Description

Class for a generic 3D finite element node, with x,y,z displacement, and 3 position vector derivatives.

For a Fully Parameterized ANCF element:

  • The variable D represents the position vector gradient with respect to the 1st element coordinate line.
  • The variable DD represents the position vector gradient with respect to the 2nd element coordinate line.
  • The variable DDD represents the position vector gradient with respect to the 3rd element coordinate line. Other ANCF elements may use these derivative vectors differently.

#include <ChNodeFEAxyzDDD.h>

Inheritance diagram for chrono::fea::ChNodeFEAxyzDDD:
Collaboration diagram for chrono::fea::ChNodeFEAxyzDDD:

Public Member Functions

 ChNodeFEAxyzDDD (ChVector<> initial_pos=VNULL, ChVector<> initial_dir_u=VECT_X, ChVector<> initial_dir_v=VECT_Y, ChVector<> initial_dir_w=VECT_Z)
 
 ChNodeFEAxyzDDD (const ChNodeFEAxyzDDD &other)
 
ChNodeFEAxyzDDDoperator= (const ChNodeFEAxyzDDD &other)
 
void SetDDD (const ChVector<> &d)
 Set the 3rd derivative vector.
 
const ChVectorGetDDD () const
 Get the 3rd derivative vector.
 
void SetDDD_dt (const ChVector<> &dt)
 Set the speed of the 3rd derivative vector.
 
const ChVectorGetDDD_dt () const
 Get the speed of the 3rd derivative vector.
 
void SetDDD_dtdt (const ChVector<> &dtt)
 Set the acceleration of the 3rd derivative vector.
 
const ChVectorGetDDD_dtdt () const
 Get the acceleration of the 3rd derivative vector.
 
ChVariablesVariables_DDD ()
 
virtual void SetNoSpeedNoAcceleration () override
 Reset to no speed and acceleration.
 
ChVectorDynamicGetMassDiagonalDDD ()
 Get mass of the node (for DDD variables).
 
virtual void SetFixed (bool fixed) override
 Fix/release this node. More...
 
virtual bool IsFixed () const override
 Return true if the node is fixed (i.e., its state variables are not changed by the solver).
 
void SetFixedDDD (bool fixed)
 Fix/release the 3rd derivative vector states. More...
 
bool IsFixedDDD () const
 Return true if the 3rd derivative vector states are fixed.
 
virtual int GetNdofX () const override
 Get the number of degrees of freedom.
 
virtual int GetNdofX_active () const override
 Get the actual number of active degrees of freedom.
 
virtual void NodeIntStateGather (const unsigned int off_x, ChState &x, const unsigned int off_v, ChStateDelta &v, double &T) override
 
virtual void NodeIntStateScatter (const unsigned int off_x, const ChState &x, const unsigned int off_v, const ChStateDelta &v, const double T) override
 
virtual void NodeIntStateGatherAcceleration (const unsigned int off_a, ChStateDelta &a) override
 
virtual void NodeIntStateScatterAcceleration (const unsigned int off_a, const ChStateDelta &a) override
 
virtual void NodeIntStateIncrement (const unsigned int off_x, ChState &x_new, const ChState &x, const unsigned int off_v, const ChStateDelta &Dv) override
 
virtual void NodeIntStateGetIncrement (const unsigned int off_x, const ChState &x_new, const ChState &x, const unsigned int off_v, ChStateDelta &Dv) override
 
virtual void NodeIntLoadResidual_F (const unsigned int off, ChVectorDynamic<> &R, const double c) override
 
virtual void NodeIntLoadResidual_Mv (const unsigned int off, ChVectorDynamic<> &R, const ChVectorDynamic<> &w, const double c) override
 
virtual void NodeIntToDescriptor (const unsigned int off_v, const ChStateDelta &v, const ChVectorDynamic<> &R) override
 
virtual void NodeIntFromDescriptor (const unsigned int off_v, ChStateDelta &v) override
 
virtual void InjectVariables (ChSystemDescriptor &descriptor) override
 Tell to a system descriptor that there are variables of type ChVariables in this object (for further passing it to a solver).
 
virtual void VariablesFbReset () override
 Set the 'fb' part (the known term) of the encapsulated ChVariables to zero.
 
virtual void VariablesFbLoadForces (double factor=1) override
 Add the current forces (applied to node) into the encapsulated ChVariables. More...
 
virtual void VariablesQbLoadSpeed () override
 Initialize the 'qb' part of the ChVariables with the current value of speeds.
 
virtual void VariablesQbSetSpeed (double step=0) override
 Fetch the item speed (ex. More...
 
