Translational or rotational friction controller for Hinge, Prismatic and CylindricalJoint. More...

#include <ElementaryConstraint.h>

Inheritance diagram for agx::FrictionController:

Public Member Functions
	FrictionController (const agx::ConstraintAngleBasedData &data)
	Construct given angle based data.

	AGXSTREAM_DECLARE_SERIALIZABLE_BASE (agx::FrictionController)

agx::Bool	getEnableNonLinearDirectSolveUpdate () const

agx::Real	getFrictionCoefficient () const

agx::RangeReal	getMinimumStaticFrictionForceRange () const
	Get the minimum force range that this friction controller can apply.

ConstraintNlmcpCallback *	getNlCallback () const override

virtual agx::Bool	isActive () const override

agx::UInt	iterativePostSolveCallback (const agx::ConstraintImplementation constraint, const agx::Real solution, agx::UInt row, agx::Real h)

virtual void	restoreLightData (agxStream::StorageStream &str) override
	/internal

void	setEnableNonLinearDirectSolveUpdate (agx::Bool enable)
	Enable/disable non-linear update of the friction conditions given current normal force from the direct solver.

void	setFrictionCoefficient (agx::Real frictionCoefficient)
	Assign friction coefficient.

void	setMinimumStaticFrictionForceRange (agx::RangeReal bound)
	Set the minimum force range that this friction controller can apply.

virtual void	storeLightData (agxStream::StorageStream &str) const override
	/internal

Public Member Functions inherited from agx::BasicControllerConstraint
	BasicControllerConstraint (const agx::ConstraintAngleBasedData &data, agx::Bool enable)
	Construct given data containing angle and default enable flag.

	AGXSTREAM_DECLARE_ABSTRACT_SERIALIZABLE (agx::BasicControllerConstraint)

Public Member Functions inherited from agx::ElementaryConstraintNData< 1, ConstraintAngleBasedData >
	ElementaryConstraintNData (const ConstraintAngleBasedData &data, agx::Bool enable)
	Construct given data and enable flag.

ConstraintAngleBasedData &	getData ()

const ConstraintAngleBasedData &	getData () const

virtual void	setAttachmentPair (const agx::AttachmentPair *ap) override
	Data has to support assignment of attachment pair.

Public Member Functions inherited from agx::ElementaryConstraintN< N >
	ElementaryConstraintN (agx::Bool enable)
	Construct given enable flag.

Public Member Functions inherited from agx::ElementaryConstraint
	AGXSTREAM_DECLARE_ABSTRACT_SERIALIZABLE (agx::ElementaryConstraint)

void	copyRowFrom (const ElementaryConstraint *source, agx::UInt sourceRow, agx::UInt destRow)
	Copy configuration row from the given ElementaryConstraint into `this`.

virtual agx::UInt	getBounds (agx::RangeReal *bounds, agx::UInt row, agx::Real h) const
	Returns the bounds of the Lagrange Multipliers (default (-inf, +inf)).

agx::Real	getCompliance (agx::UInt row=0) const

virtual agx::Real	getCurrentForce (const agx::UInt row=0) const
	Returns the force applied last time step by this elementary constraint.

const agx::Real *	getCurrentForces () const

agx::Real	getDamping (agx::UInt row=0) const

agx::Real	getElasticity (agx::UInt row=0) const

virtual agx::Bool	getEnable () const

agx::RangeReal &	getForceRange (const agx::UInt row=0)

const agx::RangeReal &	getForceRange (const agx::UInt row=0) const

virtual agx::UInt	getJacobian (agx::Jacobian6DOFElement *G, agx::UInt numBlocks, agx::UInt row, agx::GWriteState::Enum writeState)
	Returns the Jacobian of this elementary constraint.

const agx::ElementaryConstraint::NameType &	getName () const

virtual agx::ConstraintNlmcpCallback *	getNlCallback () const

agx::UInt	getNumRows () const

agx::RegularizationParameters *	getRegularizationParameters (const agx::UInt row=0)

const agx::RegularizationParameters *	getRegularizationParameters (const agx::UInt row=0) const

virtual agx::UInt	getVelocity (agx::Real *v, agx::UInt row) const
	Returns the velocity of this elementary constraint (extra, driving term on the right hand side).

virtual agx::UInt	getViolation (agx::Real *g, agx::UInt row)
	Returns the violation of this elementary constraint.

virtual agx::Bool	isActive () const
	An elementary constraint is defined to be `active` if enabled.

virtual agx::Bool	isImpacting () const

virtual void	linearizeCompliance (const agx::Real violations, agx::Real epsilons, agx::Real minPerturbation) const
	Modify epsilon so that this ElementaryConstraint appear to be linear in the "normal" deformantion space instead any other space that the ElementaryConstraint may be using.

