Description

Base class for loads representing a concentrated force acting on a ChNodeXYZ.

Users should inherit from this and implement custom ComputeForce(). Note: there are already some predefined examples, ie. children classes with common concrete implementations, such as ChLoadXYZnodeForceAbsolute ; take inspiration from those example to inherit your own load if they are not enough.

#include <ChLoadsXYZnode.h>

Inheritance diagram for chrono::ChLoadXYZnodeForce:

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Collaboration diagram for chrono::ChLoadXYZnodeForce:

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Public Member Functions
	ChLoadXYZnodeForce (std::shared_ptr< ChNodeXYZ > node)

virtual void	ComputeForce (const ChVector3d &abs_pos, const ChVector3d &abs_vel, ChVector3d &abs_force)=0
	Compute the force on the node, in absolute coordsystem, given position of node as abs_pos. More...

virtual void	ComputeQ (ChState state_x, ChStateDelta state_w) override
	Compute Q, the generalized load. More...

ChVector3d	GetForce () const
	For diagnosis purposes, this can return the actual last computed value of the applied force, expressed in absolute coordinate system, assumed applied to node.

Public Member Functions inherited from chrono::ChLoadCustom
	ChLoadCustom (std::shared_ptr< ChLoadable > loadable_object)

virtual int	LoadGetNumCoordsPosLevel () override
	Gets the number of DOFs affected by this load (position part).

virtual int	LoadGetNumCoordsVelLevel () override
	Gets the number of DOFs affected by this load (speed part).

virtual void	LoadGetStateBlock_x (ChState &mD) override
	Gets all the current DOFs packed in a single vector (position part).

virtual void	LoadGetStateBlock_w (ChStateDelta &mD) override
	Gets all the current DOFs packed in a single vector (speed part).

virtual void	LoadStateIncrement (const ChState &x, const ChStateDelta &dw, ChState &x_new) override
	Increment a packed state (e.g., as obtained by LoadGetStateBlock_x()) by a given packed state-delta. More...

virtual int	LoadGetNumFieldCoords () override
	Number of coordinates in the interpolated field. More...

virtual void	ComputeJacobian (ChState state_x, ChStateDelta state_w) override
	Compute Jacobian matrices K=-dQ/dx, R=-dQ/dv, and M=-dQ/da. More...

virtual void	LoadIntLoadResidual_F (ChVectorDynamic<> &R, double c) override
	Add the internal loads Q (pasted at global offsets) into a global vector R, multiplied by a scaling factor c. More...

virtual void	LoadIntLoadResidual_Mv (ChVectorDynamic<> &R, const ChVectorDynamic<> &w, double c) override
	Increment a vector R with the matrix-vector product M*w, scaled by the factor c. More...

virtual void	LoadIntLoadLumpedMass_Md (ChVectorDynamic<> &Md, double &err, const double c) override
	Add the lumped mass to an Md vector, representing a mass diagonal matrix. More...

virtual void	CreateJacobianMatrices () override
	Create the Jacobian loads if needed and set the ChVariables referenced by the sparse KRM block.

virtual ChVectorDynamic &	GetQ ()
	Access the generalized load vector Q.

Public Member Functions inherited from chrono::ChLoadBase
ChLoadJacobians *	GetJacobians ()
	Access the Jacobians (if any, i.e. if this is a stiff load).

virtual void	InjectKRMMatrices (ChSystemDescriptor &descriptor)
	Register with the given system descriptor any ChKRMBlock objects associated with this item.

virtual void	LoadKRMMatrices (double Kfactor, double Rfactor, double Mfactor)
	Compute and load current stiffnes (K), damping (R), and mass (M) matrices in encapsulated ChKRMBlock objects. More...

Public Member Functions inherited from chrono::ChObj
	ChObj (const ChObj &other)

virtual ChObj *	Clone () const =0
	"Virtual" copy constructor.

int	GetIdentifier () const
	Get the unique integer identifier of this object. More...

void	SetTag (int tag)
	Set an object integer tag (default: -1). More...

int	GetTag () const
	Get the tag of this object.

void	SetName (const std::string &myname)
	Set the name of this object.

std::string	GetName () const
	Get the name of this object.

double	GetChTime () const
	Gets the simulation time of this object.

void	SetChTime (double m_time)
	Sets the simulation time of this object.

virtual void	ArchiveOut (ChArchiveOut &archive_out)
	Method to allow serialization of transient data to archives.

virtual void	ArchiveIn (ChArchiveIn &archive_in)
	Method to allow de-serialization of transient data from archives.

virtual std::string &	ArchiveContainerName ()

Protected Member Functions
virtual bool	IsStiff () override
	Inherited classes could override this and return true, if the load benefits from a jacobian when using implicit integrators.

virtual void	Update (double time) override
	Update, called at least at each time step. More...

Protected Member Functions inherited from chrono::ChObj
int	GenerateUniqueIdentifier ()

Protected Attributes
ChVector3d	computed_abs_force

Protected Attributes inherited from chrono::ChLoadBase
ChLoadJacobians *	m_jacobians

Protected Attributes inherited from chrono::ChObj
double	ChTime
	object simulation time

std::string	m_name
	object name

int	m_identifier
	object unique identifier

int	m_tag
	user-supplied tag

Additional Inherited Members
Public Attributes inherited from chrono::ChLoadCustom
std::shared_ptr< ChLoadable >	loadable

ChVectorDynamic	load_Q

Member Function Documentation

◆ ComputeForce()

virtual void chrono::ChLoadXYZnodeForce::ComputeForce	(	const ChVector3d &	abs_pos,
		const ChVector3d &	abs_vel,
		ChVector3d &	abs_force
	)

pure virtual

Compute the force on the node, in absolute coordsystem, given position of node as abs_pos.

Inherited classes MUST IMPLEMENT THIS.

Implemented in chrono::ChLoadXYZnodeForceAbsolute.

◆ ComputeQ()

void chrono::ChLoadXYZnodeForce::ComputeQ	(	ChState *	state_x,
		ChStateDelta *	state_w
	)

overridevirtual

Compute Q, the generalized load.

Called automatically at each Update().

Parameters

state_x	state position to evaluate Q
state_w	state speed to evaluate Q

Implements chrono::ChLoadBase.

◆ Update()

void chrono::ChLoadXYZnodeForce::Update ( double time )

overrideprotectedvirtual

Update, called at least at each time step.

It recomputes the generalized load Q vector(s)
It recomputes the Jacobian matrices K,R,M in case of stiff load Q and Jacobians assumed evaluated at the current state. Jacobians are automatically allocated if needed.

Reimplemented from chrono::ChLoadBase.

Reimplemented in chrono::ChLoadXYZnodeForceAbsolute.

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

/builds/uwsbel/chrono/src/chrono/physics/ChLoadsXYZnode.h
/builds/uwsbel/chrono/src/chrono/physics/ChLoadsXYZnode.cpp

Description

Public Member Functions

Protected Member Functions

Protected Attributes

Additional Inherited Members

Member Function Documentation

◆ ComputeForce()

◆ ComputeQ()

◆ Update()