virtual void VariablesFbIncrementMq () override
 Add M*q (masses multiplied current 'qb') to Fb, ex. More...
 
virtual void VariablesQbIncrementPosition (double step) override
 Increment node positions by the 'qb' part of the ChVariables, multiplied by a 'step' factor. More...
 
virtual int LoadableGet_ndof_x () override
 Gets the number of DOFs affected by this element (position part).
 
virtual int LoadableGet_ndof_w () override
 Gets the number of DOFs affected by this element (speed part).
 
virtual void LoadableGetStateBlock_x (int block_offset, ChState &S) override
 Gets all the DOFs packed in a single vector (position part).
 
virtual void LoadableGetStateBlock_w (int block_offset, ChStateDelta &S) override
 Gets all the DOFs packed in a single vector (speed part).
 
virtual void LoadableStateIncrement (const unsigned int off_x, ChState &x_new, const ChState &x, const unsigned int off_v, const ChStateDelta &Dv) override
 Increment all DOFs using a delta.
 
virtual int Get_field_ncoords () override
 Number of coordinates in the interpolated field.
 
virtual unsigned int GetSubBlockSize (int nblock) override
 Get the size of the i-th sub-block of DOFs in global vector.
 
virtual void LoadableGetVariables (std::vector< ChVariables * > &vars) override
 Get the pointers to the contained ChVariables, appending to the mvars vector.
 
virtual void ComputeNF (const double U, const double V, const double W, ChVectorDynamic<> &Qi, double &detJ, const ChVectorDynamic<> &F, ChVectorDynamic<> *state_x, ChVectorDynamic<> *state_w) override
 Evaluate Q = N'*F, for Q generalized lagrangian load, where N is some type of matrix evaluated at point P(U,V,W) assumed in absolute coordinates, and F is a load assumed in absolute coordinates. More...
 
virtual void ArchiveOUT (ChArchiveOut &archive) override
 Method to allow serialization of transient data to archives.
 
virtual void ArchiveIN (ChArchiveIn &archive) override
 Method to allow de serialization of transient data from archives.
 
- Public Member Functions inherited from chrono::fea::ChNodeFEAxyzDD
 ChNodeFEAxyzDD (ChVector<> initial_pos=VNULL, ChVector<> initial_dir=VECT_X, ChVector<> initial_curv=VNULL)
 
 ChNodeFEAxyzDD (const ChNodeFEAxyzDD &other)
 
ChNodeFEAxyzDDoperator= (const ChNodeFEAxyzDD &other)
 
void SetDD (const ChVector<> &d)
 Set the 2nd derivative vector.
 
const ChVectorGetDD () const
 Get the 2nd derivative vector.
 
void SetDD_dt (const ChVector<> &dt)
 Set the speed of the 2nd derivative vector.
 
const ChVectorGetDD_dt () const
 Get the speed of the 2nd derivative vector.
 
void SetDD_dtdt (const ChVector<> &dtt)
 Set the acceleration of the 2nd derivative vector.
 
const ChVectorGetDD_dtdt () const
 Get the acceleration of the 2nd derivative vector.
 
ChVariablesVariables_DD ()
 
ChVectorDynamicGetMassDiagonalDD ()
 Get mass of the node (for DD variables).
 
void SetFixedDD (bool fixed)
 Fix/release the 2nd derivative vector states. More...
 
bool IsFixedDD () const
 Return true if the 2nd derivative vector states are fixed.
 
- Public Member Functions inherited from chrono::fea::ChNodeFEAxyzD
 ChNodeFEAxyzD (ChVector<> initial_pos=VNULL, ChVector<> initial_dir=VECT_X)
 
 ChNodeFEAxyzD (const ChNodeFEAxyzD &other)
 
ChNodeFEAxyzDoperator= (const ChNodeFEAxyzD &other)
 
void SetD (const ChVector<> &d)
 Set the derivative vector.
 
const ChVectorGetD () const
 Get the derivative vector.
 
void SetD_dt (const ChVector<> &dt)
 Set the speed of the derivative vector.
 
const ChVectorGetD_dt () const
 Get the speed of the derivative vector.
 
void SetD_dtdt (const ChVector<> &dtt)
 Set the acceleration of the derivative vector.
 
const ChVectorGetD_dtdt () const
 Get the acceleration of the derivative vector.
 
ChVariablesVariables_D ()
 
ChVectorDynamicGetMassDiagonalD ()
 Get mass of the node.
 
void SetFixedD (bool fixed)
 Fix/release the derivative vector states. More...
 
bool IsFixedD () const
 Return true if the derivative vector states are fixed.
 
