This class gives the abstract definition of a feature. More...

#include <sot/core/feature-abstract.hh>

Inheritance diagram for dynamicgraph::sot::FeatureAbstract:

Public Member Functions
virtual const std::string &	getClassName (void) const
	Returns the name class.
void	featureRegistration (void)
	Register the feature in the stack of tasks.
void	initCommands (void)
	FeatureAbstract (const std::string &name)
	Default constructor: the name of the class should be given.
virtual	~FeatureAbstract (void)
	Default destructor.
Methods returning the dimension of the feature.
virtual unsigned int &	getDimension (unsigned int &res, int time)=0
	Verbose method.
unsigned int	getDimension (int time)
	Short method.
unsigned int	getDimension (void) const
	Shortest method.
Methods to control internal computation.
The main idea is that some feature may have a lower frequency than the internal control loop. In this case, the methods for computation are called only when needed.
virtual ml::Vector &	computeError (ml::Vector &res, int time)=0
	Compute the error between the desired feature and the current value of the feature measured or deduced from the robot state.
virtual ml::Matrix &	computeJacobian (ml::Matrix &res, int time)=0
	Compute the Jacobian of the error according the robot state.
virtual ml::Vector &	computeErrorDot (ml::Vector &res, int time)
	Callback for signal errordotSOUT.
Reference
virtual void	setReference (FeatureAbstract *sdes)=0
virtual void	unsetReference (void)
virtual const FeatureAbstract *	getReferenceAbstract (void) const =0
virtual FeatureAbstract *	getReferenceAbstract (void)=0
virtual bool	isReferenceSet (void) const
virtual void	addDependenciesFromReference (void)=0
virtual void	removeDependenciesFromReference (void)=0
void	setReferenceByName (const std::string &name)
std::string	getReferenceByName (void) const
Public Attributes
Input signals:
SignalPtr< Flags, int >	selectionSIN
	This vector specifies which dimension are used to perform the computation. For instance let us assume that the feature is a 3D point. If only the Y-axis should be used for computing error, activation and Jacobian, then the vector to specify is .
SignalPtr< ml::Vector, int >	errordotSIN
	Derivative of the reference value.
Static Public Attributes
static const std::string	CLASS_NAME
	Store the name of the class.
Output signals:
SignalTimeDependent < ml::Vector, int >	errorSOUT
	This signal returns the error between the desired value and the current value : ${\bf s}^*(t) - {\bf s}(t)$ .
SignalTimeDependent < ml::Vector, int >	errordotSOUT
	Derivative of the reference value.
SignalTimeDependent < ml::Matrix, int >	jacobianSOUT
	This signal returns the Jacobian of the current value according to the robot state: $J(t) = \frac{\delta{\bf s}^*(t)}{\delta {\bf q}(t)}$ .
SignalTimeDependent< unsigned int, int >	dimensionSOUT
	Returns the dimension of the feature as an output signal.
virtual std::ostream &	writeGraph (std::ostream &os) const
	This method write a graph description on the file named FileName.
virtual bool	withErrorDot (void) const SOT_CORE_DEPRECATED
	Return true for children that provide the errordot output signal.
virtual SignalTimeDependent < ml::Vector, int > &	getErrorDot ()

Detailed Description

This class gives the abstract definition of a feature.

In short, a feature is a data evolving according to time. It is defined by a vector ${\bf s}(t) \in \mathbb{R}^n$ where $ t $ is the time. By default a feature has a desired ${\bf s}^*(t)$ . ${\bf s}^*$ is provided by another feature of the same type called reference. The feature is in charge of collecting its own current state. A feature is supposed to compute an error between its current state and the desired one: $e(t) = {\bf s}^*(t) - {\bf s}(t)$ . A feature is supposed to compute a Jacobian according to the robot state vector $\frac{\delta {\bf s}(t)}{\delta {\bf q}(t)}$ .

The task is in general computed from the value of the feature at the current instant $f(q(t),t)$ , the Jacobian $J$ and evolution of the feature with respect to time: $\frac{\partial f}{\partial t}$ .

