Computes the Jacobian time derivative (Jdot) by calculating the partial derivatives regarding to a joint angle, in the Hybrid, Body-fixed or Inertial representation. More...

#include <chainjnttojacdotsolver.hpp>

Inheritance diagram for KDL::ChainJntToJacDotSolver:

[legend]

List of all members.

Public Member Functions
	ChainJntToJacDotSolver (const Chain &chain)
virtual int	JntToJacDot (const KDL::JntArrayVel &q_in, KDL::Twist &jac_dot_q_dot, int seg_nr=-1)
	Computes ${}_{bs}\dot{J}^{ee}.\dot{q}$ .
virtual int	JntToJacDot (const KDL::JntArrayVel &q_in, KDL::Jacobian &jdot, int seg_nr=-1)
	Computes ${}_{bs}\dot{J}^{ee}$ .
void	setBodyFixedRepresentation ()
	JntToJacDot() will compute in the Body-fixed representation (ref Frame: end-effector, ref Point: end-effector)
void	setHybridRepresentation ()
	JntToJacDot() will compute in the Hybrid representation (ref Frame: base, ref Point: end-effector)
void	setInertialRepresentation ()
	JntToJacDot() will compute in the Inertial representation (ref Frame: base, ref Point: base)
int	setLockedJoints (const std::vector< bool > &locked_joints)
void	setRepresentation (const int &representation)
	Sets the internal variable for the representation (with a check on the value)
virtual const char *	strError (const int error) const
virtual void	updateInternalDataStructures ()
virtual	~ChainJntToJacDotSolver ()
Static Public Attributes
static const int	BODYFIXED = 1
static const int	E_FKSOLVERPOS_FAILED = -102
static const int	E_JAC_DOT_FAILED = -100
static const int	E_JACSOLVER_FAILED = -101
static const int	HYBRID = 0
static const int	INERTIAL = 2
Protected Member Functions
const Twist &	getPartialDerivative (const Jacobian &J, const unsigned int &joint_idx, const unsigned int &column_idx, const int &representation)
	Computes $\frac{\partial J^{i,ee}}{\partial q^{j}}.\dot{q}^{j}$ .
const Twist &	getPartialDerivativeBodyFixed (const Jacobian &ee_J_ee, const unsigned int &joint_idx, const unsigned int &column_idx)
	Computes $\frac{\partial {}_{ee}J^{i,ee}}{\partial q^{j}}.\dot{q}^{j}$ .
const Twist &	getPartialDerivativeHybrid (const Jacobian &bs_J_ee, const unsigned int &joint_idx, const unsigned int &column_idx)
	Computes $\frac{\partial {}_{bs}J^{i,ee}}{\partial q^{j}}.\dot{q}^{j}$ .
const Twist &	getPartialDerivativeInertial (const Jacobian &bs_J_bs, const unsigned int &joint_idx, const unsigned int &column_idx)
	Computes $\frac{\partial {}_{bs}J^{i,bs}}{\partial q^{j}}.\dot{q}^{j}$ .
Private Attributes
const Chain &	chain
Frame	F_bs_ee_
ChainFkSolverPos_recursive	fk_solver_
Jacobian	jac_
Jacobian	jac_dot_
Twist	jac_dot_k_
Twist	jac_i_
Twist	jac_j_
ChainJntToJacSolver	jac_solver_
std::vector< bool >	locked_joints_
unsigned int	nr_of_unlocked_joints_
int	representation_
Twist	t_djdq_

Detailed Description

Computes the Jacobian time derivative (Jdot) by calculating the partial derivatives regarding to a joint angle, in the Hybrid, Body-fixed or Inertial representation.

This work is based on : Symbolic differentiation of the velocity mapping for a serial kinematic chain H. Bruyninckx, J. De Schutter doi:10.1016/0094-114X(95)00069-B

url : http://www.sciencedirect.com/science/article/pii/0094114X9500069B

Definition at line 48 of file chainjnttojacdotsolver.hpp.

Constructor & Destructor Documentation

KDL::ChainJntToJacDotSolver::ChainJntToJacDotSolver ( const Chain & chain ) [explicit]

Definition at line 26 of file chainjnttojacdotsolver.cpp.

KDL::ChainJntToJacDotSolver::~ChainJntToJacDotSolver ( ) [virtual]

Definition at line 241 of file chainjnttojacdotsolver.cpp.

Member Function Documentation

const Twist & KDL::ChainJntToJacDotSolver::getPartialDerivative	(	const Jacobian &	J,
		const unsigned int &	joint_idx,
		const unsigned int &	column_idx,
		const int &	representation
	)		`[protected]`

Computes $\frac{\partial J^{i,ee}}{\partial q^{j}}.\dot{q}^{j}$ .

Parameters:

bs_J_bs	The Jacobian expressed in the base frame with the end effector as the reference point
joint_idx	The indice of the current joint (j in the formula)
column_idx	The indice of the current column (i in the formula)
representation	The representation (Hybrid,Body-fixed,Inertial) in which you want to get dJ/dqj .qdotj

Returns:: Twist The twist representing dJi/dqj .qdotj

Definition at line 117 of file chainjnttojacdotsolver.cpp.

const Twist & KDL::ChainJntToJacDotSolver::getPartialDerivativeBodyFixed	(	const Jacobian &	ee_J_ee,
		const unsigned int &	joint_idx,
		const unsigned int &	column_idx
	)		`[protected]`

Computes $\frac{\partial {}_{ee}J^{i,ee}}{\partial q^{j}}.\dot{q}^{j}$ .