- Public Member Functions inherited from chrono::fea::ChNodeFEAxyz
 ChNodeFEAxyz (ChVector<> initial_pos=VNULL)
 
 ChNodeFEAxyz (const ChNodeFEAxyz &other)
 
ChNodeFEAxyzoperator= (const ChNodeFEAxyz &other)
 
virtual ChVariablesNodeVariables () override
 
virtual void Relax () override
 Set the rest position as the actual position.
 
virtual double GetMass () const override
 Get mass of the node.
 
virtual void SetMass (double m) override
 Set mass of the node.
 
virtual void SetX0 (ChVector<> x)
 Set the initial (reference) position.
 
virtual ChVector GetX0 ()
 Get the initial (reference) position.
 
virtual void SetForce (ChVector<> f)
 Set the 3d applied force, in absolute reference.
 
virtual ChVector GetForce ()
 Get the 3d applied force, in absolute reference.
 
virtual ChVariablesGetVariables1 () override
 
- Public Member Functions inherited from chrono::fea::ChNodeFEAbase
virtual void SetIndex (unsigned int mindex)
 Sets the global index of the node.
 
virtual unsigned int GetIndex ()
 Gets the global index of the node.
 
- Public Member Functions inherited from chrono::ChNodeBase
 ChNodeBase (const ChNodeBase &other)
 
ChNodeBaseoperator= (const ChNodeBase &other)
 
virtual int GetNdofW () const
 Get the number of degrees of freedom, derivative. More...
 
virtual int GetNdofW_active () const
 Get the actual number of active degrees of freedom, derivative. More...
 
virtual bool UseFullDof () const
 Return true if all node DOFs are active (no node variable is fixed).
 
unsigned int NodeGetOffsetX ()
 Get offset in the state vector (position part).
 
unsigned int NodeGetOffsetW ()
 Get offset in the state vector (speed part).
 
void NodeSetOffset_x (const unsigned int moff)
 Set offset in the state vector (position part).
 
void NodeSetOffset_w (const unsigned int moff)
 Set offset in the state vector (speed part).
 
- Public Member Functions inherited from chrono::ChNodeXYZ
 ChNodeXYZ (const ChVector<> &initial_pos)
 
 ChNodeXYZ (const ChNodeXYZ &other)
 
ChNodeXYZoperator= (const ChNodeXYZ &other)
 
const ChVectorGetPos () const
 
void SetPos (const ChVector<> &mpos)
 
const ChVectorGetPos_dt () const
 
void SetPos_dt (const ChVector<> &mposdt)
 
const ChVectorGetPos_dtdt () const
 
void SetPos_dtdt (const ChVector<> &mposdtdt)
 
virtual int GetSubBlocks () override
 Get the number of DOFs sub-blocks.
 
virtual unsigned int GetSubBlockOffset (int nblock) override
 Get the offset of the specified sub-block of DOFs in global vector.
 
virtual bool IsSubBlockActive (int nblock) const override
 Check if the specified sub-block of DOFs is active.
 
virtual double GetDensity () override
 This is not needed because not used in quadrature.
 
- Public Member Functions inherited from chrono::ChLoadableUVW
virtual bool IsTetrahedronIntegrationNeeded ()
 If true, use quadrature over u,v,w in [0..1] range as tetrahedron volumetric coords (with z=1-u-v-w) otherwise use default quadrature over u,v,w in [-1..+1] as box isoparametric coords.
 
virtual bool IsTrianglePrismIntegrationNeeded ()
 If true, use quadrature over u,v in [0..1] range as triangle natural coords (with z=1-u-v), and use linear quadrature over w in [-1..+1], otherwise use default quadrature over u,v,w in [-1..+1] as box isoparametric coords.
 

Protected Member Functions

virtual void SetupInitial (ChSystem *system) override
 Initial setup. Set number of degrees of freedom for this node.
 

Additional Inherited Members

- Public Types inherited from chrono::ChVariableTupleCarrier_1vars< 3 >
typedef ChConstraintTuple_1vars< ChVariableTupleCarrier_1vars< N1 > > type_constraint_tuple
 
- Public Attributes inherited from chrono::fea::ChNodeFEAbase
double m_TotalMass
 Nodal mass obtained from element masss matrix.
 
