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EulerImplicitIntegrationScheme

Time integrator using implicit backward Euler scheme.

Target: Sofa.Component.IntegrationScheme.Backward

namespace: sofa::component::integrationscheme::backward

parents:

  • VelocityBasedImplicitIntegrationScheme

Data

Name Description Default value
name object name unnamed
printLog if true, emits extra messages at runtime. 0
tags list of the subsets the object 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 coefficient related to stiffness, > 0 0
rayleighMass Rayleigh damping coefficient related to mass, > 0 0
firstOrder Use this ODE to integrate first order ODE. This will replace the dynamic equation from Ma=f(x,v) to Mv=f(x), meaning that the mass component now acts as capacity. 0
computeFinalAcceleration If true the integration scheme will compute the total acceleration of the timestep after updating the positions. If false, the acceleration vector is only a result of an internal computation. 0
impulseBased If true the integration scheme will compute the right-hand-side in term of impulse instead of forces. 0
trapezoidalScheme Boolean to use the trapezoidal scheme instead of the implicit Euler scheme and get second order accuracy in time (false by default) 0
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 BaseComponent
master nullptr for regular objects, or master object for which this object is one sub-objects BaseComponent
linearSolver Linear solver used by this component LinearSolver

Examples

EulerImplicitIntegrationScheme-comparison.scn

<?xml version="1.0"?>
<Node name="root" gravity="-1.8 0 100" dt="0.1">
    <RequiredPlugin pluginName="Sofa.Component.Constraint.Projective"/> <!-- Needed to use components [FixedProjectiveConstraint] -->
    <RequiredPlugin pluginName="Sofa.Component.IO.Mesh"/> <!-- Needed to use components [MeshGmshLoader MeshOBJLoader] -->
    <RequiredPlugin pluginName="Sofa.Component.LinearSolver.Iterative"/> <!-- Needed to use components [CGLinearSolver] -->
    <RequiredPlugin pluginName="Sofa.Component.Mapping.Linear"/> <!-- Needed to use components [BarycentricMapping] -->
    <RequiredPlugin pluginName="Sofa.Component.Mass"/> <!-- Needed to use components [UniformMass] -->
    <RequiredPlugin pluginName="Sofa.Component.IntegrationScheme.Backward"/> <!-- Needed to use components [EulerImplicitIntegrationScheme] -->
    <RequiredPlugin pluginName="Sofa.Component.SolidMechanics.FEM.Elastic"/> <!-- Needed to use components [TetrahedronFEMForceField] -->
    <RequiredPlugin pluginName="Sofa.Component.SolidMechanics.Spring"/> <!-- Needed to use components [MeshSpringForceField] -->
    <RequiredPlugin pluginName="Sofa.Component.StateContainer"/> <!-- Needed to use components [MechanicalObject] -->
    <RequiredPlugin pluginName="Sofa.Component.Topology.Container.Constant"/> <!-- Needed to use components [MeshTopology] -->
    <RequiredPlugin pluginName="Sofa.GL.Component.Rendering3D"/> <!-- Needed to use components [OglModel] -->
    <DefaultAnimationLoop/>

