A base class for IkFast-based analytical inverse kinematics classes. More...

#include <IkFast.hpp>

Inheritance diagram for dart::dynamics::IkFast:

Collaboration diagram for dart::dynamics::IkFast:

Public Types
enum	IkType { TRANSFORM_6D, ROTATION_3D, TRANSLATION_3D, DIRECTION_3D, RAY_4D, LOOKAT_3D, TRANSLATION_DIRECTION_5D, TRANSLATION_XY_2D, TRANSLATION_XY_ORIENTATION_3D, TRANSLATION_LOCAL_GLOBAL_6D, TRANSLATION_X_AXIS_ANGLE_4D, TRANSLATION_Y_AXIS_ANGLE_4D, TRANSLATION_Z_AXIS_ANGLE_4D, TRANSLATION_X_AXIS_ANGLE_Z_NORM_4D, TRANSLATION_Y_AXIS_ANGLE_X_NORM_4D, TRANSLATION_Z_AXIS_ANGLE_Y_NORM_4D, UNKNOWN }
	Inverse kinematics types supported by IkFast. More...

Public Types inherited from dart::dynamics::InverseKinematics::Analytical
enum	Validity_t { VALID = 0, OUT_OF_REACH = 1 << 0, LIMIT_VIOLATED = 1 << 1 }
	Bitwise enumerations that are used to describe some properties of each solution produced by the analytical IK. More...

enum	ExtraDofUtilization { UNUSED = 0, PRE_ANALYTICAL, POST_ANALYTICAL, PRE_AND_POST_ANALYTICAL }
	If there are extra DOFs in the IK module which your Analytical solver implementation does not make use of, those DOFs can be used to supplement the analytical solver using Jacobian transpose iteration. More...

typedef std::function< bool(const Eigen::VectorXd &_better, const Eigen::VectorXd &_worse, const InverseKinematics *_ik)>	QualityComparison

Public Member Functions
	IkFast (InverseKinematics *ik, const std::vector< std::size_t > &dofMap, const std::vector< std::size_t > &freeDofMap, const std::string &methodName="IKFast", const Analytical::Properties &properties=Analytical::Properties())
	Constructor. More...

const std::vector< InverseKinematics::Analytical::Solution > &	computeSolutions (const Eigen::Isometry3d &desiredBodyTf) override
	Use this function to fill the entries of the mSolutions variable. More...

Eigen::Isometry3d	computeFk (const Eigen::VectorXd &parameters)
	Computes forward kinematics given joint positions where the dimension is the same as getNumJoints2(). More...

const std::vector< std::size_t > &	getDofs () const override
	Returns the indices of the DegreeOfFreedoms that are part of the joints that IkFast solves for. More...

const std::vector< std::size_t > &	getFreeDofs () const
	Returns the indices of the DegreeOfFreedoms that are part of the joints that IkFast solves but the values should be set by the user in prior. More...

virtual bool	isConfigured () const
	Returns true if this IkFast is ready to solve.

std::size_t	getNumFreeParameters2 () const
	Returns the number of free parameters users has to set apriori.

std::size_t	getNumJoints2 () const
	Returns the total number of indices of the chane.

IkType	getIkType2 () const
	Returns the IK type.

const std::string	getKinematicsHash2 () const
	Returns a hash of all the chain values used for double checking that the correct IK is used. More...

std::string	getIkFastVersion2 () const
	Returns the IkFast version used to generate this file.

Public Member Functions inherited from dart::dynamics::InverseKinematics::Analytical
	Analytical (InverseKinematics *_ik, const std::string &_methodName, const Properties &_properties)
	Constructor.

virtual	~Analytical ()=default
	Virtual destructor.

const std::vector< Solution > &	getSolutions ()
	Get the solutions for this IK module, along with a tag indicating whether each solution is valid. More...

const std::vector< Solution > &	getSolutions (const Eigen::Isometry3d &_desiredTf)
	Get the solutions for this IK module, along with a tag indicating whether each solution is valid. More...

void	computeGradient (const Eigen::Vector6d &_error, Eigen::VectorXd &_grad) override
	You should not need to override this function. More...

void	setPositions (const Eigen::VectorXd &_config)
	Set the configuration of the DOFs. More...

