dart::constraint::SoftContactConstraint Class Reference

SoftContactConstraint represents a contact constraint between two bodies. More...

#include <SoftContactConstraint.hpp>

Inheritance diagram for dart::constraint::SoftContactConstraint:

Public Member Functions
	SoftContactConstraint (collision::Contact &_contact, double _timeStep)
	Constructor.
virtual	~SoftContactConstraint ()
	Destructor.
const std::string &	getType () const override
	Returns a string representing the constraint type.
void	setFrictionDirection (const Eigen::Vector3d &_dir)
	Set first frictional direction.
const Eigen::Vector3d &	getFrictionDirection1 () const
	Get first frictional direction.
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 *_info) override
	Fill LCP variables.
void	applyUnitImpulse (std::size_t _idx) 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.
dynamics::SkeletonPtr	getRootSkeleton () const override
void	uniteSkeletons () override
bool	isActive () const override
	Return true if this constraint is active.

Static Protected Member Functions
static double	computeFrictionCoefficient (const dynamics::ShapeNode *shapeNode)
static double	computeRestitutionCoefficient (const dynamics::ShapeNode *shapeNode)

Protected Attributes
std::size_t	mDim
	Dimension of constraint.

Private Member Functions
void	getRelVelocity (double *_vel)
	Get change in relative velocity at contact point due to external impulse.
void	updateFirstFrictionalDirection ()
Eigen::MatrixXd	getTangentBasisMatrixODE (const Eigen::Vector3d &_n)
dynamics::PointMass *	selectCollidingPointMass (dynamics::SoftBodyNode *_softBodyNode, const Eigen::Vector3d &_point, int _faceId) const
	Find the nearest point mass from _point in a face, of which id is _faceId in _softBodyNode.
const dynamics::PointMass *	selectCollidingPointMass (const dynamics::SoftBodyNode *_softBodyNode, const Eigen::Vector3d &_point, int _faceId) const
	Find the nearest point mass from _point in a face, of which id is _faceId in _softBodyNode.

Private Attributes
double	mTimeStep
	Time step.
dynamics::BodyNode *	mBodyNode1
	Fircst body node.
dynamics::BodyNode *	mBodyNode2
	Second body node.
dynamics::SoftBodyNode *	mSoftBodyNode1
	First soft body node.
dynamics::SoftBodyNode *	mSoftBodyNode2
	Second soft body node.
dynamics::PointMass *	mPointMass1
	First point mass.
dynamics::PointMass *	mPointMass2
	Second point mass.
std::vector< collision::Contact * >	mContacts
	Contacts between mBodyNode1 and mBodyNode2.
collision::SoftCollisionInfo *	mSoftCollInfo
	Soft collision information.
Eigen::Vector3d	mFirstFrictionalDirection
	First frictional direction.
double	mFrictionCoeff
	Coefficient of Friction.
double	mRestitutionCoeff
	Coefficient of restitution.
common::aligned_vector< Eigen::Vector6d >	mJacobians1
	Local body jacobians for mBodyNode1.
common::aligned_vector< Eigen::Vector6d >	mJacobians2
	Local body jacobians for mBodyNode2.
Eigen::Vector3d	mBodyDirection1
	Contact normal expressed in body frame of the first body node.
Eigen::Vector3d	mBodyDirection2
	Contact normal expressed in body frame of the second body node.
bool	mIsFrictionOn
std::size_t	mAppliedImpulseIndex
	Index of applied impulse.
bool	mIsBounceOn
bool	mActive

Static Private 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-5
	Global constraint force mixing parameter in the range of [1e-9, 1].

Friends
class	ConstraintSolver
class	ConstrainedGroup

Detailed Description

SoftContactConstraint represents a contact constraint between two bodies.

Constructor & Destructor Documentation

SoftContactConstraint()

dart::constraint::SoftContactConstraint::SoftContactConstraint	(	collision::Contact &	_contact,
		double	_timeStep
	)

Constructor.

~SoftContactConstraint()

dart::constraint::SoftContactConstraint::~SoftContactConstraint ( )

virtual

Destructor.