    <Node name="Reference">
        <MeshOBJLoader name="meshLoader_3" filename="mesh/truthcylinder1-bent.obj" scale="0.95" handleSeams="1" />
        <OglModel src="@meshLoader_3" dx="0" dy="-1" dz="0" color="green" />
    </Node>
    <Node name="Springs">
        <EulerImplicitIntegrationScheme name="cg_odesolver"  rayleighStiffness="0.1" rayleighMass="0.1" />
        <CGLinearSolver iterations="100" tolerance="1e-5" threshold="1e-5"/>
        <MeshGmshLoader name="loader" filename="mesh/truthcylinder1.msh" />
        <MeshTopology src="@loader" />
        <MechanicalObject src="@loader" dx="15" />
        <UniformMass totalMass="15" />
        <FixedProjectiveConstraint indices="0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 268 269 270 271 343 345" />
        <MeshSpringForceField name="Spring" tetrasStiffness="1870" tetrasDamping="0" />
        <Node>
            <MeshOBJLoader name="meshLoader_0" filename="mesh/truthcylinder1.obj" handleSeams="1" />
            <OglModel name="Visual" src="@meshLoader_0" color="yellow" dx="15" />
            <BarycentricMapping input="@.." output="@Visual" />
        </Node>
    </Node>
    <Node name="CoFEM">
        <EulerImplicitIntegrationScheme name="cg_odesolver" />
        <CGLinearSolver iterations="100" tolerance="1e-5" threshold="1e-5"/>
        <MeshGmshLoader name="loader" filename="mesh/truthcylinder1.msh" />
        <MeshTopology src="@loader" />
        <MechanicalObject src="@loader" dx="30" />
        <UniformMass totalMass="15" />
        <FixedProjectiveConstraint indices="0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 268 269 270 271 343 345" />
        <TetrahedronFEMForceField name="FEM" youngModulus="1116" poissonRatio="0.49" method="polar" />
        <Node>
            <MeshOBJLoader name="meshLoader_4" filename="mesh/truthcylinder1.obj" handleSeams="1" />
            <OglModel name="Visual" src="@meshLoader_4" color="cyan" dx="30" />
            <BarycentricMapping input="@.." output="@Visual" />
        </Node>
    </Node>
    <Node name="CoFEM_firstOrder">
        <EulerImplicitIntegrationScheme name="cg_odesolver" firstOrder="1" />
        <CGLinearSolver iterations="100" tolerance="1e-5" threshold="1e-5"/>
        <MeshGmshLoader name="loader" filename="mesh/truthcylinder1.msh" />
        <MeshTopology src="@loader" />
        <MechanicalObject src="@loader" dx="45" />
        <UniformMass totalMass="15" />
        <FixedProjectiveConstraint indices="0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 268 269 270 271 343 345" />
        <TetrahedronFEMForceField name="FEM" youngModulus="1116" poissonRatio="0.49" method="polar" />
        <Node>
            <MeshOBJLoader name="meshLoader_1" filename="mesh/truthcylinder1.obj" handleSeams="1" />
            <OglModel name="Visual" src="@meshLoader_1" color="blue" dx="45" />
            <BarycentricMapping input="@.." output="@Visual" />
        </Node>
    </Node>
    <Node name="LinearFEM">
        <EulerImplicitIntegrationScheme name="cg_odesolver" />
        <CGLinearSolver iterations="100" tolerance="1e-5" threshold="1e-5"/>
        <MeshGmshLoader name="loader" filename="mesh/truthcylinder1.msh" />
        <MeshTopology src="@loader" />
        <MechanicalObject src="@loader" dx="60" />
        <UniformMass totalMass="15" />
        <FixedProjectiveConstraint indices="0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 268 269 270 271 343 345" />
        <TetrahedronFEMForceField name="FEM" youngModulus="1116" poissonRatio="0.49" method="small" />
        <Node>
            <MeshOBJLoader name="meshLoader_2" filename="mesh/truthcylinder1.obj" handleSeams="1" />
            <OglModel name="Visual" src="@meshLoader_2" color="red" dx="60" />
            <BarycentricMapping input="@.." output="@Visual" />
        </Node>
    </Node>
</Node>
def createScene(root_node):

   root = root_node.addChild('root', gravity="-1.8 0 100", dt="0.1")

