TriangularBendingSprings

Springs added to a triangular mesh to prevent bending

Vec3d

Templates:

• Vec3d

Target: Sofa.Component.SolidMechanics.Spring

namespace: sofa::component::solidmechanics::spring

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
rayleighStiffness	Rayleigh damping - stiffness matrix coefficient	0
stiffness	uniform stiffness for the all springs	100000
damping	uniform damping for the all springs	1
edgeInfo	Internal edge data
Visualization
showSprings	option to draw springs	1

Links

Name	Description	Destination type name
context	Graph Node containing this object (or BaseContext::getDefault() if no graph is used)	BaseContext
slaves	Sub-objects used internally by this object	BaseObject
master	nullptr for regular objects, or master object for which this object is one sub-objects	BaseObject
mechanicalStates	List of mechanical states to which this component is associated	BaseMechanicalState
mstate	MechanicalState used by this component	MechanicalState<Vec3d>
topology	link to the topology container	BaseMeshTopology

Examples

TriangularBendingSprings.scn

XMLPython

<!-- Mechanical MassSpring Group Basic Example -->
<Node name="root" dt="0.005" showBoundingTree="0" gravity="0 -90 10">
    <Node name="plugins">
        <RequiredPlugin name="Sofa.Component.Constraint.Projective"/> <!-- Needed to use components [FixedProjectiveConstraint] -->
        <RequiredPlugin name="Sofa.Component.IO.Mesh"/> <!-- Needed to use components [MeshGmshLoader] -->
        <RequiredPlugin name="Sofa.Component.LinearSolver.Direct"/> <!-- Needed to use components [AsyncSparseLDLSolver] -->
        <RequiredPlugin name="Sofa.Component.LinearSolver.Iterative"/> <!-- Needed to use components [ShewchukPCGLinearSolver] -->
        <RequiredPlugin name="Sofa.Component.Mapping.Linear"/> <!-- Needed to use components [IdentityMapping] -->
        <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 [TriangularFEMForceField] -->
        <RequiredPlugin name="Sofa.Component.SolidMechanics.Spring"/> <!-- Needed to use components [TriangularBendingSprings] -->
        <RequiredPlugin name="Sofa.Component.StateContainer"/> <!-- Needed to use components [MechanicalObject] -->
        <RequiredPlugin name="Sofa.Component.Topology.Container.Dynamic"/> <!-- Needed to use components [TriangleSetTopologyContainer] -->
        <RequiredPlugin name="Sofa.Component.Visual"/> <!-- Needed to use components [VisualStyle] -->
        <RequiredPlugin name="Sofa.GL.Component.Rendering3D"/> <!-- Needed to use components [OglModel] -->
    </Node>
    <VisualStyle displayFlags="showBehaviorModels" />
    <DefaultAnimationLoop/>

    <Node name="SquareGravity">
        <EulerImplicitSolver name="cg_odesolver" printLog="false"  rayleighStiffness="0.1" rayleighMass="0.1" />
        <ShewchukPCGLinearSolver preconditioner="@preconditioner"/>
        <AsyncSparseLDLSolver name="preconditioner" template="CompressedRowSparseMatrixMat3x3"/>
        <MeshGmshLoader name="loader" filename="mesh/square3.msh" createSubelements="true"/>
        <MechanicalObject src="@loader" scale="10" />
        <TriangleSetTopologyContainer name="Container" triangles="@loader.triangles"/>
        <DiagonalMass massDensity="0.015" />
        <FixedProjectiveConstraint indices="0 1" />
        <TriangularFEMForceField name="FEM" youngModulus="60" poissonRatio="0.3" method="large" />
        <TriangularBendingSprings name="BS" stiffness="300" damping="1.0" />
        <Node >
            <OglModel name="Visual" color="yellow" />
            <IdentityMapping input="@.." output="@Visual" />
        </Node>
    </Node>
</Node>

def createScene(root_node):

