Description

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

The direction D represents a derivative vector to be used in ANCF elements.

#include <ChNodeFEAxyzD.h>

Inheritance diagram for chrono::fea::ChNodeFEAxyzD:

[legend]

Collaboration diagram for chrono::fea::ChNodeFEAxyzD:

[legend]

Public Member Functions
	ChNodeFEAxyzD (ChVector3d initial_pos=VNULL, ChVector3d initial_dir=VECT_X)

	ChNodeFEAxyzD (const ChNodeFEAxyzD &other)

ChNodeFEAxyzD &	operator= (const ChNodeFEAxyzD &other)

void	SetSlope1 (const ChVector3d &d)
	Set the derivative vector.

const ChVector3d &	GetSlope1 () const
	Get the derivative vector.

void	SetSlope1Dt (const ChVector3d &dt)
	Set the speed of the derivative vector.

const ChVector3d &	GetSlope1Dt () const
	Get the speed of the derivative vector.

void	SetSlope1Dt2 (const ChVector3d &dtt)
	Set the acceleration of the derivative vector.

const ChVector3d &	GetSlope1Dt2 () const
	Get the acceleration of the derivative vector.

ChVariables &	VariablesSlope1 ()

virtual void	ForceToRest () override
	Reset to no speed and acceleration.

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	SetSlope1Fixed (bool fixed)
	Fix/release the derivative vector states. More...

bool	IsSlope1Fixed () const
	Return true if the derivative vector states are fixed.

virtual unsigned int	GetNumCoordsPosLevel () const override
	Get the number of degrees of freedom.

virtual unsigned int	GetNumCoordsVelLevel () const override
	Get the number of degrees of freedom, derivative.

virtual unsigned int	GetNumCoordsPosLevelActive () const override
	Get the actual number of active degrees of freedom.

virtual unsigned int	GetNumCoordsVelLevelActive () const override
	Get the actual number of active degrees of freedom, derivative.

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.

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

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	NodeIntLoadLumpedMass_Md (const unsigned int off, ChVectorDynamic<> &Md, double &error, 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
	Register with the given system descriptor any ChVariable objects associated with this item.

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 unsigned int	GetLoadableNumCoordsPosLevel () override
	Gets the number of DOFs affected by this element (position part).

virtual unsigned int	GetLoadableNumCoordsVelLevel () override
	Gets the number of DOFs affected by this element (speed part).

virtual void	LoadableGetStateBlockPosLevel (int block_offset, ChState &S) override
	Gets all the DOFs packed in a single vector (position part).

virtual void	LoadableGetStateBlockVelLevel (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 unsigned int	GetNumFieldCoords () override
	Number of coordinates in the interpolated field.

virtual unsigned int	GetSubBlockSize (unsigned 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...

Public Member Functions inherited from chrono::fea::ChNodeFEAxyz
	ChNodeFEAxyz (ChVector3d initial_pos=VNULL)

	ChNodeFEAxyz (const ChNodeFEAxyz &other)

ChNodeFEAxyz &	operator= (const ChNodeFEAxyz &other)

virtual ChVariablesNode &	Variables () 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 (const ChVector3d &x)
	Set the initial (reference) position.

virtual const ChVector3d &	GetX0 () const
	Get the initial (reference) position.

virtual void	SetForce (const ChVector3d &frc)
	Set the 3d applied force, in absolute reference.

virtual const ChVector3d &	GetForce () const
	Get the 3d applied force, in absolute reference.

virtual ChVariables *	GetVariables1 () 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)

ChNodeBase &	operator= (const ChNodeBase &other)

virtual bool	IsAllCoordsActive () const
	Return true if all node DOFs are active (no node variable is fixed).

unsigned int	NodeGetOffsetPosLevel ()
	Get offset in the state vector (position part).

unsigned int	NodeGetOffsetVelLevel ()
	Get offset in the state vector (speed part).

void	NodeSetOffsetPosLevel (const unsigned int moff)
	Set offset in the state vector (position part).

void	NodeSetOffsetVelLevel (const unsigned int moff)
	Set offset in the state vector (speed part).

Public Member Functions inherited from chrono::ChNodeXYZ
	ChNodeXYZ (const ChVector3d &initial_pos)

	ChNodeXYZ (const ChNodeXYZ &other)

ChNodeXYZ &	operator= (const ChNodeXYZ &other)

const ChVector3d &	GetPos () const

void	SetPos (const ChVector3d &mpos)

const ChVector3d &	GetPosDt () const

void	SetPosDt (const ChVector3d &mposdt)

const ChVector3d &	GetPosDt2 () const

void	SetPosDt2 (const ChVector3d &mposdtdt)

virtual unsigned int	GetNumSubBlocks () override
	Get the number of DOFs sub-blocks.

virtual unsigned int	GetSubBlockOffset (unsigned int nblock) override
	Get the offset of the specified sub-block of DOFs in global vector.

virtual bool	IsSubBlockActive (unsigned 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.

