The hinge constraint between two rigid bodies or one rigid body and the world. More...

#include <Hinge.h>

Inheritance diagram for agx::Hinge:

Public Types
enum	DOF { ALL_DOF =-1 , TRANSLATIONAL_1 =0 , TRANSLATIONAL_2 =1 , TRANSLATIONAL_3 =2 , ROTATIONAL_1 =3 , ROTATIONAL_2 =4 , NUM_DOF =5 }
	Enum used for specifying which Degree of Freedom (DOF) that should be accessed in calls to for example: constraint->getRegularizationParameters( dof ); constraint->setDamping( damping, dof );. More...

Public Types inherited from agx::Constraint
enum	SolveType { DIRECT = 1 , ITERATIVE = (1<<2) , DIRECT_AND_ITERATIVE = (DIRECT \| ITERATIVE) }
	Specifies in what solvers the constraint will be solved. More...

Public Member Functions
	Hinge ()
	Default constructor.

	Hinge (const HingeFrame &hf, RigidBody rb1, RigidBody rb2=0)
	Create hinge given a hinge frame (world coordinates) and one or two rigid bodies.

	Hinge (RigidBody rb1, Frame rb1AttachmentFrame, RigidBody rb2=nullptr, Frame rb2AttachmentFrame=nullptr)
	Create hinge given attachment frames and one or two rigid bodies.

bool	addRigidBody (RigidBody rb, Frame rbAttachmentFrame)
	Create hinge given attachment frame and one body at the time.

	AGXSTREAM_DECLARE_SERIALIZABLE_BASE (agx::Hinge)

int	getNumDOF () const override

Public Member Functions inherited from agx::Constraint1DOF
agx::Real	getAngle () const
	This method return the current angle for the 1D constraint.

agx::Real	getCurrentSpeed () const
	This methods return the current speed for the 1D constraint.

agx::ElectricMotorController *	getElectricMotorController ()

const agx::ElectricMotorController *	getElectricMotorController () const

agx::FrictionController *	getFrictionController ()

const agx::FrictionController *	getFrictionController () const

agx::Lock1D *	getLock1D ()

const agx::Lock1D *	getLock1D () const

agx::Motor1D *	getMotor1D ()

const agx::Motor1D *	getMotor1D () const

agx::Range1D *	getRange1D ()

const agx::Range1D *	getRange1D () const

Public Member Functions inherited from agx::Constraint
agx::Bool	addElementaryConstraint (const agx::Name &name, agx::ElementaryConstraint *elementaryConstraint)
	Add elementary constraint (like Spherical, Dot1, Dot2 etc) given name.

agx::Bool	addSecondaryConstraint (const agx::Name &name, agx::ElementaryConstraint *secondaryConstraint)
	Add secondary constraint (like motor, range and/or lock etc) given name.

	AGXSTREAM_DECLARE_ABSTRACT_SERIALIZABLE (agx::Constraint)

template<typename T >
T *	as ()
	Try to do dynamic_cast on the constraint and return a pointer to the casted constraint.

template<typename T >
const T *	as () const
	Try to do dynamic_cast on the constraint and return a pointer to the casted constraint.

RealVector	calculateCurrentViolation () const
	Calculates the current violation of the ordinary degrees of freedom of this constraint, e.g., three translational and two rotational (total 5 elements) of a hinge, i.e., controllers DOF are not included.

agx::UInt	calculateNumActiveRows () const
	Calculates the current number of active rows, including both elementary and secondary constraints.

template<typename T >
ref_ptr< T >	createFromBody (Vec3 bodyPoint, Vec3 bodyAxis, RigidBody rb1, RigidBody rb2)

template<typename T >
ref_ptr< T >	createFromWorld (Vec3 worldPoint, Vec3 worldAxis, RigidBody rb1, RigidBody rb2)

agx::Attachment *	getAttachment (agx::UInt i) const

agx::RigidBodyAttachment *	getAttachment (const agx::RigidBody *rb) const

agx::AttachmentPair *	getAttachmentPair () const

agx::RigidBody *	getBodyAt (agx::UInt i)

const agx::RigidBody *	getBodyAt (agx::UInt i) const

virtual agx::Real	getCompliance (agx::UInt dof) const
	Get the compliance for DOF i.

