A class derived from iKinCtrl implementing the Levenberg-Marquardt algorithm: More...

#include <iKinInv.h>

Inheritance diagram for iCub::iKin::LMCtrl:

Public Member Functions
	LMCtrl (iKinChain &c, unsigned int _ctrlPose, double _Ts, double _mu0, double _mu_inc, double _mu_dec, double _mu_min, double _mu_max, double _sv_thres=1e-6)
	Constructor.

virtual yarp::sig::Vector	computeGPM ()
	Returns the further contribution to the qdot=pinvJ*xdot equation according to the Gradient Projection Method, i.e.

virtual void	setChainConstraints (bool _constrained)
	Enables/Disables joint angles constraints.

virtual yarp::sig::Vector	iterate (yarp::sig::Vector &xd, const unsigned int verbose=0)
	Executes one iteration of the control algorithm.

virtual void	restart (const yarp::sig::Vector &q0)
	Reinitializes the algorithm's internal state and resets the starting point.

virtual bool	test_convergence (const double tol_size)
	Tests convergence by comparing the size of the algorithm internal structure (may be the gradient norm or the simplex size or whatever) to a certain tolerance.

virtual std::string	getAlgoName ()
	Returns the algorithm's name.

void	resetInt ()
	Resets integral status at the current joint angles.

yarp::sig::Vector	get_qdot () const
	Returns the actual derivative of joint angles.

yarp::sig::Vector	get_gpm () const
	Returns the actual value of Gradient Projected.

double	get_mu () const
	Returns the current weighting factor mu.

void	reset_mu ()
	Sets the weighting factor mu equal to the initial value.

virtual	~LMCtrl ()
	Destructor.

Public Member Functions inherited from iCub::iKin::iKinCtrl
	iKinCtrl (iKinChain &c, unsigned int _ctrlPose)
	Constructor.

virtual yarp::sig::Vector	solve (yarp::sig::Vector &xd, const double tol_size=IKINCTRL_DISABLED, const int max_iter=IKINCTRL_DISABLED, const unsigned int verbose=0, int exit_code=NULL, bool exhalt=NULL)
	Iterates the control algorithm trying to converge on the target.

void	switchWatchDog (bool sw)
	Switch on/off the watchDog mechanism to trigger deadLocks.

virtual void	setInTargetTol (double tol_x)
	Sets tolerance for in-target check (5e-3 by default).

virtual double	getInTargetTol () const
	Returns tolerance for in-target check.

virtual void	setWatchDogTol (double tol_q)
	Sets tolerance for watchDog check (1e-4 by default).

virtual double	getWatchDogTol () const
	Returns tolerance for watchDog check.

virtual void	setWatchDogMaxIter (int maxIter)
	Sets maximum number of iterations to trigger the watchDog (200 by default).

virtual int	getWatchDogMaxIter () const
	Returns maximum number of iterations to trigger the watchDog.

virtual bool	isInTarget ()
	Checks if the End-Effector is in target.

int	get_state () const
	Returns the algorithm's state.

void	set_ctrlPose (unsigned int _ctrlPose)
	Sets the state of Pose control settings.

unsigned int	get_ctrlPose () const
	Returns the state of Pose control settings.

unsigned int	get_dim () const
	Returns the number of Chain DOF.

unsigned int	get_iter () const
	Returns the number of performed iterations.

virtual yarp::sig::Vector	get_x () const
	Returns the actual cartesian position of the End-Effector.

virtual yarp::sig::Vector	get_e () const
	Returns the actual cartesian position error.

virtual void	set_q (const yarp::sig::Vector &q0)
	Sets the joint angles values.

virtual yarp::sig::Vector	get_q () const
	Returns the actual joint angles values.

virtual yarp::sig::Vector	get_grad () const
	Returns the actual gradient.

virtual yarp::sig::Matrix	get_J () const
	Returns the actual Jacobian used in computation.

virtual double	dist () const
	Returns the actual distance from the target in cartesian space (euclidean norm is used).

virtual	~iKinCtrl ()
	Default destructor.