   root.addObject('RequiredPlugin', pluginName="Sofa.Component.Constraint.Projective")
   root.addObject('RequiredPlugin', pluginName="Sofa.Component.IO.Mesh")
   root.addObject('RequiredPlugin', pluginName="Sofa.Component.LinearSolver.Iterative")
   root.addObject('RequiredPlugin', pluginName="Sofa.Component.Mapping.Linear")
   root.addObject('RequiredPlugin', pluginName="Sofa.Component.Mass")
   root.addObject('RequiredPlugin', pluginName="Sofa.Component.IntegrationScheme.Backward")
   root.addObject('RequiredPlugin', pluginName="Sofa.Component.SolidMechanics.FEM.Elastic")
   root.addObject('RequiredPlugin', pluginName="Sofa.Component.SolidMechanics.Spring")
   root.addObject('RequiredPlugin', pluginName="Sofa.Component.StateContainer")
   root.addObject('RequiredPlugin', pluginName="Sofa.Component.Topology.Container.Constant")
   root.addObject('RequiredPlugin', pluginName="Sofa.GL.Component.Rendering3D")
   root.addObject('DefaultAnimationLoop', )

   reference = root.addChild('Reference')

   reference.addObject('MeshOBJLoader', name="meshLoader_3", filename="mesh/truthcylinder1-bent.obj", scale="0.95", handleSeams="1")
   reference.addObject('OglModel', src="@meshLoader_3", dx="0", dy="-1", dz="0", color="green")

   springs = root.addChild('Springs')

   springs.addObject('EulerImplicitIntegrationScheme', name="cg_odesolver", rayleighStiffness="0.1", rayleighMass="0.1")
   springs.addObject('CGLinearSolver', iterations="100", tolerance="1e-5", threshold="1e-5")
   springs.addObject('MeshGmshLoader', name="loader", filename="mesh/truthcylinder1.msh")
   springs.addObject('MeshTopology', src="@loader")
   springs.addObject('MechanicalObject', src="@loader", dx="15")
   springs.addObject('UniformMass', totalMass="15")
   springs.addObject('FixedProjectiveConstraint', indices="0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 268 269 270 271 343 345")
   springs.addObject('MeshSpringForceField', name="Spring", tetrasStiffness="1870", tetrasDamping="0")

   node = Springs.addChild('node')

   node.addObject('MeshOBJLoader', name="meshLoader_0", filename="mesh/truthcylinder1.obj", handleSeams="1")
   node.addObject('OglModel', name="Visual", src="@meshLoader_0", color="yellow", dx="15")
   node.addObject('BarycentricMapping', input="@..", output="@Visual")

   co_fem = root.addChild('CoFEM')

   co_fem.addObject('EulerImplicitIntegrationScheme', name="cg_odesolver")
   co_fem.addObject('CGLinearSolver', iterations="100", tolerance="1e-5", threshold="1e-5")
   co_fem.addObject('MeshGmshLoader', name="loader", filename="mesh/truthcylinder1.msh")
   co_fem.addObject('MeshTopology', src="@loader")
   co_fem.addObject('MechanicalObject', src="@loader", dx="30")
   co_fem.addObject('UniformMass', totalMass="15")
   co_fem.addObject('FixedProjectiveConstraint', indices="0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 268 269 270 271 343 345")
   co_fem.addObject('TetrahedronFEMForceField', name="FEM", youngModulus="1116", poissonRatio="0.49", method="polar")

   node = CoFEM.addChild('node')

   node.addObject('MeshOBJLoader', name="meshLoader_4", filename="mesh/truthcylinder1.obj", handleSeams="1")
   node.addObject('OglModel', name="Visual", src="@meshLoader_4", color="cyan", dx="30")
   node.addObject('BarycentricMapping', input="@..", output="@Visual")

   co_fem_first_order = root.addChild('CoFEM_firstOrder')

   co_fem_first_order.addObject('EulerImplicitIntegrationScheme', name="cg_odesolver", firstOrder="1")
   co_fem_first_order.addObject('CGLinearSolver', iterations="100", tolerance="1e-5", threshold="1e-5")
   co_fem_first_order.addObject('MeshGmshLoader', name="loader", filename="mesh/truthcylinder1.msh")
   co_fem_first_order.addObject('MeshTopology', src="@loader")
   co_fem_first_order.addObject('MechanicalObject', src="@loader", dx="45")
   co_fem_first_order.addObject('UniformMass', totalMass="15")
   co_fem_first_order.addObject('FixedProjectiveConstraint', indices="0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 268 269 270 271 343 345")
   co_fem_first_order.addObject('TetrahedronFEMForceField', name="FEM", youngModulus="1116", poissonRatio="0.49", method="polar")

