KDL::Joint Class Reference

This class encapsulates a simple joint, that is with one parameterized degree of freedom and with scalar dynamic properties. More...

#include <src/joint.hpp>

Collaboration diagram for KDL::Joint:

[legend]

List of all members.

Classes
class	joint_type_exception
Public Types
enum	JointType {   RotAxis, RotX, RotY, RotZ,   TransAxis, TransX, TransY, TransZ,   None }
Public Member Functions
	Joint (const std::string &name, const JointType &type=None, const double &scale=1, const double &offset=0, const double &inertia=0, const double &damping=0, const double &stiffness=0)
	Constructor of a joint.
	Joint (const JointType &type=None, const double &scale=1, const double &offset=0, const double &inertia=0, const double &damping=0, const double &stiffness=0)
	Constructor of a joint.
	Joint (const std::string &name, const Vector &_origin, const Vector &_axis, const JointType &type, const double &_scale=1, const double &_offset=0, const double &_inertia=0, const double &_damping=0, const double &_stiffness=0)
	Constructor of a joint.
	Joint (const Vector &_origin, const Vector &_axis, const JointType &type, const double &_scale=1, const double &_offset=0, const double &_inertia=0, const double &_damping=0, const double &_stiffness=0)
	Constructor of a joint.
Frame	pose (const double &q) const
	Request the 6D-pose between the beginning and the end of the joint at joint position q.
Twist	twist (const double &qdot) const
	Request the resulting 6D-velocity with a joint velocity qdot.
Vector	JointAxis () const
	Request the Vector corresponding to the axis of a revolute joint.
Vector	JointOrigin () const
	Request the Vector corresponding to the origin of a revolute joint.
const std::string &	getName () const
	Request the name of the joint.
const JointType &	getType () const
	Request the type of the joint.
const std::string	getTypeName () const
	Request the stringified type of the joint.
virtual	~Joint ()
Private Attributes
std::string	name
Joint::JointType	type
double	scale
double	offset
double	inertia
double	damping
double	stiffness
Vector	axis
Vector	origin
Frame	joint_pose
double	q_previous
KDL::Joint::joint_type_exception	joint_type_ex

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Detailed Description

This class encapsulates a simple joint, that is with one parameterized degree of freedom and with scalar dynamic properties.

A simple joint is described by the following properties :

• scale: ratio between motion input and motion output
• offset: between the "physical" and the "logical" zero position.
• type: revolute or translational, along one of the basic frame axes
• inertia, stiffness and damping: scalars representing the physical effects along/about the joint axis only.

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Member Enumeration Documentation

enum KDL::Joint::JointType

Enumerator:

RotAxis
RotX
RotY
RotZ
TransAxis
TransX
TransY
TransZ
None

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Constructor & Destructor Documentation

KDL::Joint::Joint	(	const std::string &	name,
		const JointType &	type = None,
		const double &	scale = 1,
		const double &	offset = 0,
		const double &	inertia = 0,
		const double &	damping = 0,
		const double &	stiffness = 0
	)

Constructor of a joint.

Parameters:

	name	of the joint
	type	type of the joint, default: Joint::None
	scale	scale between joint input and actual geometric movement, default: 1
	offset	offset between joint input and actual geometric input, default: 0
	inertia	1D inertia along the joint axis, default: 0
	damping	1D damping along the joint axis, default: 0
	stiffness	1D stiffness along the joint axis, default: 0

References joint_type_ex, RotAxis, TransAxis, and type.

KDL::Joint::Joint	(	const JointType &	type = None,
		const double &	scale = 1,
		const double &	offset = 0,
		const double &	inertia = 0,
		const double &	damping = 0,
		const double &	stiffness = 0
	)

Constructor of a joint.

Parameters:

	type	type of the joint, default: Joint::None
	scale	scale between joint input and actual geometric movement, default: 1
	offset	offset between joint input and actual geometric input, default: 0
	inertia	1D inertia along the joint axis, default: 0
	damping	1D damping along the joint axis, default: 0
	stiffness	1D stiffness along the joint axis, default: 0

References joint_type_ex, RotAxis, TransAxis, and type.

KDL::Joint::Joint	(	const std::string &	name,
		const Vector &	_origin,
		const Vector &	_axis,
		const JointType &	type,
		const double &	_scale = 1,
		const double &	_offset = 0,
		const double &	_inertia = 0,
		const double &	_damping = 0,
		const double &	_stiffness = 0
	)

Constructor of a joint.

Parameters:

	name	of the joint
	origin	the origin of the joint
	axis	the axis of the joint
	scale	scale between joint input and actual geometric movement, default: 1
	offset	offset between joint input and actual geometric input, default: 0
	inertia	1D inertia along the joint axis, default: 0
	damping	1D damping along the joint axis, default: 0
	stiffness	1D stiffness along the joint axis, default: 0

References axis, joint_pose, joint_type_ex, KDL::Frame::M, offset, origin, KDL::Frame::p, q_previous, KDL::Rotation::Rot2(), RotAxis, TransAxis, and type.