agx::Real	getCurrentForce (agx::UInt dof) const
	Consider using `getLastForce` instead.

virtual Real	getDamping (agx::UInt dof) const
	Get the damping for DOF `dof`.

virtual agx::Real	getElasticity (agx::UInt dof) const
	Get the elasticity for DOF i.

agx::ElementaryConstraint *	getElementaryConstraint (const agx::UInt index) const

agx::ElementaryConstraint *	getElementaryConstraintGivenName (const agx::Name &name) const
	Find elementary constraint given name.

agx::Bool	getEnable () const

agx::Bool	getEnableComputeForces () const

bool	getEnableDebugRendering () const

bool	getEnableLinearization () const

agx::UInt32	getEntityId () const

agx::RangeReal	getForceRange (agx::UInt dof=0) const
	Get the force range for DOF `dof`.

agx::Bool	getLastForce (agx::UInt bodyIndex, agx::Vec3 &retForce, agx::Vec3 &retTorque, agx::Bool giveForceAtCm=false) const
	If 'compute forces' is enabled, returns the last force and torque applied by this constraint on the body with `bodyIndex`.

agx::Bool	getLastForce (const agx::RigidBody *rb, agx::Vec3 &retForce, agx::Vec3 &retTorque, agx::Bool giveForceAtCm=false) const
	If 'compute forces' is enabled, returns the last force and torque applied by this constraint on the body `rb`.

agx::Bool	getLastLocalForce (agx::UInt bodyIndex, agx::Vec3 &retForce, agx::Vec3 &retTorque, agx::Bool giveForceAtCm=false) const
	If 'compute forces' is enabled, returns the last force and torque applied by this constraint on the body with `bodyIndex`.

agx::Bool	getLastLocalForce (const agx::RigidBody *rb, agx::Vec3 &retForce, agx::Vec3 &retTorque, agx::Bool giveForceAtCm=false) const
	If 'compute forces' is enabled, returns the last force and torque applied by this constraint on the body `rb`.

agx::UInt	getNumBodies () const
	returns the number of bodies involved

virtual int	getNumDOF () const =0

agx::UInt	getNumElementaryConstraints () const

agx::UInt	getNumSecondaryConstraints () const

virtual agx::RegularizationParameters *	getRegularizationParameters (agx::UInt i)

virtual const agx::RegularizationParameters *	getRegularizationParameters (agx::UInt i) const

agx::ConstraintImplementation *	getRep ()

const agx::ConstraintImplementation *	getRep () const

agx::ElementaryConstraint *	getSecondaryConstraint (const agx::UInt index) const

agx::ElementaryConstraint *	getSecondaryConstraintGivenName (const agx::Name &name) const
	Find secondary constraint given name.

agx::Constraint::SolveType	getSolveType () const

agx::Bool	getValid () const

agx::Bool	isEnabled () const

virtual agx::Bool	rebind ()
	Rebind this constraint, i.e., use current state as the initial configuration.

agx::Bool	removeElementaryConstraint (agx::ElementaryConstraint *elementaryConstraint)
	Remove elementary constraint.

agx::Bool	removeElementaryConstraint (const agx::Name &name)
	Remove elementary constraint.

agx::Bool	removeSecondaryConstraint (agx::ElementaryConstraint *secondaryConstraint)
	Remove secondary constraint.

agx::Bool	removeSecondaryConstraint (const agx::Name &name)
	Remove secondary constraint.

virtual void	render (class agxRender::RenderManager *mgr, float scale) const =0
	Inherited method of how to render this constraint into DebugRenderer.

void	restore (agxStream::InputArchive &in) override

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

void	setCompliance (agx::Real compliance)
	Set the compliance of this constraint for all DOFs.