virtual agx::UInt	postSolveCallback (const agx::Real *solution, agx::UInt row, agx::Real h)
	Callback after solve, with the solution.

virtual void	prepare ()
	Prepare call.

void	reset ()
	Reset call.

virtual void	restore (agxStream::InputArchive &in) override
	Restore this object from stream.

virtual void	restoreLightData (agxStream::StorageStream &str) override
	Restore structural independent data from stream.

virtual void	setAttachmentPair (const agx::AttachmentPair *ap)
	Call for elementary constraints dependent on attachment pairs.

void	setCompliance (agx::Real compliance)

void	setCompliance (agx::Real compliance, int row)
	Assign compliance for a given row, or all rows if `row` = -1 (default).

void	setDamping (agx::Real damping)

void	setDamping (agx::Real damping, int row)
	Assign damping for a given row, or all rows if `row` = -1 (default).

void	setElasticity (agx::Real elasticity)

void	setElasticity (agx::Real elasticity, int row)
	Assign elasticity for a given row, or all rows if `row` = -1 (default).

virtual void	setEnable (agx::Bool enable)
	Enable/disable this elementary constraint.

void	setForceRange (agx::RangeReal forceRange, const agx::UInt row=0)
	Assign force range to a given row.

void	setForceRange (agx::Real lower, agx::Real upper, const agx::UInt row=0)
	Assign force range to a given row.

void	setName (const agx::ElementaryConstraint::NameType &name)
	Name this elementary constraint.

virtual void	store (agxStream::OutputArchive &out) const override
	Store this object to stream.

virtual void	storeLightData (agxStream::StorageStream &str) const override
	Store structural independent data to stream.

Public Member Functions inherited from agx::Referenced
	Referenced ()
	Default constructor.

	Referenced (const Referenced &)

template<typename T >
T *	as ()
	Subclass casting.

template<typename T >
const T *	as () const

template<typename T >
T *	asSafe ()
	Safe subclass casting, return nullptr if template type does not match.

template<typename T >
const T *	asSafe () const

int	getReferenceCount () const

template<typename T >
bool	is () const
	Subclass test.

Referenced &	operator= (const Referenced &)
	Assignment operator. Will increment the number of references to the referenced object.

void	reference (void *ptr=nullptr) const
	Explicitly increment the reference count by one, indicating that this object has another pointer which is referencing it.

void	unreference (void *ptr=nullptr) const
	Decrement the reference count by one, indicating that a pointer to this object is referencing it.

void	unreference_nodelete () const
	Decrement the reference count by one, indicating that a pointer to this object is referencing it.

Public Member Functions inherited from agxStream::Serializable
virtual	~Serializable ()
	Destructor for normal C++ use but hidden from SWIG bindings.

virtual const char *	getClassName () const

bool	getEnableSerialization () const

bool	getEnableUuidGeneration ()

agx::UInt32	getIndex () const
	This index is given at creation of this object.

virtual StorageAgent *	getStorageAgent () const =0

agx::Uuid	getUuid () const

bool	isFinished () const

void	setEnableSerialization (bool flag)
	Set to false to disable serialization of this object.

void	setFinished ()
	Tells this class that it is restored correctly and should not be deleted during destruction of an Archive.

void	setUuid (const agx::Uuid &uuid)
	Explicitly set a Uuid on a serializable object.

Static Public Member Functions
static agxStream::Serializable *	create (agxStream::InputArchive &)

static agx::FrictionController *	safeCast (const agx::ElementaryConstraint *frictionController)
	Utility cast method.

Static Public Member Functions inherited from agx::Referenced
template<typename T >
static bool	ValidateCast (const Referenced *object)

Static Public Member Functions inherited from agxStream::Serializable
static void	setEnableUuidGeneration (bool flag)
	Specify if there should be UUID:s generated for each new Serializable object. By default it is enabled.

Protected Member Functions
	FrictionController ()

virtual	~FrictionController ()

virtual agx::UInt	getBounds (agx::RangeReal *bounds, agx::UInt row, agx::Real h) const override
	Returns the bounds of the Lagrange Multipliers (default (-inf, +inf)).

virtual agx::UInt	getViolation (agx::Real *g, agx::UInt row) override
	Returns the violation of this elementary constraint.

virtual agx::UInt	postSolveCallback (const agx::Real *solution, agx::UInt row, agx::Real h) override
	Callback after solve, with the solution.

Protected Member Functions inherited from agx::BasicControllerConstraint
	BasicControllerConstraint ()
	Used during serialization restore.

virtual agx::UInt	getJacobian (agx::Jacobian6DOFElement *G, agx::UInt numBlocks, agx::UInt row, agx::GWriteState::Enum writeState) override
	Default constraint callback for writing Jacobian.

virtual void	restore (agxStream::InputArchive &in) override
	Restore this object from stream.

virtual void	store (agxStream::OutputArchive &out) const override
	Store this object to stream.

virtual agx::UInt	writeJacobian (agx::Jacobian6DOFElement *G, agx::UInt numBlocks, agx::UInt row, agx::GWriteState::Enum writeState, const agx::Vec3 &dir1, const agx::Vec3 &dir2, agx::Angle::Type type) const
	Internal utility method to write the Jacobian given direction and angle type.