Eigen::VectorXd	getPositions () const
	Get the configuration of the DOFs. More...

void	setExtraDofUtilization (ExtraDofUtilization _utilization)
	Set how you want extra DOFs to be utilized by the IK module.

ExtraDofUtilization	getExtraDofUtilization () const
	Get how extra DOFs are being utilized by the IK module.

void	setExtraErrorLengthClamp (double _clamp)
	Set how much to clamp the error vector that gets applied to extra DOFs.

double	getExtraErrorLengthClamp () const
	Get how much we will clamp the error vector that gets applied to extra DOFs.

void	setQualityComparisonFunction (const QualityComparison &_func)
	Set the function that will be used to compare the qualities of two solutions. More...

void	resetQualityComparisonFunction ()
	Reset the quality comparison function to the default method.

Properties	getAnalyticalProperties () const
	Get the Properties for this Analytical class.

void	constructDofMap ()
	Construct a mapping from the DOFs of getDofs() to their indices within the Node's list of dependent DOFs. More...

Public Member Functions inherited from dart::dynamics::InverseKinematics::GradientMethod
	GradientMethod (InverseKinematics *_ik, const std::string &_methodName, const Properties &_properties)
	Constructor.

virtual	~GradientMethod ()=default
	Virtual destructor.

virtual std::unique_ptr< GradientMethod >	clone (InverseKinematics *_newIK) const =0
	Enable this GradientMethod to be cloned to a new IK module.

void	evalGradient (const Eigen::VectorXd &_q, Eigen::Map< Eigen::VectorXd > _grad)
	This function is used to handle caching the gradient vector and interfacing with the solver. More...

const std::string &	getMethodName () const
	Get the name of this GradientMethod.

void	clampGradient (Eigen::VectorXd &_grad) const
	Clamp the gradient based on the clamp settings of this GradientMethod.

void	setComponentWiseClamp (double _clamp=DefaultIKGradientComponentClamp)
	Set the component-wise clamp for this GradientMethod. More...

double	getComponentWiseClamp () const
	Get the component-wise clamp for this GradientMethod.

void	applyWeights (Eigen::VectorXd &_grad) const
	Apply weights to the gradient based on the weight settings of this GradientMethod. More...

void	setComponentWeights (const Eigen::VectorXd &_weights)
	Set the weights that will be applied to each component of the gradient. More...

const Eigen::VectorXd &	getComponentWeights () const
	Get the weights of this GradientMethod.

void	convertJacobianMethodOutputToGradient (Eigen::VectorXd &grad, const std::vector< std::size_t > &dofs)
	Convert the gradient that gets generated by Jacobian methods into a gradient that can be used by a GradientDescentSolver. More...

Properties	getGradientMethodProperties () const
	Get the Properties of this GradientMethod.

void	clearCache ()
	Clear the cache to force the gradient to be recomputed. More...

InverseKinematics *	getIK ()
	Returns the IK module that this GradientMethod belongs to.

const InverseKinematics *	getIK () const
	Returns the IK module that this GradientMethod belongs to.

Public Member Functions inherited from dart::common::Subject
virtual	~Subject ()
	Destructor will notify all Observers that it is destructing.

Protected Member Functions
virtual int	getNumFreeParameters () const =0
	Returns the number of free parameters users has to set apriori.

virtual int *	getFreeParameters () const =0
	Returns the indicies of the free parameters indexed by the chain joints.

virtual int	getNumJoints () const =0
	Returns the total number of indices of the chane.

virtual int	getIkRealSize () const =0
	Returns the size in bytes of the configured number type.

virtual int	getIkType () const =0
	Returns the IK type.

virtual bool	computeIk (const IkReal targetTranspose, const IkReal targetRotation, const IkReal *pfree, ikfast::IkSolutionListBase< IkReal > &solutions)=0
	Computes the inverse kinematics solutions using the generated IKFast code.

virtual void	computeFk (const IkReal parameters, IkReal targetTranspose, IkReal *targetRotation)=0
	Computes the forward kinematics solutions using the generated IKFast code.

virtual const char *	getKinematicsHash ()=0
	Returns a hash of all the chain values used for double checking that the correct IK is used. More...

virtual const char *	getIkFastVersion ()=0
	Returns the IkFast version used to generate this file.

virtual void	configure () const
	Configure IkFast. More...