Parameters:

bs_J_ee	The Jacobian expressed in the end effector frame with the end effector as the reference point
joint_idx	The indice of the current joint (j in the formula)
column_idx	The indice of the current column (i in the formula)

Returns:: Twist The twist representing dJi/dqj .qdotj

Definition at line 167 of file chainjnttojacdotsolver.cpp.

const Twist & KDL::ChainJntToJacDotSolver::getPartialDerivativeHybrid	(	const Jacobian &	bs_J_ee,
		const unsigned int &	joint_idx,
		const unsigned int &	column_idx
	)		`[protected]`

Computes $\frac{\partial {}_{bs}J^{i,ee}}{\partial q^{j}}.\dot{q}^{j}$ .

Parameters:

bs_J_ee	The Jacobian expressed in the base frame with the end effector as the reference point (default in KDL Jacobian Solver)
joint_idx	The index of the current joint (j in the formula)
column_idx	The index of the current column (i in the formula)

Returns:: Twist The twist representing dJi/dqj .qdotj

Definition at line 136 of file chainjnttojacdotsolver.cpp.

const Twist & KDL::ChainJntToJacDotSolver::getPartialDerivativeInertial	(	const Jacobian &	bs_J_bs,
		const unsigned int &	joint_idx,
		const unsigned int &	column_idx
	)		`[protected]`

Computes $\frac{\partial {}_{bs}J^{i,bs}}{\partial q^{j}}.\dot{q}^{j}$ .

Parameters:

ee_J_ee	The Jacobian expressed in the base frame with the base as the reference point
joint_idx	The indice of the current joint (j in the formula)
column_idx	The indice of the current column (i in the formula)

Returns:: Twist The twist representing dJi/dqj .qdotj

Definition at line 189 of file chainjnttojacdotsolver.cpp.

int KDL::ChainJntToJacDotSolver::JntToJacDot	(	const KDL::JntArrayVel &	q_in,
		KDL::Twist &	jac_dot_q_dot,
		int	seg_nr = `-1`
	)		`[virtual]`

Computes ${}_{bs}\dot{J}^{ee}.\dot{q}$ .

Parameters:

q_in	Current joint positions and velocities
jac_dot_q_dot	The twist representing Jdot*qdot
seg_nr	The final segment to compute

Returns:: int 0 if no errors happened

Definition at line 47 of file chainjnttojacdotsolver.cpp.

int KDL::ChainJntToJacDotSolver::JntToJacDot	(	const KDL::JntArrayVel &	q_in,
		KDL::Jacobian &	jdot,
		int	seg_nr = `-1`
	)		`[virtual]`

Computes ${}_{bs}\dot{J}^{ee}$ .

Parameters:

q_in	Current joint positions and velocities
jdot	The jacobian time derivative in the configured representation (HYBRID, BODYFIXED or INERTIAL)
seg_nr	The final segment to compute

Returns:: int 0 if no errors happened

Definition at line 57 of file chainjnttojacdotsolver.cpp.

void KDL::ChainJntToJacDotSolver::setBodyFixedRepresentation ( ) [inline]

JntToJacDot() will compute in the Body-fixed representation (ref Frame: end-effector, ref Point: end-effector)

Returns:: void

Definition at line 97 of file chainjnttojacdotsolver.hpp.

void KDL::ChainJntToJacDotSolver::setHybridRepresentation ( ) [inline]

JntToJacDot() will compute in the Hybrid representation (ref Frame: base, ref Point: end-effector)

Returns:: void

Definition at line 91 of file chainjnttojacdotsolver.hpp.

void KDL::ChainJntToJacDotSolver::setInertialRepresentation ( ) [inline]

JntToJacDot() will compute in the Inertial representation (ref Frame: base, ref Point: base)

Returns:: void

Definition at line 103 of file chainjnttojacdotsolver.hpp.

int KDL::ChainJntToJacDotSolver::setLockedJoints ( const std::vector< bool > & locked_joints )

Definition at line 219 of file chainjnttojacdotsolver.cpp.

void KDL::ChainJntToJacDotSolver::setRepresentation ( const int & representation )

Sets the internal variable for the representation (with a check on the value)

Parameters:

representation The representation for Jdot : HYBRID,BODYFIXED or INERTIAL

Returns:: void

Definition at line 210 of file chainjnttojacdotsolver.cpp.

const char * KDL::ChainJntToJacDotSolver::strError ( const int error ) const [virtual]

Return a description of the latest error

Returns:: if error is known then a description of error, otherwise "UNKNOWN ERROR"

Reimplemented from KDL::SolverI.

Definition at line 233 of file chainjnttojacdotsolver.cpp.

void KDL::ChainJntToJacDotSolver::updateInternalDataStructures ( ) [virtual]

Update the internal data structures. This is required if the number of segments or number of joints of a chain/tree have changed. This provides a single point of contact for solver memory allocations.

Implements KDL::SolverI.

Definition at line 38 of file chainjnttojacdotsolver.cpp.