Public Attributes
unsigned int	m_dof_actual
	actual number of degrees of freedom

Public Attributes inherited from chrono::fea::ChNodeFEAbase
double	m_TotalMass
	Nodal mass obtained from element mass matrix.

Public Attributes inherited from chrono::ChNodeXYZ
ChVector3d	pos

ChVector3d	pos_dt

ChVector3d	pos_dtdt

Protected Member Functions
ChVectorDynamic &	GetMassDiagonalSlope1 ()
	Get mass of the node (corresponding to the slope derivative).

Protected Attributes
ChVariablesGenericDiagonalMass *	variables_D
	derivative vector

ChVector3d	D

ChVector3d	D_dt

ChVector3d	D_dtdt

Protected Attributes inherited from chrono::fea::ChNodeFEAxyz
ChVariablesNode	variables
	3D node variables, with x,y,z

ChVector3d	X0
	reference position

ChVector3d	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)

Additional Inherited Members
Public Types inherited from chrono::ChVariableTupleCarrier_1vars< 3 >
typedef ChConstraintTuple_1vars< ChVariableTupleCarrier_1vars< N1 > >	type_constraint_tuple

Static Public Attributes inherited from chrono::ChVariableTupleCarrier_1vars< 3 >
static const int	nvars1

Member Function Documentation

◆ ComputeNF()

void chrono::fea::ChNodeFEAxyzD::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

U	x coordinate of application point in absolute space
V	y coordinate of application point in absolute space
W	z coordinate of application point in absolute space
Qi	Return result of N'*F here, maybe with offset block_offset
detJ	Return det[J] here
F	Input F vector, containing Force xyz in absolute coords and a 'pseudo' torque.
state_x	if != 0, update state (pos. part) to this, then evaluate Q
state_w	if != 0, update state (speed part) to this, then evaluate Q

Reimplemented from chrono::ChNodeXYZ.

Reimplemented in chrono::fea::ChNodeFEAxyzDDD, and chrono::fea::ChNodeFEAxyzDD.

◆ SetFixed()

void chrono::fea::ChNodeFEAxyzD::SetFixed ( bool fixed )

overridevirtual

Fix/release this node.

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

Reimplemented from chrono::fea::ChNodeFEAxyz.

Reimplemented in chrono::fea::ChNodeFEAxyzDDD, and chrono::fea::ChNodeFEAxyzDD.

◆ SetSlope1Fixed()

void chrono::fea::ChNodeFEAxyzD::SetSlope1Fixed ( bool fixed )

Fix/release the derivative vector states.

If fixed, these states are not changed by the solver.

◆ VariablesFbIncrementMq()

void chrono::fea::ChNodeFEAxyzD::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::ChNodeFEAxyz.

Reimplemented in chrono::fea::ChNodeFEAxyzDDD, and chrono::fea::ChNodeFEAxyzDD.

◆ VariablesFbLoadForces()

void chrono::fea::ChNodeFEAxyzD::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::ChNodeFEAxyz.

Reimplemented in chrono::fea::ChNodeFEAxyzDDD, and chrono::fea::ChNodeFEAxyzDD.

◆ VariablesQbIncrementPosition()

void chrono::fea::ChNodeFEAxyzD::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 (Euler integration).

Reimplemented from chrono::fea::ChNodeFEAxyz.

Reimplemented in chrono::fea::ChNodeFEAxyzDDD, and chrono::fea::ChNodeFEAxyzDD.

◆ VariablesQbSetSpeed()

void chrono::fea::ChNodeFEAxyzD::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::ChNodeFEAxyz.

Reimplemented in chrono::fea::ChNodeFEAxyzDDD, and chrono::fea::ChNodeFEAxyzDD.

The documentation for this class was generated from the following files:

/builds/uwsbel/chrono/src/chrono/fea/ChNodeFEAxyzD.h
/builds/uwsbel/chrono/src/chrono/fea/ChNodeFEAxyzD.cpp

Description

Public Member Functions

Public Attributes

Protected Member Functions

Protected Attributes

Additional Inherited Members

Member Function Documentation

◆ ComputeNF()

◆ SetFixed()

◆ SetSlope1Fixed()

◆ VariablesFbIncrementMq()

◆ VariablesFbLoadForces()

◆ VariablesQbIncrementPosition()

◆ VariablesQbSetSpeed()