virtual void	setCompliance (agx::Real compliance, agx::Int dof)
	Set the compliance of this constraint for the i:th DOF.

void	setDamping (agx::Real damping)
	Set the damping of this constraint for all DOFs.

virtual void	setDamping (agx::Real damping, agx::Int dof)
	Set the damping of this constraint for the i:th DOF.

virtual void	setElasticity (agx::Real elasticity)
	Set the elasticity of this constraint for all DOFs.

virtual void	setElasticity (agx::Real elasticity, agx::Int dof)
	Set the elasticity of this constraint for the i:th DOF.

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

void	setEnableComputeForces (agx::Bool enable)
	Enable (or disable) computation of the forces applied to the dynamic bodies in this constraint.

void	setEnableDebugRendering (agx::Bool enable)
	Enable/disable debug rendering of this constraint.

void	setEnableLinearization (bool enable)
	Pass `true` to enable linearization of constraint compliance.

void	setForceRange (agx::RangeReal forceRange)
	Assign force range for all DOF of the elementary constraints.

void	setForceRange (agx::RangeReal forceRange, agx::Int dof)
	Assign force range, of an elementary constraint, for a given DOF.

void	setForceRange (agx::Real lower, agx::Real upper, agx::Int dof)
	Assign force range, of an elementary constraint, for a given DOF.

void	setSolveType (agx::Constraint::SolveType solveType)
	Specify the solve type for this constraint.

void	store (agxStream::OutputArchive &out) const override

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

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

	AGXSTREAM_DECLARE_SERIALIZABLE_BASE (agx::Interaction)

const agx::Name &	getName () const

agx::PropertyContainer *	getPropertyContainer ()

const agx::PropertyContainer *	getPropertyContainer () const

agxSDK::SimulationProxy *	getSimulationProxy () const

agx::Bool	hasPropertyContainer () const

virtual void	postSystemCallback (agx::DynamicsSystem *)
	Called after all post step events, after solve.

virtual void	preSystemCallback (agx::DynamicsSystem *)
	Called after all pre step events, before solve.

void	setName (const agx::Name &name)
	Name this interaction.

void	setPropertyContainer (agx::PropertyContainer *propertyContainer)
	Assign a new property container.

virtual void	updateForce (agx::DynamicsSystem *dynamicsSystem)
	This virtual method is implemented so that it computes the interaction forces on all the physical bodies implicated.

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 Public Member Functions inherited from agx::Constraint1DOF
static agx::Constraint1DOF *	safeCast (const agx::Constraint *constraint)
	Utility method for not so type safe languages.

Static Public Member Functions inherited from agx::Constraint
static agx::Bool	calculateFramesFromBody (agx::Vec3 bodyPoint, agx::Vec3 bodyAxis, agx::Vec3 secondBodyAxis, const agx::RigidBody body, agx::Frame bodyFrame, const agx::RigidBody otherBody, agx::Frame otherFrame)
	Calculates the constraint attachment frames given point and axes in body coordinates of `body`.

static agx::Bool	calculateFramesFromBody (agx::Vec3 bodyPoint, agx::Vec3 bodyAxis, const agx::RigidBody body, agx::Frame bodyFrame, const agx::RigidBody otherBody, agx::Frame otherFrame)
	Calculates the constraint attachment frames given point and axis in body coordinates of `body`.

static agx::Bool	calculateFramesFromWorld (agx::Vec3 worldPoint, agx::Vec3 worldAxis, agx::Vec3 secondWorldAxis, const agx::RigidBody rb1, agx::Frame rb1Frame, const agx::RigidBody rb2, agx::Frame rb2Frame)
	Given a point and two axes in world, this function calculates each local attachment frame for one or two bodies.

static agx::Bool	calculateFramesFromWorld (agx::Vec3 worldPoint, agx::Vec3 worldAxis, const agx::RigidBody rb1, agx::Frame rb1Frame, const agx::RigidBody rb2, agx::Frame rb2Frame)
	Given a point and an axis in world, this function calculates each local attachment frame for one or two bodies.