   node = CoFEM_firstOrder.addChild('node')

   node.addObject('MeshOBJLoader', name="meshLoader_1", filename="mesh/truthcylinder1.obj", handleSeams="1")
   node.addObject('OglModel', name="Visual", src="@meshLoader_1", color="blue", dx="45")
   node.addObject('BarycentricMapping', input="@..", output="@Visual")

   linear_fem = root.addChild('LinearFEM')

   linear_fem.addObject('EulerImplicitIntegrationScheme', name="cg_odesolver")
   linear_fem.addObject('CGLinearSolver', iterations="100", tolerance="1e-5", threshold="1e-5")
   linear_fem.addObject('MeshGmshLoader', name="loader", filename="mesh/truthcylinder1.msh")
   linear_fem.addObject('MeshTopology', src="@loader")
   linear_fem.addObject('MechanicalObject', src="@loader", dx="60")
   linear_fem.addObject('UniformMass', totalMass="15")
   linear_fem.addObject('FixedProjectiveConstraint', indices="0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 268 269 270 271 343 345")
   linear_fem.addObject('TetrahedronFEMForceField', name="FEM", youngModulus="1116", poissonRatio="0.49", method="small")

   node = LinearFEM.addChild('node')

   node.addObject('MeshOBJLoader', name="meshLoader_2", filename="mesh/truthcylinder1.obj", handleSeams="1")
   node.addObject('OglModel', name="Visual", src="@meshLoader_2", color="red", dx="60")
   node.addObject('BarycentricMapping', input="@..", output="@Visual")

EulerImplicitIntegrationScheme.scn

<Node name="root" gravity="-1.8 0 100" dt="0.0001">
    <RequiredPlugin pluginName="Sofa.Component.Constraint.Projective"/> <!-- Needed to use components [FixedProjectiveConstraint] -->
    <RequiredPlugin pluginName="Sofa.Component.IO.Mesh"/> <!-- Needed to use components [MeshGmshLoader MeshOBJLoader] -->
    <RequiredPlugin pluginName="Sofa.Component.LinearSolver.Iterative"/> <!-- Needed to use components [CGLinearSolver] -->
    <RequiredPlugin pluginName="Sofa.Component.Mapping.Linear"/> <!-- Needed to use components [BarycentricMapping] -->
    <RequiredPlugin pluginName="Sofa.Component.Mass"/> <!-- Needed to use components [MeshMatrixMass] -->
    <RequiredPlugin pluginName="Sofa.Component.IntegrationScheme.Backward"/> <!-- Needed to use components [EulerImplicitIntegrationScheme] -->
    <RequiredPlugin pluginName="Sofa.Component.SolidMechanics.FEM.Elastic"/> <!-- Needed to use components [TetrahedronFEMForceField] -->
    <RequiredPlugin pluginName="Sofa.Component.StateContainer"/> <!-- Needed to use components [MechanicalObject] -->
    <RequiredPlugin pluginName="Sofa.Component.Topology.Container.Dynamic"/> <!-- Needed to use components [TetrahedronSetGeometryAlgorithms TetrahedronSetTopologyContainer] -->
    <RequiredPlugin pluginName="Sofa.GL.Component.Rendering3D"/> <!-- Needed to use components [OglModel] -->
    <DefaultAnimationLoop/>

    <Node name="DeformableObject">

        <EulerImplicitIntegrationScheme name="odeImplicitSolver" computeResidual="true"/>
        <CGLinearSolver iterations="1000" tolerance="1e-9" threshold="1e-9"/>