Feature diagram: Feature types derive from FeatureAbstract. Each feature has a reference of the same type and compute an error by comparing errorSIN signals from itself and from the reference.

Constructor & Destructor Documentation

dynamicgraph::sot::FeatureAbstract::FeatureAbstract ( const std::string & name )

Default constructor: the name of the class should be given.

virtual dynamicgraph::sot::FeatureAbstract::~FeatureAbstract ( void ) [inline, virtual]

Default destructor.

Member Function Documentation

virtual void dynamicgraph::sot::FeatureAbstract::addDependenciesFromReference ( void ) [pure virtual]

virtual ml::Vector& dynamicgraph::sot::FeatureAbstract::computeError	(	ml::Vector &	res,
		int	time
	)		`[pure virtual]`

Compute the error between the desired feature and the current value of the feature measured or deduced from the robot state.

[out] res: The error will be set into res.

[in] time: The time at which the error is computed.

Returns:: The vector res with the appropriate value.

Implemented in dynamicgraph::sot::FeatureGeneric, dynamicgraph::sot::Feature1D, dynamicgraph::sot::FeaturePoint6d, dynamicgraph::sot::FeatureJointLimits, dynamicgraph::sot::FeaturePoint6dRelative, dynamicgraph::sot::FeatureLineDistance, dynamicgraph::sot::FeatureVisualPoint, dynamicgraph::sot::FeatureVector3, dynamicgraph::sot::FeaturePosture, and dynamicgraph::sot::FeaturePosture.

virtual ml::Vector& dynamicgraph::sot::FeatureAbstract::computeErrorDot	(	ml::Vector &	res,
		int	time
	)		`[virtual]`

Callback for signal errordotSOUT.

Copy components of the input signal errordotSIN defined by selection flag selectionSIN.

Reimplemented in dynamicgraph::sot::FeaturePoint6dRelative.

virtual ml::Matrix& dynamicgraph::sot::FeatureAbstract::computeJacobian	(	ml::Matrix &	res,
		int	time
	)		`[pure virtual]`

Compute the Jacobian of the error according the robot state.

[out] res: The matrix in which the error will be written.

Returns:: The matrix res with the appropriate values.

Implemented in dynamicgraph::sot::FeatureGeneric, dynamicgraph::sot::Feature1D, dynamicgraph::sot::FeaturePoint6d, dynamicgraph::sot::FeatureJointLimits, dynamicgraph::sot::FeaturePoint6dRelative, dynamicgraph::sot::FeatureLineDistance, dynamicgraph::sot::FeatureVisualPoint, dynamicgraph::sot::FeatureVector3, dynamicgraph::sot::FeaturePosture, and dynamicgraph::sot::FeaturePosture.

void dynamicgraph::sot::FeatureAbstract::featureRegistration ( void )

Register the feature in the stack of tasks.

virtual const std::string& dynamicgraph::sot::FeatureAbstract::getClassName ( void ) const [inline, virtual]

Returns the name class.

Implements dynamicgraph::Entity.

Reimplemented in dynamicgraph::sot::FeatureGeneric, dynamicgraph::sot::Feature1D, dynamicgraph::sot::FeaturePoint6d, dynamicgraph::sot::FeaturePoint6dRelative, dynamicgraph::sot::FeatureLineDistance, dynamicgraph::sot::FeatureVector3, dynamicgraph::sot::FeatureJointLimits, dynamicgraph::sot::FeatureVisualPoint, dynamicgraph::sot::FeatureTask, and dynamicgraph::sot::FeaturePosture.

virtual unsigned int& dynamicgraph::sot::FeatureAbstract::getDimension	(	unsigned int &	res,
		int	time
	)		`[pure virtual]`

Verbose method.

res: The integer in which the dimension will be return.

time: The time at which the feature should be considered.

Returns:: Dimension of the feature.

Note:: Be careful with features changing their dimension according to time.