- Public Attributes inherited from chrono::ChNodeXYZ
ChVector pos
 
ChVector pos_dt
 
ChVector pos_dtdt
 
- Static Public Attributes inherited from chrono::ChVariableTupleCarrier_1vars< 3 >
static const int nvars1
 
- Protected Attributes inherited from chrono::fea::ChNodeFEAxyzD
int m_dof_actual
 actual number of degrees of freedom
 
- Protected Attributes inherited from chrono::fea::ChNodeFEAxyz
ChVariablesNode variables
 3D node variables, with x,y,z
 
ChVector X0
 reference position
 
ChVector Force
 applied force
 
- Protected Attributes inherited from chrono::fea::ChNodeFEAbase
unsigned int g_index
 global node index
 
- Protected Attributes inherited from chrono::ChNodeBase
unsigned int offset_x
 offset in vector of state (position part)
 
unsigned int offset_w
 offset in vector of state (speed part)
 

Member Function Documentation

◆ ComputeNF()

void chrono::fea::ChNodeFEAxyzDDD::ComputeNF ( const double  U,
const double  V,
const double  W,
ChVectorDynamic<> &  Qi,
double &  detJ,
const ChVectorDynamic<> &  F,
ChVectorDynamic<> *  state_x,
ChVectorDynamic<> *  state_w 
)
overridevirtual

Evaluate Q = N'*F, for Q generalized lagrangian load, where N is some type of matrix evaluated at point P(U,V,W) assumed in absolute coordinates, and F is a load assumed in absolute coordinates.

Here, det[J] is unused.

Parameters
Ux coordinate of application point in absolute space
Vy coordinate of application point in absolute space
Wz coordinate of application point in absolute space
QiReturn result of N'*F here, maybe with offset block_offset
detJReturn det[J] here
FInput F vector, containing Force xyz in absolute coords and a 'pseudo' torque.
state_xif != 0, update state (pos. part) to this, then evaluate Q
state_wif != 0, update state (speed part) to this, then evaluate Q

Reimplemented from chrono::fea::ChNodeFEAxyzDD.

◆ SetFixed()

void chrono::fea::ChNodeFEAxyzDDD::SetFixed ( bool  fixed)
overridevirtual

Fix/release this node.

If fixed, its state variables are not changed by the solver.

Reimplemented from chrono::fea::ChNodeFEAxyzDD.

◆ SetFixedDDD()

void chrono::fea::ChNodeFEAxyzDDD::SetFixedDDD ( bool  fixed)

Fix/release the 3rd derivative vector states.

If fixed, these states are not changed by the solver. Note that releasing the 3rd derivative vector forces the first 2 derivatives vector to also be released.

◆ VariablesFbIncrementMq()

void chrono::fea::ChNodeFEAxyzDDD::VariablesFbIncrementMq ( )
overridevirtual

Add M*q (masses multiplied current 'qb') to Fb, ex.

if qb is initialized with v_old using VariablesQbLoadSpeed, this method can be used in timestepping schemes that do: M*v_new = M*v_old + forces*dt

Reimplemented from chrono::fea::ChNodeFEAxyzDD.

◆ VariablesFbLoadForces()

void chrono::fea::ChNodeFEAxyzDDD::VariablesFbLoadForces ( double  factor = 1)
overridevirtual

Add the current forces (applied to node) into the encapsulated ChVariables.

Include in the 'fb' part: qf+=forces*factor

Reimplemented from chrono::fea::ChNodeFEAxyzDD.

◆ VariablesQbIncrementPosition()

void chrono::fea::ChNodeFEAxyzDDD::VariablesQbIncrementPosition ( double  step)
overridevirtual

Increment node positions by the 'qb' part of the ChVariables, multiplied by a 'step' factor.

pos+=qb*step If qb is a speed, this behaves like a single step of 1-st order numerical integration (Eulero integration).

Reimplemented from chrono::fea::ChNodeFEAxyzDD.

◆ VariablesQbSetSpeed()

void chrono::fea::ChNodeFEAxyzDDD::VariablesQbSetSpeed ( double  step = 0)
overridevirtual

Fetch the item speed (ex.

linear velocity, in xyz nodes) from the 'qb' part of the ChVariables and sets it as the current item speed. If 'step' is not 0, also should compute the approximate acceleration of the item using backward differences, that is accel=(new_speed-old_speed)/step. Mostly used after the solver provided the solution in ChVariables.

Reimplemented from chrono::fea::ChNodeFEAxyzDD.


The documentation for this class was generated from the following files:
  • /builds/uwsbel/chrono/src/chrono/fea/ChNodeFEAxyzDDD.h
  • /builds/uwsbel/chrono/src/chrono/fea/ChNodeFEAxyzDDD.cpp