KDL::Joint::Joint	(	const Vector &	_origin,
		const Vector &	_axis,
		const JointType &	type,
		const double &	_scale = 1,
		const double &	_offset = 0,
		const double &	_inertia = 0,
		const double &	_damping = 0,
		const double &	_stiffness = 0
	)

Constructor of a joint.

Parameters:

	origin	the origin of the joint
	axis	the axis of the joint
	scale	scale between joint input and actual geometric movement, default: 1
	offset	offset between joint input and actual geometric input, default: 0
	inertia	1D inertia along the joint axis, default: 0
	damping	1D damping along the joint axis, default: 0
	stiffness	1D stiffness along the joint axis, default: 0

References axis, joint_pose, joint_type_ex, KDL::Frame::M, offset, origin, KDL::Frame::p, q_previous, KDL::Rotation::Rot2(), RotAxis, TransAxis, and type.

KDL::Joint::~Joint

(

)

[virtual]

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Member Function Documentation

const std::string& KDL::Joint::getName

(

)

const [inline]

Request the name of the joint.

Returns:

const reference to the name of the joint

References name.

Referenced by KDL::Tree::getChain().

const JointType& KDL::Joint::getType

(

)

const [inline]

Request the type of the joint.

Returns:

const reference to the type

References type.

Referenced by KDL::Tree::addSegment(), KDL::Chain::addSegment(), KDL::ChainIdSolver_RNE::CartToJnt(), KDL::Tree::getChain(), and KDL::ChainJntToJacSolver::JntToJac().

const std::string KDL::Joint::getTypeName

(

)

const [inline]

Request the stringified type of the joint.

Returns:

const string

References None, RotAxis, RotX, RotY, RotZ, TransAxis, TransX, TransY, TransZ, and type.

Vector KDL::Joint::JointAxis

(

)

const

Request the Vector corresponding to the axis of a revolute joint.

Returns:

Vector. e.g (1,0,0) for RotX etc.

References axis, None, RotAxis, RotX, RotY, RotZ, TransAxis, TransX, TransY, TransZ, type, and KDL::Vector::Zero().

Referenced by KDL::Tree::getChain().

Vector KDL::Joint::JointOrigin

(

)

const

Request the Vector corresponding to the origin of a revolute joint.

Returns:

Vector

References origin.

Referenced by KDL::Tree::getChain().

Frame KDL::Joint::pose

(

const double &

q

)

const

Request the 6D-pose between the beginning and the end of the joint at joint position q.

Parameters:

q

the 1D joint position

Returns:

the resulting 6D-pose

References axis, KDL::Frame::Identity(), joint_pose, KDL::Frame::M, None, offset, origin, q_previous, KDL::Rotation::Rot2(), RotAxis, KDL::Rotation::RotX(), RotX, KDL::Rotation::RotY(), RotY, KDL::Rotation::RotZ(), RotZ, scale, TransAxis, TransX, TransY, TransZ, and type.

Referenced by KDL::Segment::getFrameToTip(), KDL::Segment::pose(), and KDL::Segment::twist().

Twist KDL::Joint::twist

(

const double &

qdot

)

const

Request the resulting 6D-velocity with a joint velocity qdot.

Parameters:

qdot

the 1D joint velocity

Returns:

the resulting 6D-velocity

References axis, None, RotAxis, RotX, RotY, RotZ, scale, TransAxis, TransX, TransY, TransZ, type, and KDL::Twist::Zero().

Referenced by KDL::Segment::twist().

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Member Data Documentation

Vector KDL::Joint::axis [private]

Referenced by Joint(), JointAxis(), pose(), and twist().

double KDL::Joint::damping [private]

double KDL::Joint::inertia [private]

Frame KDL::Joint::joint_pose [mutable, private]

Referenced by Joint(), and pose().

KDL::Joint::joint_type_exception KDL::Joint::joint_type_ex [private]

Referenced by Joint().

std::string KDL::Joint::name [private]

Referenced by getName().

double KDL::Joint::offset [private]

Referenced by Joint(), and pose().

Vector KDL::Joint::origin [private]

Referenced by Joint(), JointOrigin(), and pose().

double KDL::Joint::q_previous [mutable, private]

Referenced by Joint(), and pose().

double KDL::Joint::scale [private]

Referenced by pose(), and twist().

double KDL::Joint::stiffness [private]

Joint::JointType KDL::Joint::type [private]

Referenced by getType(), getTypeName(), Joint(), JointAxis(), pose(), and twist().

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

• src/joint.hpp
• src/joint.cpp