dart::constraint::BallJointConstraint Class Reference

BallJointConstraint represents ball joint constraint between a body and the world or between two bodies. More...

#include <BallJointConstraint.hpp>

Inheritance diagram for dart::constraint::BallJointConstraint:

Public Member Functions
	BallJointConstraint (dynamics::BodyNode *_body, const Eigen::Vector3d &_jointPos)
	Constructor that takes one body and the joint position in the world frame.
	BallJointConstraint (dynamics::BodyNode *_body1, dynamics::BodyNode *_body2, const Eigen::Vector3d &_jointPos)
	Constructor that takes two bodies and the joint position in the frame of _body1.
virtual	~BallJointConstraint ()
	Destructor.
const std::string &	getType () const override
	Returns a string representing the constraint type.
dynamics::BodyNode *	getBodyNode1 () const
	Get the first BodyNode that this constraint is associated with.
dynamics::BodyNode *	getBodyNode2 () const
	Get the second BodyNode that this constraint is associated with.
std::size_t	getDimension () const
	Return dimesion of this constranit.

Static Public Member Functions
static const std::string &	getStaticType ()
	Returns constraint type for this class.
static void	setErrorAllowance (double _allowance)
	Set global error reduction parameter.
static double	getErrorAllowance ()
	Get global error reduction parameter.
static void	setErrorReductionParameter (double _erp)
	Set global error reduction parameter.
static double	getErrorReductionParameter ()
	Get global error reduction parameter.
static void	setMaxErrorReductionVelocity (double _erv)
	Set global error reduction parameter.
static double	getMaxErrorReductionVelocity ()
	Get global error reduction parameter.
static void	setConstraintForceMixing (double _cfm)
	Set global constraint force mixing parameter.
static double	getConstraintForceMixing ()
	Get global constraint force mixing parameter.
static dynamics::SkeletonPtr	getRootSkeleton (dynamics::SkeletonPtr skeleton)
static dynamics::SkeletonPtr	compressPath (dynamics::SkeletonPtr skeleton)

Protected Member Functions
void	update () override
	Update constraint using updated Skeleton's states.
void	getInformation (ConstraintInfo *_lcp) override
	Fill LCP variables.
void	applyUnitImpulse (std::size_t _index) override
	Apply unit impulse to constraint space.
void	getVelocityChange (double *_vel, bool _withCfm) override
	Get velocity change due to the uint impulse.
void	excite () override
	Excite the constraint.
void	unexcite () override
	Unexcite the constraint.
void	applyImpulse (double *_lambda) override
	Apply computed constraint impulse to constrained skeletons.
bool	isActive () const override
	Return true if this constraint is active.
dynamics::SkeletonPtr	getRootSkeleton () const override
void	uniteSkeletons () override

Protected Attributes
dynamics::BodyNode *	mBodyNode1
	First body node.
dynamics::BodyNode *	mBodyNode2
	Second body node.
std::size_t	mDim
	Dimension of constraint.

Static Protected Attributes
static double	mErrorAllowance = 0.0
	Global constraint error allowance.
static double	mErrorReductionParameter = 0.01
	Global constraint error redection parameter in the range of [0, 1].
static double	mMaxErrorReductionVelocity = 1e+1
	Maximum error reduction velocity.
static double	mConstraintForceMixing = 1e-9
	Global constraint force mixing parameter in the range of [1e-9, 1].

Private Attributes
Eigen::Vector3d	mOffset1
	Offset from the origin of body frame 1 to the ball joint position where the offset is expressed in body frame 1.
Eigen::Vector3d	mOffset2
	Offset from the origin of body frame 2 to the ball joint position where the offset is expressed in body frame 2.
Eigen::Vector3d	mViolation
	Position constraint violation expressed in body frame 1.
Eigen::Matrix< double, 3, 6 >	mJacobian1
	Linear map between constraint space and Cartesian space for body1.
Eigen::Matrix< double, 3, 6 >	mJacobian2
	Linear map between constraint space and Cartesian space for body2.
double	mOldX [3]
std::size_t	mAppliedImpulseIndex
	Index of applied impulse.