Protected Member Functions inherited from agx::ElementaryConstraintNData< 1, ConstraintAngleBasedData >
	ElementaryConstraintNData ()

Protected Member Functions inherited from agx::ElementaryConstraintN< N >
	ElementaryConstraintN ()
	Used during serialization restore.

Protected Member Functions inherited from agx::ElementaryConstraint
	ElementaryConstraint (agx::Bool enable, agx::UInt numRows, agx::RegularizationParameters regParamsBuffer, agx::Real lastForcesBuffer, agx::RangeReal *userBoundsBuffer)
	Construct given data.

virtual	~ElementaryConstraint ()
	Reference counted object, protected destructor.

Protected Member Functions inherited from agx::Referenced
virtual	~Referenced ()
	Destructor.

void	allocateObserverVector () const

void	deleteUsingDeleteHandler () const

Protected Member Functions inherited from agxStream::Serializable
	Serializable ()
	Default constructor.

	Serializable (const Serializable &other)
	Copy constructor.

void	generateUuid ()

Additional Inherited Members
Public Types inherited from agx::ElementaryConstraint
typedef agx::Name	NameType

typedef agx::VectorPOD< agx::ElementaryConstraint * >	PtrContainer

typedef agx::Vector< agx::ref_ptr< agx::ElementaryConstraint > >	RefContainer

Static Protected Member Functions inherited from agx::Referenced
static DeleteHandler *	getDeleteHandler ()

static void	setDeleteHandler (DeleteHandler *handler)
	Internal: Set a DeleteHandler to which deletion of all referenced counted objects will be delegated to.

Protected Attributes inherited from agx::ElementaryConstraintNData< 1, ConstraintAngleBasedData >
ConstraintAngleBasedData	m_data
	Data.

Protected Attributes inherited from agx::ElementaryConstraintN< N >
agx::RangeReal	m_bounds [N]
	Bounds buffer.

agx::Real	m_forces [N]
	Forces buffer.

agx::RegularizationParameters	m_regParams [N]
	Regularization parameters buffer.

Protected Attributes inherited from agx::ElementaryConstraint
agx::Bool	m_enable
	enabled

agx::ref_ptr< agx::Referenced >	m_internalData
	custom, internal data

agx::Real *	m_lfs
	last forces

agx::ElementaryConstraint::NameType	m_name
	name

agx::UInt	m_numRows
	number of rows

agx::RegularizationParameters *	m_rps
	regularization parameters

agx::RangeReal *	m_ubs
	user bounds

Protected Attributes inherited from agx::Referenced
Mutex	m_mutex

ObserverContainer	m_observers

AtomicValue	m_refCount

Detailed Description

Translational or rotational friction controller for Hinge, Prismatic and CylindricalJoint.

Definition at line 812 of file ElementaryConstraint.h.

Constructor & Destructor Documentation

◆ FrictionController() [1/2]

agx::FrictionController::FrictionController ( const agx::ConstraintAngleBasedData & data )

Construct given angle based data.

This controller is by default disabled.

◆ FrictionController() [2/2]

agx::FrictionController::FrictionController ( )

protected

◆ ~FrictionController()

virtual agx::FrictionController::~FrictionController ( )

protectedvirtual

Member Function Documentation

◆ AGXSTREAM_DECLARE_SERIALIZABLE_BASE()

agx::FrictionController::AGXSTREAM_DECLARE_SERIALIZABLE_BASE ( agx::FrictionController )

◆ create()

static agxStream::Serializable * agx::FrictionController::create ( agxStream::InputArchive & )

inlinestatic

Definition at line 880 of file ElementaryConstraint.h.

◆ getBounds()

virtual agx::UInt agx::FrictionController::getBounds	(	agx::RangeReal *	bounds,
		agx::UInt	row,
		agx::Real	h
	)		const

overrideprotectedvirtual

Returns the bounds of the Lagrange Multipliers (default (-inf, +inf)).

Note that the bounds buffer has to be provided by the caller.

Note: Dimension of the Lagrange Multipliers are Force * Time (argument h = time step length).

Parameters

bounds	- bounds buffer
row	- start row in bounds buffer `bounds`
h	- current time step length

Returns: the number of rows used (= elements written) in the bounds buffer

Reimplemented from agx::ElementaryConstraint.