   root = root_node.addChild('root', dt="0.005", showBoundingTree="0", gravity="0 -90 10")

   plugins = root.addChild('plugins')

   plugins.addObject('RequiredPlugin', name="Sofa.Component.Constraint.Projective")
   plugins.addObject('RequiredPlugin', name="Sofa.Component.IO.Mesh")
   plugins.addObject('RequiredPlugin', name="Sofa.Component.LinearSolver.Direct")
   plugins.addObject('RequiredPlugin', name="Sofa.Component.LinearSolver.Iterative")
   plugins.addObject('RequiredPlugin', name="Sofa.Component.Mapping.Linear")
   plugins.addObject('RequiredPlugin', name="Sofa.Component.Mass")
   plugins.addObject('RequiredPlugin', name="Sofa.Component.ODESolver.Backward")
   plugins.addObject('RequiredPlugin', name="Sofa.Component.SolidMechanics.FEM.Elastic")
   plugins.addObject('RequiredPlugin', name="Sofa.Component.SolidMechanics.Spring")
   plugins.addObject('RequiredPlugin', name="Sofa.Component.StateContainer")
   plugins.addObject('RequiredPlugin', name="Sofa.Component.Topology.Container.Dynamic")
   plugins.addObject('RequiredPlugin', name="Sofa.Component.Visual")
   plugins.addObject('RequiredPlugin', name="Sofa.GL.Component.Rendering3D")

   root.addObject('VisualStyle', displayFlags="showBehaviorModels")
   root.addObject('DefaultAnimationLoop', )

   square_gravity = root.addChild('SquareGravity')

   square_gravity.addObject('EulerImplicitSolver', name="cg_odesolver", printLog="false", rayleighStiffness="0.1", rayleighMass="0.1")
   square_gravity.addObject('ShewchukPCGLinearSolver', preconditioner="@preconditioner")
   square_gravity.addObject('AsyncSparseLDLSolver', name="preconditioner", template="CompressedRowSparseMatrixMat3x3")
   square_gravity.addObject('MeshGmshLoader', name="loader", filename="mesh/square3.msh", createSubelements="true")
   square_gravity.addObject('MechanicalObject', src="@loader", scale="10")
   square_gravity.addObject('TriangleSetTopologyContainer', name="Container", triangles="@loader.triangles")
   square_gravity.addObject('DiagonalMass', massDensity="0.015")
   square_gravity.addObject('FixedProjectiveConstraint', indices="0 1")
   square_gravity.addObject('TriangularFEMForceField', name="FEM", youngModulus="60", poissonRatio="0.3", method="large")
   square_gravity.addObject('TriangularBendingSprings', name="BS", stiffness="300", damping="1.0")

   node = SquareGravity.addChild('node')

   node.addObject('OglModel', name="Visual", color="yellow")
   node.addObject('IdentityMapping', input="@..", output="@Visual")

TriangularBendingSprings_RemovingMeshTest.scn

XMLPython

<?xml version="1.0" ?>
<!-- Automatic Triangle removal on a simple Triangle topology with FEM: Element removed are define in: ./RemovingTrianglesProcess.txt -->
<Node name="root" gravity="0 -9 0" dt="0.01" bbox="-1 -1 -1 1 1 1">
    <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.IO.Mesh"/> <!-- Needed to use components [MeshGmshLoader] -->
    <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.Spring"/> <!-- Needed to use components [TriangularBendingSprings] -->
    <RequiredPlugin name="Sofa.Component.StateContainer"/> <!-- Needed to use components [MechanicalObject] -->
    <RequiredPlugin name="Sofa.Component.Topology.Container.Dynamic"/> <!-- Needed to use components [TriangleSetGeometryAlgorithms TriangleSetTopologyContainer TriangleSetTopologyModifier] -->
    <RequiredPlugin name="Sofa.Component.Topology.Utility"/> <!-- Needed to use components [TopologicalChangeProcessor] -->
    <RequiredPlugin name="Sofa.Component.Visual"/> <!-- Needed to use components [VisualStyle] -->