Protected Member Functions
virtual double	update_mu ()

virtual void	inTargetFcn ()
	Method called whenever in target.

virtual void	deadLockRecoveryFcn ()
	Method called whenever the watchDog is triggered.

virtual void	printIter (const unsigned int verbose)
	Dumps warning or status messages.

virtual yarp::sig::Matrix	pinv (const yarp::sig::Matrix &A, const double tol=0.0)

Protected Member Functions inherited from iCub::iKin::iKinCtrl
virtual yarp::sig::Vector	calc_e ()
	Computes the error according to the current controller settings (complete pose/translational/rotational part).

virtual void	update_state ()
	Updates the control state.

virtual void	watchDog ()
	Handles the watchDog.

virtual yarp::sig::Vector	checkVelocity (const yarp::sig::Vector &_qdot, double _Ts)
	Checks each joint velocity and sets it to zero if it steers the joint out of range.

unsigned int	printHandling (const unsigned int verbose=0)
	Method to be called within the printIter routine inherited by children in order to handle the highest word of verbose integer.

Protected Attributes
double	Ts

ctrl::Integrator *	I

bool	constrained

yarp::sig::Vector	qdot

yarp::sig::Vector	gpm

yarp::sig::Matrix	pinvLM

double	mu

double	mu0

double	mu_inc

double	mu_dec

double	mu_min

double	mu_max

double	dist_old

double	svMin

double	svThres

Protected Attributes inherited from iCub::iKin::iKinCtrl
iKinChain &	chain

unsigned int	ctrlPose

yarp::sig::Vector	x_set

yarp::sig::Vector	x

yarp::sig::Vector	e

yarp::sig::Vector	q

yarp::sig::Matrix	J

yarp::sig::Matrix	Jt

yarp::sig::Matrix	pinvJ

yarp::sig::Vector	grad

yarp::sig::Vector	q_old

double	inTargetTol

double	watchDogTol

unsigned int	dim

unsigned int	iter

int	state

bool	watchDogOn

int	watchDogCnt

int	watchDogMaxIter

Detailed Description

A class derived from iKinCtrl implementing the Levenberg-Marquardt algorithm:

qdot=-pinv(Jt*J+mu*I)*grad

r(k)=dist(k)/dist(k-1) r(k)<1 => mu(k)=mu(k-1)*mu_dec; r(k)>1 => mu(k)=mu(k-1)*mu_inc;

H=Jt*J is the approximation of Hessian matrix

Definition at line 576 of file iKinInv.h.

Constructor & Destructor Documentation

◆ LMCtrl()

LMCtrl::LMCtrl	(	iKinChain &	c,
		unsigned int	_ctrlPose,
		double	_Ts,
		double	_mu0,
		double	_mu_inc,
		double	_mu_dec,
		double	_mu_min,
		double	_mu_max,
		double	_sv_thres = `1e-6`
	)

Constructor.

Parameters

c	is the Chain object on which the control operates. Do not change Chain DOF from this point onwards!!
_ctrlPose	one of the following: IKINCTRL_POSE_FULL => complete pose control. IKINCTRL_POSE_XYZ => translational part of pose controlled. IKINCTRL_POSE_ANG => rotational part of pose controlled.
_Ts	is the controller sample time.
_mu0	is the initial value for weighting factor mu.
_mu_inc	is the increasing factor.
_mu_dec	is the drecreasing factor.
_mu_min	is the minimum value for mu.
_mu_max	is the maximum value for mu.
_sv_thres	is the minimum singular value under which the mu is constantly kept equal to _mu_max.

Definition at line 466 of file iKinInv.cpp.

◆ ~LMCtrl()

LMCtrl::~LMCtrl ( )

virtual

Destructor.

Definition at line 669 of file iKinInv.cpp.

Member Function Documentation

◆ computeGPM()

virtual yarp::sig::Vector iCub::iKin::LMCtrl::computeGPM ( )

inlinevirtual

Returns the further contribution to the qdot=pinvJ*xdot equation according to the Gradient Projection Method, i.e.

qdot=pinvJ*xdot+(I-pinvJ*J)*w

Returns: shall return the quantity (I-pinvJ*J)*w.

