hpp::pinocchio::Joint Class Reference

#include <hpp/pinocchio/joint.hh>

Public Member Functions
DeviceConstPtr_t	robot () const
	Access robot owning the object.
DevicePtr_t	robot ()
	Access robot owning the object.
std::ostream &	display (std::ostream &os) const
	Display joint.
LiegroupSpacePtr_t	configurationSpace () const
	Get configuration space of joint.
LiegroupSpacePtr_t	RnxSOnConfigurationSpace () const
bool	operator== (const Joint &other) const
bool	operator!= (const Joint &other) const
Name
const std::string &	name () const
	Get name.
Position
const Transform3s &	currentTransformation () const
	Joint transformation.
const Transform3s &	currentTransformation (const DeviceData &data) const
	Joint transformation.
Size and rank
size_type	numberDof () const
	Return number of degrees of freedom.
size_type	configSize () const
	Return number of degrees of freedom.
size_type	rankInConfiguration () const
	Return rank of the joint in the configuration vector.
size_type	rankInVelocity () const
	Return rank of the joint in the velocity vector.
Kinematic chain
JointPtr_t	parentJoint () const
	Get a pointer to the parent joint (if any).
std::size_t	numberChildJoints () const
	Number of child joints.
JointPtr_t	childJoint (std::size_t rank) const
	Get child joint.
const Transform3s &	positionInParentFrame () const
Bounds
void	isBounded (size_type rank, bool bounded)
bool	isBounded (size_type rank) const
	Get whether given degree of freedom is bounded.
value_type	lowerBound (size_type rank) const
	Get lower bound of given degree of freedom.
value_type	upperBound (size_type rank) const
	Get upper bound of given degree of freedom.
void	lowerBound (size_type rank, value_type lowerBound)
	Set lower bound of given degree of freedom.
void	upperBound (size_type rank, value_type upperBound)
	Set upper bound of given degree of freedom.
void	lowerBounds (vectorIn_t lowerBounds)
	Set lower bounds.
void	upperBounds (vectorIn_t upperBounds)
	Set upper bounds.
value_type	upperBoundLinearVelocity () const
value_type	upperBoundAngularVelocity () const
const value_type &	maximalDistanceToParent ()
	Maximal distance of joint origin to parent origin.
Jacobian
JointJacobian_t &	jacobian (const bool localFrame=true) const
JointJacobian_t &	jacobian (DeviceData &data, const bool localFrame=true) const
Body linked to the joint
BodyPtr_t	linkedBody () const
	Get linked body.

Protected Member Functions
void	computeMaximalDistanceToParent ()
	Compute the maximal distance.
void	setChildList ()
	Store list of childrens.
Model &	model ()
const Model &	model () const
DeviceData &	data () const
void	selfAssert () const
	Assert that the members of the struct are valid (no null pointer, etc).
	Joint ()
	HPP_SERIALIZABLE ()

Protected Attributes
value_type	maximalDistanceToParent_
DeviceWkPtr_t	devicePtr
JointIndex	jointIndex
std::vector< JointIndex >	children

Friends
class	Device

Construction and copy and destruction
static JointPtr_t	create (DeviceWkPtr_t device, JointIndex indexInJointList)
	Joint (DeviceWkPtr_t device, JointIndex indexInJointList)
	~Joint ()

Pinocchio API
static size_type	index (const JointConstPtr_t &joint)
const JointIndex &	index () const
const JointModel &	jointModel () const

Detailed Description

Robot joint

A joint maps an input vector to a transformation of SE(3) from the parent frame to the joint frame.

The input vector is provided through the configuration vector of the robot the joint belongs to. The joint input vector is composed of the components of the robot configuration starting at Joint::rankInConfiguration.

The joint input vector represents an element of a Lie group, either

• a vector space for JointTranslation, and bounded JointRotation,
• the unit circle for non-bounded JointRotation joints,
• an element of SO(3) for JointSO3, represented by a unit quaternion.

This class is a wrapper to pinocchio::JointModelTpl.

Constructor & Destructor Documentation

Joint() [1/2]

hpp::pinocchio::Joint::Joint	(	DeviceWkPtr_t	device,
		JointIndex	indexInJointList )

Constructor

Parameters

indexInJointList

index in pinocchio vector of joints (pinocchio::ModelTpl::joints). Should be > 0.

Note

indices of device start at 1 since 0 corresponds to "universe".