template<typename T >
static agx::ref_ptr< T >	createFromBody (agx::Vec3 bodyPoint, agx::Vec3 bodyAxis, agx::RigidBody rb1, agx::RigidBody rb2=nullptr)
	Creates a constraint given a point and an axis in `rb1` model frame.

template<typename T >
static agx::ref_ptr< T >	createFromWorld (agx::Vec3 worldPoint, agx::Vec3 worldAxis, agx::RigidBody rb1, agx::RigidBody rb2=nullptr)
	Creates a constraint given a point and an axis in world frame.

Static Public Member Functions inherited from agx::Interaction
static agxStream::Serializable *	create (agxStream::InputArchive &)

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
virtual	~Hinge ()

virtual void	render (class agxRender::RenderManager *mgr, float scale) const override
	Used internally for debug rendering.

Protected Member Functions inherited from agx::Constraint1DOF
	Constraint1DOF ()

virtual	~Constraint1DOF ()

Protected Member Functions inherited from agx::Constraint
	Constraint ()

virtual	~Constraint ()

virtual void	addNotification () override
	Called when added to a simulation.

virtual void	postSystemCallback (agx::DynamicsSystem *dynamicsSystem) override
	Called after all post step events, after solve.

virtual void	preSystemCallback (agx::DynamicsSystem *dynamicsSystem) override
	Called after all pre step events, before solve.

virtual void	removeNotification () override
	Called when removed from a simulation.

void	setRep (agx::ConstraintImplementation *_rep)

virtual void	setSimulation (agxSDK::Simulation *simulation) override
	Assign simulation.

virtual void	setSystem (agx::DynamicsSystem *)

Protected Member Functions inherited from agx::Interaction
virtual	~Interaction ()
	Reference counted object, protected destructor.

virtual void	addNotification ()
	Called when added to a simulation.

virtual void	removeNotification ()
	Called when removed from a simulation.

virtual void	setSimulation (agxSDK::Simulation *simulation)
	Assign simulation.

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
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::Constraint
agx::ConstraintImplementation *	m_implementation

Protected Attributes inherited from agx::Referenced
Mutex	m_mutex

ObserverContainer	m_observers

AtomicValue	m_refCount

Detailed Description

The hinge constraint between two rigid bodies or one rigid body and the world.

The hinge constraint maintains a constant rotational axis between two rigid bodies and allows rotation about this axis. By default, there is no control on the relative angle between the two bodies and in fact, the relative rotational angle is not computed. By using the DOFController object and setting flags and other parameters, the relative angle can be computed. It can also be limited to a given range, locked at a given value, or motorized using a velocity or a position constraint. When a joint limit is reached, an inequality constraint is added to the system to enforce the joint limit. If the motor or lock control is already turned ON, both constraints can be active, and it is up to the solver to compute the correct solution.

When setting up the hinge constraint, the user can simply pass a HingeFrame object to the constraint. The "Z" axis of the frame will then be used as the hinge axis. This is not to say that the constraint will keep that axis in world coordinates, only that at the instant following configuration, the hinge axis will be coincident with the "Z" axis of the given frame. Correspondingly, by default, the joint angle will be computed in the "XY" plane of the given frame so that zero angle corresponds to the hinge frame aligned along the original "X" axis.

In addition, the configuration of the hinge can be done by setting the attachment frames of each of the bodies. When doing that, the constraint will then operate to make the two "Z" axes parallel, and the origins of the two frames coincident.

Definition at line 103 of file Hinge.h.

Member Enumeration Documentation

◆ DOF

enum agx::Hinge::DOF

Enum used for specifying which Degree of Freedom (DOF) that should be accessed in calls to for example: constraint->getRegularizationParameters( dof ); constraint->setDamping( damping, dof );.