Note: This method shall be inherited and handled accordingly (here a vector of 0s is returned). To do that, J and pinvJ are already computed when this method is called. The LM-inverse matrix pinvLM is also available.

Reimplemented in iCub::iKin::LMCtrl_GPM.

Definition at line 645 of file iKinInv.h.

◆ deadLockRecoveryFcn()

virtual void iCub::iKin::LMCtrl::deadLockRecoveryFcn ( )

inlineprotectedvirtual

Method called whenever the watchDog is triggered.

Put here the code to recover from deadLock. Shall be implemented.

Implements iCub::iKin::iKinCtrl.

Definition at line 609 of file iKinInv.h.

◆ get_gpm()

yarp::sig::Vector iCub::iKin::LMCtrl::get_gpm ( ) const

inline

Returns the actual value of Gradient Projected.

Returns: the actual value of Gradient Projected.

Definition at line 668 of file iKinInv.h.

◆ get_mu()

double iCub::iKin::LMCtrl::get_mu ( ) const

inline

Returns the current weighting factor mu.

Returns: the current weighting factor mu.

Definition at line 674 of file iKinInv.h.

◆ get_qdot()

yarp::sig::Vector iCub::iKin::LMCtrl::get_qdot ( ) const

inline

Returns the actual derivative of joint angles.

Returns: the actual derivative of joint angles.

Definition at line 662 of file iKinInv.h.

◆ getAlgoName()

virtual std::string iCub::iKin::LMCtrl::getAlgoName ( )

inlinevirtual

Returns the algorithm's name.

Returns: algorithm name as string. Shall be implemented.

Implements iCub::iKin::iKinCtrl.

Definition at line 651 of file iKinInv.h.

◆ inTargetFcn()

virtual void iCub::iKin::LMCtrl::inTargetFcn ( )

inlineprotectedvirtual

Method called whenever in target.

Shall be implemented.

Implements iCub::iKin::iKinCtrl.

Definition at line 608 of file iKinInv.h.

◆ iterate()

Vector LMCtrl::iterate	(	yarp::sig::Vector &	xd,
		const unsigned int	verbose = `0`
	)

virtual

Executes one iteration of the control algorithm.

Parameters

xd is the End-Effector target Pose to be tracked.

verbose is a integer whose 32 bits are intended as follows. The lowest word (16 bits) progressively enables different levels of warning messages or status dump: the larger this value the more detailed is the output (0x####0000=>off by default). The highest word indicates how many successive calls to the dump shall be skipped in order to reduce the amount of information on the screen (ex: 0x0000####=>print all iterations, 0x0001####=>print one iteration and skip the next one, 0x0002####=> print one iteration and skip the next two).

Returns: current estimation of joints configuration. Shall be implemented.

Implements iCub::iKin::iKinCtrl.

Definition at line 570 of file iKinInv.cpp.

◆ pinv()

Matrix LMCtrl::pinv	(	const yarp::sig::Matrix &	A,
		const double	tol = `0.0`
	)

protectedvirtual

Definition at line 507 of file iKinInv.cpp.

◆ printIter()

void LMCtrl::printIter ( const unsigned int verbose )

protectedvirtual

Dumps warning or status messages.

Parameters

verbose is a integer whose 32 bits are intended as follows. The lowest word (16 bits) progressively enables different levels of warning messages or status dump: the larger this value the more detailed is the output (0x####0000=>off by default). The highest word indicates how many successive calls to the dump shall be skipped in order to reduce the amount of information on the screen (ex: 0x0000####=>print all iterations, 0x0001####=>print one iteration and skip the next one, 0x0002####=> print one iteration and skip the next two).

Note: Angles are dumperd as degrees. Shall be implemented.

Implements iCub::iKin::iKinCtrl.

Definition at line 638 of file iKinInv.cpp.

◆ reset_mu()

void LMCtrl::reset_mu ( )

Sets the weighting factor mu equal to the initial value.

Definition at line 535 of file iKinInv.cpp.

◆ resetInt()

void iCub::iKin::LMCtrl::resetInt ( )

inline

Resets integral status at the current joint angles.

Definition at line 656 of file iKinInv.h.