Detailed Description

BallJointConstraint represents ball joint constraint between a body and the world or between two bodies.

Constructor & Destructor Documentation

BallJointConstraint() [1/2]

dart::constraint::BallJointConstraint::BallJointConstraint	(	dynamics::BodyNode *	_body,
		const Eigen::Vector3d &	_jointPos
	)

Constructor that takes one body and the joint position in the world frame.

Parameters

[in]	_body
[in]	_jointPos	Joint position expressed in world frame

BallJointConstraint() [2/2]

dart::constraint::BallJointConstraint::BallJointConstraint	(	dynamics::BodyNode *	_body1,
		dynamics::BodyNode *	_body2,
		const Eigen::Vector3d &	_jointPos
	)

Constructor that takes two bodies and the joint position in the frame of _body1.

Parameters

[in]	_body1
[in]	_body2
[in]	_jointPos	Joint position expressed in world frame

~BallJointConstraint()

dart::constraint::BallJointConstraint::~BallJointConstraint ( )

virtual

Destructor.

Member Function Documentation

applyImpulse()

void dart::constraint::BallJointConstraint::applyImpulse ( double *  lambda )

overrideprotectedvirtual

Apply computed constraint impulse to constrained skeletons.

Implements dart::constraint::ConstraintBase.

applyUnitImpulse()

void dart::constraint::BallJointConstraint::applyUnitImpulse ( std::size_t  index )

overrideprotectedvirtual

Apply unit impulse to constraint space.

Implements dart::constraint::ConstraintBase.

compressPath()

dynamics::SkeletonPtr dart::constraint::ConstraintBase::compressPath ( dynamics::SkeletonPtr  skeleton )

staticinherited

excite()

void dart::constraint::BallJointConstraint::excite ( )

overrideprotectedvirtual

Excite the constraint.

Implements dart::constraint::ConstraintBase.

getBodyNode1()

dynamics::BodyNode * dart::constraint::JointConstraint::getBodyNode1 ( ) const

inherited

Get the first BodyNode that this constraint is associated with.

getBodyNode2()

dynamics::BodyNode * dart::constraint::JointConstraint::getBodyNode2 ( ) const

inherited

Get the second BodyNode that this constraint is associated with.

getConstraintForceMixing()

double dart::constraint::JointConstraint::getConstraintForceMixing ( )

staticinherited

Get global constraint force mixing parameter.

getDimension()

std::size_t dart::constraint::ConstraintBase::getDimension ( ) const

inherited

Return dimesion of this constranit.

getErrorAllowance()

double dart::constraint::JointConstraint::getErrorAllowance ( )

staticinherited

Get global error reduction parameter.

getErrorReductionParameter()

double dart::constraint::JointConstraint::getErrorReductionParameter ( )

staticinherited

Get global error reduction parameter.

getInformation()

void dart::constraint::BallJointConstraint::getInformation ( ConstraintInfo *  info )

overrideprotectedvirtual

Fill LCP variables.

Implements dart::constraint::ConstraintBase.

getMaxErrorReductionVelocity()

double dart::constraint::JointConstraint::getMaxErrorReductionVelocity ( )

staticinherited

Get global error reduction parameter.

getRootSkeleton() [1/2]

dynamics::SkeletonPtr dart::constraint::BallJointConstraint::getRootSkeleton ( ) const

overrideprotectedvirtual

Implements dart::constraint::ConstraintBase.

getRootSkeleton() [2/2]

dynamics::SkeletonPtr dart::constraint::ConstraintBase::getRootSkeleton ( dynamics::SkeletonPtr  skeleton )

staticinherited

getStaticType()

const std::string & dart::constraint::BallJointConstraint::getStaticType ( )

static

Returns constraint type for this class.

getType()

const std::string & dart::constraint::BallJointConstraint::getType ( ) const

overridevirtual

Returns a string representing the constraint type.