◆ getEnableNonLinearDirectSolveUpdate()

agx::Bool agx::FrictionController::getEnableNonLinearDirectSolveUpdate ( ) const

Returns: true if non-linear direct solve update is enabled - otherwise false

◆ getFrictionCoefficient()

agx::Real agx::FrictionController::getFrictionCoefficient ( ) const

Returns: the friction coefficient

◆ getMinimumStaticFrictionForceRange()

agx::RangeReal agx::FrictionController::getMinimumStaticFrictionForceRange ( ) const

Get the minimum force range that this friction controller can apply.

See also: setMinimumStaticFrictionForceRange

◆ getNlCallback()

ConstraintNlmcpCallback * agx::FrictionController::getNlCallback ( ) const

overridevirtual

Returns: solver callback instance if supported by this elementary constraint

Reimplemented from agx::ElementaryConstraint.

◆ getViolation()

virtual agx::UInt agx::FrictionController::getViolation	(	agx::Real *	g,
		agx::UInt	row
	)

overrideprotectedvirtual

Returns the violation of this elementary constraint.

Note that the violation buffer has to be provided by the caller.

Parameters

g	- violation buffer
row	- start row in violation buffer g

Returns: the number of rows used (= elements written) in violation buffer

Reimplemented from agx::ElementaryConstraint.

◆ isActive()

virtual agx::Bool agx::FrictionController::isActive ( ) const

overridevirtual

Returns: true when this controller is enabled and has a friction coefficient larger than zero - otherwise false

Reimplemented from agx::ElementaryConstraint.

◆ iterativePostSolveCallback()

agx::UInt agx::FrictionController::iterativePostSolveCallback	(	const agx::ConstraintImplementation *	constraint,
		const agx::Real *	solution,
		agx::UInt	row,
		agx::Real	h
	)

◆ postSolveCallback()

virtual agx::UInt agx::FrictionController::postSolveCallback	(	const agx::Real *	solution,
		agx::UInt	row,
		agx::Real	h
	)

overrideprotectedvirtual

Callback after solve, with the solution.

Parameters

solution	- solution of the last solve
row	- start row in solution for this elementary constraint
h	- current time step length

Returns: number of rows read (= number of rows of this elementary constraint)

Reimplemented from agx::ElementaryConstraint.

◆ restoreLightData()

virtual void agx::FrictionController::restoreLightData ( agxStream::StorageStream & str )

overridevirtual

/internal

Restore structural independent data from stream.

Reimplemented from agx::ElementaryConstraint.

◆ safeCast()

static agx::FrictionController * agx::FrictionController::safeCast ( const agx::ElementaryConstraint * frictionController )

static

Utility cast method.

◆ setEnableNonLinearDirectSolveUpdate()

void agx::FrictionController::setEnableNonLinearDirectSolveUpdate ( agx::Bool enable )

Enable/disable non-linear update of the friction conditions given current normal force from the direct solver.

When enabled - this feature is similar to scale box friction models with solve type DIRECT.

Default: Disabled

Note: This feature only supports constraint solve types DIRECT and DIRECT_AND_ITERATIVE - meaning, if the constraint has solve type ITERATIVE, this feature is ignored.

Parameters

enable - true to enable, false to disable (Disabled by default.)

◆ setFrictionCoefficient()

void agx::FrictionController::setFrictionCoefficient ( agx::Real frictionCoefficient )

Assign friction coefficient.

Default: 0.4167.

Note: If this controller is rotational (Hinge or CylindriclJoint) the radius of the axle should be included in the friction coefficient for the comparisons with the normal force to be dimensionally correct. I.e., friction_torque <= friction_coefficient * axle_radius * normal_force

Parameters

frictionCoefficient - friction coefficient

◆ setMinimumStaticFrictionForceRange()

void agx::FrictionController::setMinimumStaticFrictionForceRange ( agx::RangeReal bound )

Set the minimum force range that this friction controller can apply.

Can be used to simulate static friction. Default: (0, 0)

◆ storeLightData()

virtual void agx::FrictionController::storeLightData ( agxStream::StorageStream & str ) const

overridevirtual

/internal

Store structural independent data to stream.

Reimplemented from agx::ElementaryConstraint.

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

ElementaryConstraint.h

Public Member Functions

Static Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ FrictionController() [1/2]

◆ FrictionController() [2/2]

◆ ~FrictionController()

Member Function Documentation

◆ AGXSTREAM_DECLARE_SERIALIZABLE_BASE()

◆ create()

◆ getBounds()

◆ getEnableNonLinearDirectSolveUpdate()

◆ getFrictionCoefficient()

◆ getMinimumStaticFrictionForceRange()

◆ getNlCallback()

◆ getViolation()

◆ isActive()

◆ iterativePostSolveCallback()

◆ postSolveCallback()

◆ restoreLightData()

◆ safeCast()

◆ setEnableNonLinearDirectSolveUpdate()

◆ setFrictionCoefficient()

◆ setMinimumStaticFrictionForceRange()

◆ storeLightData()