~Joint()

hpp::pinocchio::Joint::~Joint ( )

inline

Joint() [2/2]

hpp::pinocchio::Joint::Joint ( )

inlineprotected

Member Function Documentation

childJoint()

JointPtr_t hpp::pinocchio::Joint::childJoint

(

std::size_t

rank

)

const

Get child joint.

computeMaximalDistanceToParent()

void hpp::pinocchio::Joint::computeMaximalDistanceToParent ( )

protected

Compute the maximal distance.

See also

maximalDistanceToParent

configSize()

size_type hpp::pinocchio::Joint::configSize

(

)

const

Return number of degrees of freedom.

configurationSpace()

LiegroupSpacePtr_t hpp::pinocchio::Joint::configurationSpace

(

)

const

Get configuration space of joint.

create()

JointPtr_t hpp::pinocchio::Joint::create ( DeviceWkPtr_t device, JointIndex indexInJointList )

static

Create a new joint

Parameters

indexInJointList

index in pinocchio vector of joints (pinocchio::ModelTpl::joints)

Returns

shared pointer to result if indexInJointList > 0, empty shared pointer if indexInJointList == 0.

Note

indices of device start at 1 since 0 corresponds to "universe".

currentTransformation() [1/2]

const Transform3s & hpp::pinocchio::Joint::currentTransformation ( ) const

inline

Joint transformation.

currentTransformation() [2/2]

const Transform3s & hpp::pinocchio::Joint::currentTransformation

(

const DeviceData &

data

)

const

Joint transformation.

data()

DeviceData & hpp::pinocchio::Joint::data ( ) const

protected

display()

std::ostream & hpp::pinocchio::Joint::display

(

std::ostream &

os

)

const

Display joint.

HPP_SERIALIZABLE()

hpp::pinocchio::Joint::HPP_SERIALIZABLE ( )

protected

index() [1/2]

const JointIndex & hpp::pinocchio::Joint::index ( ) const

inline

index() [2/2]

size_type hpp::pinocchio::Joint::index ( const JointConstPtr_t & joint )

inlinestatic

Get the index for a given joint

Returns

0 if joint is NULL ("universe"), joint->index() otherwise.

isBounded() [1/2]

bool hpp::pinocchio::Joint::isBounded

(

size_type

rank

)

const

Get whether given degree of freedom is bounded.

isBounded() [2/2]

void hpp::pinocchio::Joint::isBounded	(	size_type	rank,
		bool	bounded )

Set whether given degree of freedom is bounded

Warning

Joint always has bounds. When bounded == false, the bounds are -infinity and infinity.

jacobian() [1/2]

JointJacobian_t & hpp::pinocchio::Joint::jacobian ( const bool localFrame = true ) const

inline

Get non const reference to Jacobian

Parameters

localFrame

if true, compute the jacobian (6d) in the local frame, whose linear part corresponds to the velocity of the center of the frame. If false, the jacobian is expressed in the global frame and its linear part corresponds to the value of the velocity vector field at the center of the world.

jacobian() [2/2]

JointJacobian_t & hpp::pinocchio::Joint::jacobian	(	DeviceData &	data,
		const bool	localFrame = true ) const

Get reference to Jacobian

Parameters

data	a DeviceData (see hpp::pinocchio::DeviceSync for details).
localFrame	if true, compute the jacobian (6d) in the local frame, whose linear part corresponds to the velocity of the center of the frame. If false, the jacobian is expressed in the global frame and its linear part corresponds to the value of the velocity vector field at the center of the world.

jointModel()

const JointModel & hpp::pinocchio::Joint::jointModel

(

)

const

linkedBody()

BodyPtr_t hpp::pinocchio::Joint::linkedBody

(

)

const

Get linked body.

lowerBound() [1/2]

value_type hpp::pinocchio::Joint::lowerBound

(

size_type

rank

)

const

Get lower bound of given degree of freedom.

lowerBound() [2/2]

void hpp::pinocchio::Joint::lowerBound	(	size_type	rank,
		value_type	lowerBound )

Set lower bound of given degree of freedom.

lowerBounds()

void hpp::pinocchio::Joint::lowerBounds

(

vectorIn_t

lowerBounds

)

Set lower bounds.

maximalDistanceToParent()

const value_type & hpp::pinocchio::Joint::maximalDistanceToParent ( )

inline

Maximal distance of joint origin to parent origin.

model() [1/2]

