMForceField', name="CFEM", youngModulus="1000", poissonRatio="0.3", method="large")
    BeamFEM_LARGE.addObject('BoxROI', template="Vec3", name="box_roi", box="-6 -6 -1 30 6 0.1", drawBoxes="1")
    BeamFEM_LARGE.addObject('FixedProjectiveConstraint', template="Vec3", indices="@box_roi.indices")

    BeamFEM_POLAR = root.addChild('BeamFEM_POLAR')
    BeamFEM_POLAR.addObject('EulerImplicitSolver', name="cg_odesolver", printLog="false", rayleighStiffness="0.1", rayleighMass="0.1")
    BeamFEM_POLAR.addObject('CGLinearSolver', iterations="25", name="linear solver", tolerance="1.0e-9", threshold="1.0e-9")
    BeamFEM_POLAR.addObject('RegularGridTopology', name="grid", min="-5 -5 0", max="5 5 40", n="5 5 20")
    BeamFEM_POLAR.addObject('MechanicalObject', template="Vec3", translation="22 0 0")
    BeamFEM_POLAR.addObject('TetrahedronSetTopologyContainer', name="Tetra_topo")
    BeamFEM_POLAR.addObject('TetrahedronSetTopologyModifier', name="Modifier")
    BeamFEM_POLAR.addObject('TetrahedronSetGeometryAlgorithms', template="Vec3", name="GeomAlgo")
    BeamFEM_POLAR.addObject('Hexa2TetraTopologicalMapping', input="@grid", output="@Tetra_topo")
    BeamFEM_POLAR.addObject('DiagonalMass', massDensity="0.2")
    BeamFEM_POLAR.addObject('TetrahedralCorotationalFEMForceField', name="CFEM", youngModulus="1000", poissonRatio="0.3", method="polar")
    BeamFEM_POLAR.addObject('BoxROI', template="Vec3", name="box_roi", box="-6 -6 -1 30 6 0.1", drawBoxes="1")
    BeamFEM_POLAR.addObject('FixedProjectiveConstraint', template="Vec3", indices="@box_roi.indices")