Member Function Documentation

applyImpulse()

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

overrideprotectedvirtual

Apply computed constraint impulse to constrained skeletons.

Implements dart::constraint::ConstraintBase.

applyUnitImpulse()

void dart::constraint::SoftContactConstraint::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

computeFrictionCoefficient()

double dart::constraint::SoftContactConstraint::computeFrictionCoefficient ( const dynamics::ShapeNode *  shapeNode )

staticprotected

computeRestitutionCoefficient()

double dart::constraint::SoftContactConstraint::computeRestitutionCoefficient ( const dynamics::ShapeNode *  shapeNode )

staticprotected

excite()

void dart::constraint::SoftContactConstraint::excite ( )

overrideprotectedvirtual

Excite the constraint.

Implements dart::constraint::ConstraintBase.

getConstraintForceMixing()

double dart::constraint::SoftContactConstraint::getConstraintForceMixing ( )

static

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::SoftContactConstraint::getErrorAllowance ( )

static

Get global error reduction parameter.

getErrorReductionParameter()

double dart::constraint::SoftContactConstraint::getErrorReductionParameter ( )

static

Get global error reduction parameter.

getFrictionDirection1()

const Eigen::Vector3d & dart::constraint::SoftContactConstraint::getFrictionDirection1

(

)

const

Get first frictional direction.

getInformation()

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

overrideprotectedvirtual

Fill LCP variables.

Implements dart::constraint::ConstraintBase.

getMaxErrorReductionVelocity()

double dart::constraint::SoftContactConstraint::getMaxErrorReductionVelocity ( )

static

Get global error reduction parameter.

getRelVelocity()

void dart::constraint::SoftContactConstraint::getRelVelocity ( double *  _vel )

private

Get change in relative velocity at contact point due to external impulse.

Parameters

[out]

_vel

Change in relative velocity at contact point of the two colliding bodies

getRootSkeleton() [1/2]

dynamics::SkeletonPtr dart::constraint::SoftContactConstraint::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::SoftContactConstraint::getStaticType ( )

static

Returns constraint type for this class.

getTangentBasisMatrixODE()

Eigen::MatrixXd dart::constraint::SoftContactConstraint::getTangentBasisMatrixODE ( const Eigen::Vector3d &  _n )

private

getType()

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

overridevirtual

Returns a string representing the constraint type.

Reimplemented from dart::constraint::ConstraintBase.

getVelocityChange()

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

overrideprotectedvirtual

Get velocity change due to the uint impulse.

Implements dart::constraint::ConstraintBase.

isActive()

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

overrideprotectedvirtual

Return true if this constraint is active.

Implements dart::constraint::ConstraintBase.

selectCollidingPointMass() [1/2]

const dynamics::PointMass * dart::constraint::SoftContactConstraint::selectCollidingPointMass ( const dynamics::SoftBodyNode *  _softBodyNode, const Eigen::Vector3d &  _point, int  _faceId  ) const

private

Find the nearest point mass from _point in a face, of which id is _faceId in _softBodyNode.

Returns a pointer to a const, and is usable with a const SoftBodyNode.

selectCollidingPointMass() [2/2]

dynamics::PointMass * dart::constraint::SoftContactConstraint::selectCollidingPointMass ( dynamics::SoftBodyNode *  _softBodyNode, const Eigen::Vector3d &  _point, int  _faceId  ) const

private

Find the nearest point mass from _point in a face, of which id is _faceId in _softBodyNode.

setConstraintForceMixing()

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

static

Set global constraint force mixing parameter.

setErrorAllowance()

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

static

Set global error reduction parameter.

setErrorReductionParameter()

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

static

Set global error reduction parameter.

setFrictionDirection()

void dart::constraint::SoftContactConstraint::setFrictionDirection

(

const Eigen::Vector3d &

_dir

)

Set first frictional direction.

setMaxErrorReductionVelocity()

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

static

Set global error reduction parameter.

unexcite()

void dart::constraint::SoftContactConstraint::unexcite ( )

overrideprotectedvirtual

Unexcite the constraint.