◆ restart()

void LMCtrl::restart ( const yarp::sig::Vector & q0 )

virtual

Reinitializes the algorithm's internal state and resets the starting point.

Parameters

q0	is the new starting point.

Reimplemented from iCub::iKin::iKinCtrl.

Definition at line 628 of file iKinInv.cpp.

◆ setChainConstraints()

void LMCtrl::setChainConstraints ( bool _constrained )

virtual

Enables/Disables joint angles constraints.

Parameters

_constrained if true then constraints are applied.

Reimplemented from iCub::iKin::iKinCtrl.

Definition at line 497 of file iKinInv.cpp.

◆ test_convergence()

virtual bool iCub::iKin::LMCtrl::test_convergence ( const double tol_size )

inlinevirtual

Tests convergence by comparing the size of the algorithm internal structure (may be the gradient norm or the simplex size or whatever) to a certain tolerance.

Parameters

tol_size is tolerance to compare to. Shall be implemented.

Implements iCub::iKin::iKinCtrl.

Definition at line 650 of file iKinInv.h.

◆ update_mu()

double LMCtrl::update_mu ( )

protectedvirtual

Definition at line 543 of file iKinInv.cpp.

Member Data Documentation

◆ constrained

bool iCub::iKin::LMCtrl::constrained

protected

Definition at line 590 of file iKinInv.h.

◆ dist_old

double iCub::iKin::LMCtrl::dist_old

protected

Definition at line 603 of file iKinInv.h.

◆ gpm

yarp::sig::Vector iCub::iKin::LMCtrl::gpm

protected

Definition at line 593 of file iKinInv.h.

◆ I

ctrl::Integrator* iCub::iKin::LMCtrl::I

protected

Definition at line 588 of file iKinInv.h.

◆ mu

double iCub::iKin::LMCtrl::mu

protected

Definition at line 596 of file iKinInv.h.

◆ mu0

double iCub::iKin::LMCtrl::mu0

protected

Definition at line 597 of file iKinInv.h.

◆ mu_dec

double iCub::iKin::LMCtrl::mu_dec

protected

Definition at line 599 of file iKinInv.h.

◆ mu_inc

double iCub::iKin::LMCtrl::mu_inc

protected

Definition at line 598 of file iKinInv.h.

◆ mu_max

double iCub::iKin::LMCtrl::mu_max

protected

Definition at line 601 of file iKinInv.h.

◆ mu_min

double iCub::iKin::LMCtrl::mu_min

protected

Definition at line 600 of file iKinInv.h.

◆ pinvLM

yarp::sig::Matrix iCub::iKin::LMCtrl::pinvLM

protected

Definition at line 594 of file iKinInv.h.

◆ qdot

yarp::sig::Vector iCub::iKin::LMCtrl::qdot

protected

Definition at line 592 of file iKinInv.h.

◆ svMin

double iCub::iKin::LMCtrl::svMin

protected

Definition at line 604 of file iKinInv.h.

◆ svThres

double iCub::iKin::LMCtrl::svThres

protected

Definition at line 605 of file iKinInv.h.

◆ Ts

double iCub::iKin::LMCtrl::Ts

protected

Definition at line 587 of file iKinInv.h.

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

icub-main/src/libraries/iKin/include/iCub/iKin/iKinInv.h
icub-main/src/libraries/iKin/src/iKinInv.cpp

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ LMCtrl()

◆ ~LMCtrl()

Member Function Documentation

◆ computeGPM()

◆ deadLockRecoveryFcn()

◆ get_gpm()

◆ get_mu()

◆ get_qdot()

◆ getAlgoName()

◆ inTargetFcn()

◆ iterate()

◆ pinv()

◆ printIter()

◆ reset_mu()

◆ resetInt()

◆ restart()

◆ setChainConstraints()

◆ test_convergence()

◆ update_mu()

Member Data Documentation

◆ constrained

◆ dist_old

◆ gpm

◆ I

◆ mu

◆ mu0

◆ mu_dec

◆ mu_inc

◆ mu_max

◆ mu_min

◆ pinvLM

◆ qdot

◆ svMin

◆ svThres

◆ Ts