Enumerator
ALL_DOF	Select all degrees of freedom.
TRANSLATIONAL_1	Select DOF for the first translational axis.
TRANSLATIONAL_2	Select DOF for the second translational axis.
TRANSLATIONAL_3	Select DOF for the third translational axis.
ROTATIONAL_1	Select DOF corresponding to the first rotational axis.
ROTATIONAL_2	Select DOF corresponding to the second rotational axis.
NUM_DOF	Number of DOF available for this constraint.

Definition at line 151 of file Hinge.h.

Constructor & Destructor Documentation

◆ Hinge() [1/3]

agx::Hinge::Hinge ( )

Default constructor.

Should be used with the addRigidBody method.

◆ Hinge() [2/3]

agx::Hinge::Hinge	(	const HingeFrame &	hf,
		RigidBody *	rb1,
		RigidBody *	rb2 = `0`
	)

Create hinge given a hinge frame (world coordinates) and one or two rigid bodies.

The hinge axis and attachment point are given in world coordinates.

Parameters

hf	- HingeFrame defining the hinge
rb1	- First body (invalid if null)
rb2	- Second body connected with the hinge (if null, first rigid body will be attached in world)

Note: If this constructor fails to create this constraint, a warning is printed and this constraint is cleared.

◆ Hinge() [3/3]

agx::Hinge::Hinge	(	RigidBody *	rb1,
		Frame *	rb1AttachmentFrame,
		RigidBody *	rb2 = `nullptr`,
		Frame *	rb2AttachmentFrame = `nullptr`
	)

Create hinge given attachment frames and one or two rigid bodies.

The attachment frame is relative its body with the hinge axis pointing in the z-direction of the attachment frame. If rb2 == rb2AttachmentFrame == 0 the first body will be attached to the world given rb1AttachmentFrame. If rb2 == 0 and rb2AttachmentFrame != 0, then rb2AttachmentFrame will be used as the world frame attachment.

Parameters

rb1	- First rigid body (invalid if null)
rb1AttachmentFrame	- First rigid body attachment frame (invalid if null)
rb2	- Second rigid body (if null, first rigid body will be attached in world)
rb2AttachmentFrame	- Second rigid body attachment frame (invalid if rb2 != 0 and this is null)

Note: If this constructor fails to create this constraint, a warning is printed and this constraint is cleared.

◆ ~Hinge()

virtual agx::Hinge::~Hinge ( )

protectedvirtual

Member Function Documentation

◆ addRigidBody()

bool agx::Hinge::addRigidBody	(	RigidBody *	rb,
		Frame *	rbAttachmentFrame
	)

Create hinge given attachment frame and one body at the time.

This is only valid for two bodies, i.e., it's not possible to use this method with bodies attached to the world. When the second body has been added, this constraint will calculate its initial state and is after that ready to be added to the simulation.

Parameters

rb	- Current rigid body to be added to this constraint
rbAttachmentFrame	- Attachment frame of the current rigid body

◆ AGXSTREAM_DECLARE_SERIALIZABLE_BASE()

agx::Hinge::AGXSTREAM_DECLARE_SERIALIZABLE_BASE ( agx::Hinge )

◆ create()

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

inlinestatic

Definition at line 167 of file Hinge.h.

◆ getNumDOF()

int agx::Hinge::getNumDOF ( ) const

overridevirtual

Returns: the number of DOF for this constraint, not including secondary constraints. -1 if num DOF is undefined for the constraint.

Implements agx::Constraint.

◆ render()

virtual void agx::Hinge::render	(	class agxRender::RenderManager *	mgr,
		float	scale
	)		const

overrideprotectedvirtual

Used internally for debug rendering.

Implements agx::Constraint.

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

Hinge.h

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ DOF

Constructor & Destructor Documentation

◆ Hinge() [1/3]

◆ Hinge() [2/3]

◆ Hinge() [3/3]

◆ ~Hinge()

Member Function Documentation

◆ addRigidBody()

◆ AGXSTREAM_DECLARE_SERIALIZABLE_BASE()

◆ create()

◆ getNumDOF()

◆ render()