Implements dart::constraint::ConstraintBase.

uniteSkeletons()

void dart::constraint::SoftContactConstraint::uniteSkeletons ( )

overrideprotectedvirtual

Reimplemented from dart::constraint::ConstraintBase.

update()

void dart::constraint::SoftContactConstraint::update ( )

overrideprotectedvirtual

Update constraint using updated Skeleton's states.

Implements dart::constraint::ConstraintBase.

updateFirstFrictionalDirection()

void dart::constraint::SoftContactConstraint::updateFirstFrictionalDirection ( )

private

Friends And Related Symbol Documentation

ConstrainedGroup

friend class ConstrainedGroup

friend

ConstraintSolver

friend class ConstraintSolver

friend

Member Data Documentation

mActive

bool dart::constraint::SoftContactConstraint::mActive

private

mAppliedImpulseIndex

std::size_t dart::constraint::SoftContactConstraint::mAppliedImpulseIndex

private

Index of applied impulse.

mBodyDirection1

Eigen::Vector3d dart::constraint::SoftContactConstraint::mBodyDirection1

private

Contact normal expressed in body frame of the first body node.

mBodyDirection2

Eigen::Vector3d dart::constraint::SoftContactConstraint::mBodyDirection2

private

Contact normal expressed in body frame of the second body node.

mBodyNode1

dynamics::BodyNode* dart::constraint::SoftContactConstraint::mBodyNode1

private

Fircst body node.

mBodyNode2

dynamics::BodyNode* dart::constraint::SoftContactConstraint::mBodyNode2

private

Second body node.

mConstraintForceMixing

double dart::constraint::SoftContactConstraint::mConstraintForceMixing = 1e-5

staticprivate

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

mContacts

std::vector<collision::Contact*> dart::constraint::SoftContactConstraint::mContacts

private

Contacts between mBodyNode1 and mBodyNode2.

mDim

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

protectedinherited

Dimension of constraint.

mErrorAllowance

double dart::constraint::SoftContactConstraint::mErrorAllowance = 0.0

staticprivate

Global constraint error allowance.

mErrorReductionParameter

double dart::constraint::SoftContactConstraint::mErrorReductionParameter = 0.01

staticprivate

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

The default is 0.01.

mFirstFrictionalDirection

Eigen::Vector3d dart::constraint::SoftContactConstraint::mFirstFrictionalDirection

private

First frictional direction.

mFrictionCoeff

double dart::constraint::SoftContactConstraint::mFrictionCoeff

private

Coefficient of Friction.

mIsBounceOn

bool dart::constraint::SoftContactConstraint::mIsBounceOn

private

mIsFrictionOn

bool dart::constraint::SoftContactConstraint::mIsFrictionOn

private

mJacobians1

common::aligned_vector<Eigen::Vector6d> dart::constraint::SoftContactConstraint::mJacobians1

private

Local body jacobians for mBodyNode1.

mJacobians2

common::aligned_vector<Eigen::Vector6d> dart::constraint::SoftContactConstraint::mJacobians2

private

Local body jacobians for mBodyNode2.

mMaxErrorReductionVelocity

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

staticprivate

Maximum error reduction velocity.

mPointMass1

dynamics::PointMass* dart::constraint::SoftContactConstraint::mPointMass1

private

First point mass.

mPointMass2

dynamics::PointMass* dart::constraint::SoftContactConstraint::mPointMass2

private

Second point mass.

mRestitutionCoeff

double dart::constraint::SoftContactConstraint::mRestitutionCoeff

private

Coefficient of restitution.

mSoftBodyNode1

dynamics::SoftBodyNode* dart::constraint::SoftContactConstraint::mSoftBodyNode1

private

First soft body node.

mSoftBodyNode2

dynamics::SoftBodyNode* dart::constraint::SoftContactConstraint::mSoftBodyNode2

private

Second soft body node.

mSoftCollInfo

collision::SoftCollisionInfo* dart::constraint::SoftContactConstraint::mSoftCollInfo

private

Soft collision information.

mTimeStep

double dart::constraint::SoftContactConstraint::mTimeStep

private

Time step.