Reimplemented from dart::constraint::ConstraintBase.

getVelocityChange()

void dart::constraint::BallJointConstraint::getVelocityChange ( double *  vel, bool  withCfm  )

overrideprotectedvirtual

Get velocity change due to the uint impulse.

Implements dart::constraint::ConstraintBase.

isActive()

bool dart::constraint::BallJointConstraint::isActive ( ) const

overrideprotectedvirtual

Return true if this constraint is active.

Implements dart::constraint::ConstraintBase.

setConstraintForceMixing()

void dart::constraint::JointConstraint::setConstraintForceMixing ( double  _cfm )

staticinherited

Set global constraint force mixing parameter.

setErrorAllowance()

void dart::constraint::JointConstraint::setErrorAllowance ( double  _allowance )

staticinherited

Set global error reduction parameter.

setErrorReductionParameter()

void dart::constraint::JointConstraint::setErrorReductionParameter ( double  _erp )

staticinherited

Set global error reduction parameter.

setMaxErrorReductionVelocity()

void dart::constraint::JointConstraint::setMaxErrorReductionVelocity ( double  _erv )

staticinherited

Set global error reduction parameter.

unexcite()

void dart::constraint::BallJointConstraint::unexcite ( )

overrideprotectedvirtual

Unexcite the constraint.

Implements dart::constraint::ConstraintBase.

uniteSkeletons()

void dart::constraint::BallJointConstraint::uniteSkeletons ( )

overrideprotectedvirtual

Reimplemented from dart::constraint::ConstraintBase.

update()

void dart::constraint::BallJointConstraint::update ( )

overrideprotectedvirtual

Update constraint using updated Skeleton's states.

Implements dart::constraint::ConstraintBase.

Member Data Documentation

mAppliedImpulseIndex

std::size_t dart::constraint::BallJointConstraint::mAppliedImpulseIndex

private

Index of applied impulse.

mBodyNode1

dynamics::BodyNode* dart::constraint::JointConstraint::mBodyNode1

protectedinherited

First body node.

mBodyNode2

dynamics::BodyNode* dart::constraint::JointConstraint::mBodyNode2

protectedinherited

Second body node.

mConstraintForceMixing

double dart::constraint::JointConstraint::mConstraintForceMixing = 1e-9

staticprotectedinherited

Global constraint force mixing parameter in the range of [1e-9, 1].

The default is 1e-5

See also

http://www.ode.org/ode-latest-userguide.html#sec_3_8_0

mDim

std::size_t dart::constraint::ConstraintBase::mDim

protectedinherited

Dimension of constraint.

mErrorAllowance

double dart::constraint::JointConstraint::mErrorAllowance = 0.0

staticprotectedinherited

Global constraint error allowance.

mErrorReductionParameter

double dart::constraint::JointConstraint::mErrorReductionParameter = 0.01

staticprotectedinherited

Global constraint error redection parameter in the range of [0, 1].

The default is 0.01.

mJacobian1

Eigen::Matrix<double, 3, 6> dart::constraint::BallJointConstraint::mJacobian1

private

Linear map between constraint space and Cartesian space for body1.

mJacobian2

Eigen::Matrix<double, 3, 6> dart::constraint::BallJointConstraint::mJacobian2

private

Linear map between constraint space and Cartesian space for body2.

mMaxErrorReductionVelocity

double dart::constraint::JointConstraint::mMaxErrorReductionVelocity = 1e+1

staticprotectedinherited

Maximum error reduction velocity.

mOffset1

Eigen::Vector3d dart::constraint::BallJointConstraint::mOffset1

private

Offset from the origin of body frame 1 to the ball joint position where the offset is expressed in body frame 1.

mOffset2

Eigen::Vector3d dart::constraint::BallJointConstraint::mOffset2

private

Offset from the origin of body frame 2 to the ball joint position where the offset is expressed in body frame 2.

mOldX

double dart::constraint::BallJointConstraint::mOldX[3]

private

mViolation

Eigen::Vector3d dart::constraint::BallJointConstraint::mViolation

private

Position constraint violation expressed in body frame 1.