Model & hpp::pinocchio::Joint::model ( )

protected

model() [2/2]

const Model & hpp::pinocchio::Joint::model ( ) const

protected

name()

const std::string & hpp::pinocchio::Joint::name

(

)

const

Get name.

numberChildJoints()

std::size_t hpp::pinocchio::Joint::numberChildJoints

(

)

const

Number of child joints.

numberDof()

size_type hpp::pinocchio::Joint::numberDof

(

)

const

Return number of degrees of freedom.

operator!=()

bool hpp::pinocchio::Joint::operator!= ( const Joint & other ) const

inline

operator==()

bool hpp::pinocchio::Joint::operator== ( const Joint & other ) const

inline

parentJoint()

JointPtr_t hpp::pinocchio::Joint::parentJoint

(

)

const

Get a pointer to the parent joint (if any).

positionInParentFrame()

const Transform3s & hpp::pinocchio::Joint::positionInParentFrame

(

)

const

Get (constant) placement of joint in parent frame, i.e. model.jointPlacement[idx]

rankInConfiguration()

size_type hpp::pinocchio::Joint::rankInConfiguration

(

)

const

Return rank of the joint in the configuration vector.

rankInVelocity()

size_type hpp::pinocchio::Joint::rankInVelocity

(

)

const

Return rank of the joint in the velocity vector.

RnxSOnConfigurationSpace()

LiegroupSpacePtr_t hpp::pinocchio::Joint::RnxSOnConfigurationSpace

(

)

const

Get configuration space of joint. Use R^n x SO(n) instead of SE(n).

robot() [1/2]

DevicePtr_t hpp::pinocchio::Joint::robot ( )

inline

Access robot owning the object.

robot() [2/2]

DeviceConstPtr_t hpp::pinocchio::Joint::robot ( ) const

inline

Access robot owning the object.

selfAssert()

void hpp::pinocchio::Joint::selfAssert ( ) const

protected

Assert that the members of the struct are valid (no null pointer, etc).

setChildList()

void hpp::pinocchio::Joint::setChildList ( )

protected

Store list of childrens.

upperBound() [1/2]

value_type hpp::pinocchio::Joint::upperBound

(

size_type

rank

)

const

Get upper bound of given degree of freedom.

upperBound() [2/2]

void hpp::pinocchio::Joint::upperBound	(	size_type	rank,
		value_type	upperBound )

Set upper bound of given degree of freedom.

upperBoundAngularVelocity()

value_type hpp::pinocchio::Joint::upperBoundAngularVelocity

(

)

const

Get upper bound on angular velocity of the joint frame

Returns

coefficient \(\lambda\) such that

\begin{equation*}\forall \mathbf{q}_{joint}\ \ \ \ \ \ \|\omega\| \leq \lambda \|\mathbf{\dot{q}}_{joint}\| \end{equation*}

where

• \(\mathbf{q}_{joint}\) is any joint configuration,
• \(\mathbf{\dot{q}}_{joint}\) is the joint velocity, and
• \(\omega = J(\mathbf{q})*\mathbf{\dot{q}}\) is the angular velocity of the joint frame.

upperBoundLinearVelocity()

value_type hpp::pinocchio::Joint::upperBoundLinearVelocity

(

)

const

Get upper bound on linear velocity of the joint frame

Returns

coefficient \(\lambda\) such that

\begin{equation*}\forall \mathbf{q}_{joint}\ \ \ \ \ \ \|\mathbf {v}\| \leq \lambda \|\mathbf{\dot{q}}_{joint}\| \end{equation*}

where

• \(\mathbf{q}_{joint}\) is any joint configuration,
• \(\mathbf{\dot{q}}_{joint}\) is the joint velocity, and
• \(\mathbf{v} = J(\mathbf{q})*\mathbf{\dot{q}} \) is the linear velocity of the joint frame.

upperBounds()

void hpp::pinocchio::Joint::upperBounds

(

vectorIn_t

upperBounds

)

Set upper bounds.

Friends And Related Symbol Documentation

Device

friend class Device

friend

Member Data Documentation

children

std::vector<JointIndex> hpp::pinocchio::Joint::children

protected

devicePtr

DeviceWkPtr_t hpp::pinocchio::Joint::devicePtr

protected

jointIndex

JointIndex hpp::pinocchio::Joint::jointIndex

protected

maximalDistanceToParent_

value_type hpp::pinocchio::Joint::maximalDistanceToParent_

protected

---

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

• include/hpp/pinocchio/joint.hh