Protected Member Functions inherited from dart::dynamics::InverseKinematics::Analytical
virtual void	addExtraDofGradient (Eigen::VectorXd &grad, const Eigen::Vector6d &error, ExtraDofUtilization utilization)
	This function will compute a gradient which utilizes the extra DOFs that go unused by the Analytical solution and then it will add the components of that gradient to the output parameter: grad. More...

void	checkSolutionJointLimits ()
	Go through the mSolutions vector and tag entries with LIMIT_VIOLATED if any components of their configuration are outside of their position limits. More...

Protected Member Functions inherited from dart::common::Subject
void	sendDestructionNotification () const
	Send a destruction notification to all Observers. More...

void	addObserver (Observer *_observer) const
	Add an Observer to the list of Observers.

void	removeObserver (Observer *_observer) const
	Remove an Observer from the list of Observers.

Protected Attributes
std::vector< double >	mFreeParams

bool	mConfigured
	True if this IkFast is ready to solve.

std::vector< std::size_t >	mDofs
	Indices of the DegreeOfFreedoms associated to the variable parameters of this IkFast. More...

std::vector< std::size_t >	mFreeDofs
	Indices of the DegreeOfFreedoms associated to the free parameters of this IkFast. More...

Protected Attributes inherited from dart::dynamics::InverseKinematics::Analytical
std::vector< Solution >	mSolutions
	Vector of solutions.

UniqueProperties	mAnalyticalP
	Properties for this Analytical IK solver.

Protected Attributes inherited from dart::dynamics::InverseKinematics::GradientMethod
common::sub_ptr< InverseKinematics >	mIK
	The IK module that this GradientMethod belongs to.

std::string	mMethodName
	The name of this method.

Eigen::VectorXd	mLastPositions
	The last positions that was passed to this GradientMethod.

Eigen::VectorXd	mLastGradient
	The last gradient that was computed by this GradientMethod.

Properties	mGradientP
	Properties for this GradientMethod.

Protected Attributes inherited from dart::common::Subject
std::set< Observer * >	mObservers
	List of current Observers.

Detailed Description

A base class for IkFast-based analytical inverse kinematics classes.

The detail of IkFast can be found here: http://openrave.org/docs/0.8.2/openravepy/ikfast/

Member Enumeration Documentation

◆ IkType

enum dart::dynamics::IkFast::IkType

Inverse kinematics types supported by IkFast.

Enumerator
TRANSFORM_6D	End effector reaches desired 6D transformation.
ROTATION_3D	End effector reaches desired 3D rotation.
TRANSLATION_3D	End effector origin reaches desired 3D translation.
DIRECTION_3D	Direction on end effector coordinate system reaches desired direction.
RAY_4D	Ray on end effector coordinate system reaches desired global ray.
LOOKAT_3D	Direction on end effector coordinate system points to desired 3D position.
TRANSLATION_DIRECTION_5D	End effector origin and direction reaches desired 3D translation and direction. Can be thought of as Ray IK where the origin of the ray must coincide.
TRANSLATION_XY_2D	End effector origin reaches desired XY translation position, Z is ignored. The coordinate system with relative to the base link.
TRANSLATION_XY_ORIENTATION_3D	2D translation along XY plane and 1D rotation around Z axis. The offset of the rotation is measured starting at +X, so at +X is it 0, at +Y it is pi/2.
TRANSLATION_LOCAL_GLOBAL_6D	Local point on end effector origin reaches desired 3D global point. Because both local point and global point can be specified, there are 6 values.
TRANSLATION_X_AXIS_ANGLE_4D	End effector origin reaches desired 3D translation, manipulator direction makes a specific angle with x-axis (defined in the manipulator base link’s coordinate system)
TRANSLATION_Y_AXIS_ANGLE_4D	End effector origin reaches desired 3D translation, manipulator direction makes a specific angle with y-axis (defined in the manipulator base link’s coordinate system)
TRANSLATION_Z_AXIS_ANGLE_4D	End effector origin reaches desired 3D translation, manipulator direction makes a specific angle with z-axis (defined in the manipulator base link’s coordinate system)
TRANSLATION_X_AXIS_ANGLE_Z_NORM_4D	End effector origin reaches desired 3D translation, manipulator direction needs to be orthogonal to z-axis and be rotated at a certain angle starting from the x-axis (defined in the manipulator base link's coordinate system)
TRANSLATION_Y_AXIS_ANGLE_X_NORM_4D	End effector origin reaches desired 3D translation, manipulator direction needs to be orthogonal to z-axis and be rotated at a certain angle starting from the y-axis (defined in the manipulator base link's coordinate system)
TRANSLATION_Z_AXIS_ANGLE_Y_NORM_4D	End effector origin reaches desired 3D translation, manipulator direction needs to be orthogonal to z-axis and be rotated at a certain angle starting from the z-axis (defined in the manipulator base link's coordinate system)