        <MeshGmshLoader name="loader" filename="mesh/truthcylinder1.msh" />
        <TetrahedronSetTopologyContainer src="@loader" name="topologyContainer"/>
        <TetrahedronSetGeometryAlgorithms name="geomAlgo"/>
        <MechanicalObject src="@loader" dx="60" />
        <MeshMatrixMass totalMass="15" topology="@topologyContainer"/>
        <FixedProjectiveConstraint indices="0 1 2 3 4 5 6 7 8 9 10 &#x0A;&#x09;&#x09;&#x09;&#x09;&#x09;&#x09;&#x09;11 12 13 14 15 16 17 18 19 20 &#x0A;&#x09;&#x09;&#x09;&#x09;&#x09;&#x09;&#x09;21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 &#x0A;&#x09;&#x09;&#x09;&#x09;&#x09;&#x09;&#x09;41 42 43 44 45 46 47 268 269 270 271 343 345" />
        <TetrahedronFEMForceField name="FEM" youngModulus="1000" poissonRatio="0.49" method="small" />

        <Node>
            <MeshOBJLoader name="meshLoader_0" filename="mesh/truthcylinder1.obj" handleSeams="1" />
            <OglModel name="Visual" src="@meshLoader_0" color="red" dx="60" />
            <BarycentricMapping input="@.." output="@Visual" />
        </Node>
    </Node>
</Node>
def createScene(root_node):

   root = root_node.addChild('root', gravity="-1.8 0 100", dt="0.0001")

   root.addObject('RequiredPlugin', pluginName="Sofa.Component.Constraint.Projective")
   root.addObject('RequiredPlugin', pluginName="Sofa.Component.IO.Mesh")
   root.addObject('RequiredPlugin', pluginName="Sofa.Component.LinearSolver.Iterative")
   root.addObject('RequiredPlugin', pluginName="Sofa.Component.Mapping.Linear")
   root.addObject('RequiredPlugin', pluginName="Sofa.Component.Mass")
   root.addObject('RequiredPlugin', pluginName="Sofa.Component.IntegrationScheme.Backward")
   root.addObject('RequiredPlugin', pluginName="Sofa.Component.SolidMechanics.FEM.Elastic")
   root.addObject('RequiredPlugin', pluginName="Sofa.Component.StateContainer")
   root.addObject('RequiredPlugin', pluginName="Sofa.Component.Topology.Container.Dynamic")
   root.addObject('RequiredPlugin', pluginName="Sofa.GL.Component.Rendering3D")
   root.addObject('DefaultAnimationLoop', )

   deformable_object = root.addChild('DeformableObject')

   deformable_object.addObject('EulerImplicitIntegrationScheme', name="odeImplicitSolver", computeResidual="true")
   deformable_object.addObject('CGLinearSolver', iterations="1000", tolerance="1e-9", threshold="1e-9")
   deformable_object.addObject('MeshGmshLoader', name="loader", filename="mesh/truthcylinder1.msh")
   deformable_object.addObject('TetrahedronSetTopologyContainer', src="@loader", name="topologyContainer")
   deformable_object.addObject('TetrahedronSetGeometryAlgorithms', name="geomAlgo")
   deformable_object.addObject('MechanicalObject', src="@loader", dx="60")
   deformable_object.addObject('MeshMatrixMass', totalMass="15", topology="@topologyContainer")
   deformable_object.addObject('FixedProjectiveConstraint', indices="0 1 2 3 4 5 6 7 8 9 10 
                        11 12 13 14 15 16 17 18 19 20 
                        21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 
                        41 42 43 44 45 46 47 268 269 270 271 343 345")
   deformable_object.addObject('TetrahedronFEMForceField', name="FEM", youngModulus="1000", poissonRatio="0.49", method="small")

   node = DeformableObject.addChild('node')

   node.addObject('MeshOBJLoader', name="meshLoader_0", filename="mesh/truthcylinder1.obj", handleSeams="1")
   node.addObject('OglModel', name="Visual", src="@meshLoader_0", color="red", dx="60")
   node.addObject('BarycentricMapping', input="@..", output="@Visual")