    <VisualStyle displayFlags="showVisual showBehaviorModels showForceFields" />
    <DefaultAnimationLoop/>
    <CollisionPipeline verbose="0" />
    <BruteForceBroadPhase name="N2" />
    <BVHNarrowPhase />
    <CollisionResponse response="PenalityContactForceField" />
    <MinProximityIntersection name="Proximity" alarmDistance="0.8" contactDistance="0.5" />
    <Node name="SquareGravity">
        <EulerImplicitSolver name="cg_odesolver" rayleighStiffness="0.1" rayleighMass="0.1" />
        <CGLinearSolver iterations="25" tolerance="1e-5" threshold="1e-5" name="linear solver"/>
        <MeshGmshLoader name="loader" filename="mesh/square3.msh" createSubelements="true" />
        <MechanicalObject name="dofs" src="@loader" template="Vec3" />
        <TriangleSetTopologyContainer name="Triangle_topo" src="@loader"/>
        <TriangleSetTopologyModifier name="Modifier" />
        <TriangleSetGeometryAlgorithms template="Vec3" name="GeomAlgo" />
        <DiagonalMass template="Vec3,Vec3" name="mass" massDensity="1.0" />

        <TriangularBendingSprings template="Vec3" name="FEM-Bend" stiffness="300" damping="1" />

        <TopologicalChangeProcessor listening="1" filename="RemovingTrianglesProcess_constraint.txt" />
    </Node>
</Node>

def createScene(root_node):

   root = root_node.addChild('root', gravity="0 -9 0", dt="0.01", bbox="-1 -1 -1 1 1 1")

   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.IO.Mesh")
   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.Spring")
   root.addObject('RequiredPlugin', name="Sofa.Component.StateContainer")
   root.addObject('RequiredPlugin', name="Sofa.Component.Topology.Container.Dynamic")
   root.addObject('RequiredPlugin', name="Sofa.Component.Topology.Utility")
   root.addObject('RequiredPlugin', name="Sofa.Component.Visual")
   root.addObject('VisualStyle', displayFlags="showVisual showBehaviorModels showForceFields")
   root.addObject('DefaultAnimationLoop', )
   root.addObject('CollisionPipeline', verbose="0")
   root.addObject('BruteForceBroadPhase', name="N2")
   root.addObject('BVHNarrowPhase', )
   root.addObject('CollisionResponse', response="PenalityContactForceField")
   root.addObject('MinProximityIntersection', name="Proximity", alarmDistance="0.8", contactDistance="0.5")

   square_gravity = root.addChild('SquareGravity')

   square_gravity.addObject('EulerImplicitSolver', name="cg_odesolver", rayleighStiffness="0.1", rayleighMass="0.1")
   square_gravity.addObject('CGLinearSolver', iterations="25", tolerance="1e-5", threshold="1e-5", name="linear solver")
   square_gravity.addObject('MeshGmshLoader', name="loader", filename="mesh/square3.msh", createSubelements="true")
   square_gravity.addObject('MechanicalObject', name="dofs", src="@loader", template="Vec3")
   square_gravity.addObject('TriangleSetTopologyContainer', name="Triangle_topo", src="@loader")
   square_gravity.addObject('TriangleSetTopologyModifier', name="Modifier")
   square_gravity.addObject('TriangleSetGeometryAlgorithms', template="Vec3", name="GeomAlgo")
   square_gravity.addObject('DiagonalMass', template="Vec3,Vec3", name="mass", massDensity="1.0")
   square_gravity.addObject('TriangularBendingSprings', template="Vec3", name="FEM-Bend", stiffness="300", damping="1")
   square_gravity.addObject('TopologicalChangeProcessor', listening="1", filename="RemovingTrianglesProcess_constraint.txt")