Constructor & Destructor Documentation

◆ IkFast()

dart::dynamics::IkFast::IkFast	(	InverseKinematics *	ik,
		const std::vector< std::size_t > &	dofMap,
		const std::vector< std::size_t > &	freeDofMap,
		const std::string &	methodName = `"IKFast"`,
		const Analytical::Properties &	properties = `Analytical::Properties()`
	)

Constructor.

Parameters

[in]	ik	The parent InverseKinematics solver that is associated with this gradient method.
[in]	dofMap	The indices to the degrees-of-freedom that will be solved by IkFast. The number of DOFs can be varied depending on the IkFast solvers.
[in]	freeDofMap	The indices to the DOFs that are not solved by the IkFast solver. The values of these DOFs should be set properly.
[in]	methodName	The name of this analytical inverse kinematics method.
[in]	properties	Properties of InverseKinematics::Analytical.

Member Function Documentation

◆ computeFk()

Eigen::Isometry3d dart::dynamics::IkFast::computeFk ( const Eigen::VectorXd & parameters )

Computes forward kinematics given joint positions where the dimension is the same as getNumJoints2().

◆ computeSolutions()

auto dart::dynamics::IkFast::computeSolutions ( const Eigen::Isometry3d & _desiredBodyTf )

overridevirtual

Use this function to fill the entries of the mSolutions variable.

Be sure to clear the mSolutions vector at the start, and to also return the mSolutions vector at the end. Note that you are not expected to evaluate any of the solutions for their quality. However, you should set the Solution::mValidity flag to OUT_OF_REACH for each solution that does not actually reach the desired transform, and you should call checkSolutionJointLimits() and the end of the function, which will set the LIMIT_VIOLATED flags of any configurations that are outside of the position limits.

Implements dart::dynamics::InverseKinematics::Analytical.

◆ configure()

void dart::dynamics::IkFast::configure ( ) const

protectedvirtual

Configure IkFast.

If it's successfully configured, isConfigured() returns true.

Reimplemented in dart::dynamics::SharedLibraryIkFast.

◆ getDofs()

auto dart::dynamics::IkFast::getDofs ( ) const

overridevirtual

Returns the indices of the DegreeOfFreedoms that are part of the joints that IkFast solves for.

Implements dart::dynamics::InverseKinematics::Analytical.

◆ getFreeDofs()

const std::vector< std::size_t > & dart::dynamics::IkFast::getFreeDofs ( ) const

Returns the indices of the DegreeOfFreedoms that are part of the joints that IkFast solves but the values should be set by the user in prior.

◆ getKinematicsHash()

virtual const char* dart::dynamics::IkFast::getKinematicsHash ( )

protectedpure virtual

Returns a hash of all the chain values used for double checking that the correct IK is used.

Implemented in dart::dynamics::SharedLibraryIkFast, and SharedLibraryWamIkFast.

◆ getKinematicsHash2()

const std::string dart::dynamics::IkFast::getKinematicsHash2 ( ) const

Returns a hash of all the chain values used for double checking that the correct IK is used.

Member Data Documentation

◆ mDofs

std::vector<std::size_t> dart::dynamics::IkFast::mDofs

mutableprotected

Indices of the DegreeOfFreedoms associated to the variable parameters of this IkFast.

◆ mFreeDofs

std::vector<std::size_t> dart::dynamics::IkFast::mFreeDofs