Implemented in dynamicgraph::sot::FeatureGeneric, dynamicgraph::sot::Feature1D, dynamicgraph::sot::FeaturePoint6d, dynamicgraph::sot::FeatureJointLimits, dynamicgraph::sot::FeatureLineDistance, dynamicgraph::sot::FeatureVisualPoint, dynamicgraph::sot::FeatureVector3, dynamicgraph::sot::FeaturePosture, and dynamicgraph::sot::FeaturePosture.

unsigned int dynamicgraph::sot::FeatureAbstract::getDimension ( int time ) [inline]

Short method.

time: The time at which the feature should be considered.

Returns:: Dimension of the feature.

Note:: Be careful with features changing their dimension according to time.

References getDimension().

Referenced by getDimension().

unsigned int dynamicgraph::sot::FeatureAbstract::getDimension ( void ) const [inline]

Shortest method.

Returns:: Dimension of the feature.

Note:: The feature is not changing its dimension according to time.

virtual SignalTimeDependent<ml::Vector,int>& dynamicgraph::sot::FeatureAbstract::getErrorDot ( ) [inline, virtual]

virtual const FeatureAbstract* dynamicgraph::sot::FeatureAbstract::getReferenceAbstract ( void ) const [pure virtual]

virtual FeatureAbstract* dynamicgraph::sot::FeatureAbstract::getReferenceAbstract ( void ) [pure virtual]

std::string dynamicgraph::sot::FeatureAbstract::getReferenceByName ( void ) const

void dynamicgraph::sot::FeatureAbstract::initCommands ( void )

Reimplemented in dynamicgraph::sot::FeaturePoint6dRelative.

virtual bool dynamicgraph::sot::FeatureAbstract::isReferenceSet ( void ) const [inline, virtual]

virtual void dynamicgraph::sot::FeatureAbstract::removeDependenciesFromReference ( void ) [pure virtual]

virtual void dynamicgraph::sot::FeatureAbstract::setReference ( FeatureAbstract * sdes ) [pure virtual]

void dynamicgraph::sot::FeatureAbstract::setReferenceByName ( const std::string & name )

virtual void dynamicgraph::sot::FeatureAbstract::unsetReference ( void ) [inline, virtual]

virtual bool dynamicgraph::sot::FeatureAbstract::withErrorDot ( void ) const [inline, virtual]

Return true for children that provide the errordot output signal.

virtual std::ostream& dynamicgraph::sot::FeatureAbstract::writeGraph ( std::ostream & os ) const [virtual]

This method write a graph description on the file named FileName.

Reimplemented from dynamicgraph::Entity.

Member Data Documentation

const std::string dynamicgraph::sot::FeatureAbstract::CLASS_NAME [static]

Store the name of the class.

Reimplemented in dynamicgraph::sot::FeatureGeneric, dynamicgraph::sot::FeaturePoint6d, dynamicgraph::sot::Feature1D, dynamicgraph::sot::FeaturePoint6dRelative, dynamicgraph::sot::FeatureLineDistance, dynamicgraph::sot::FeatureVector3, dynamicgraph::sot::FeatureJointLimits, dynamicgraph::sot::FeatureVisualPoint, dynamicgraph::sot::FeatureTask, and dynamicgraph::sot::FeaturePosture.

SignalTimeDependent<unsigned int,int> dynamicgraph::sot::FeatureAbstract::dimensionSOUT

Returns the dimension of the feature as an output signal.

SignalPtr< ml::Vector,int > dynamicgraph::sot::FeatureAbstract::errordotSIN

Derivative of the reference value.

SignalTimeDependent< ml::Vector,int > dynamicgraph::sot::FeatureAbstract::errordotSOUT

Derivative of the reference value.

SignalTimeDependent<ml::Vector,int> dynamicgraph::sot::FeatureAbstract::errorSOUT

This signal returns the error between the desired value and the current value : ${\bf s}^*(t) - {\bf s}(t)$ .

SignalTimeDependent<ml::Matrix,int> dynamicgraph::sot::FeatureAbstract::jacobianSOUT

This signal returns the Jacobian of the current value according to the robot state: $J(t) = \frac{\delta{\bf s}^*(t)}{\delta {\bf q}(t)}$ .

SignalPtr< Flags,int > dynamicgraph::sot::FeatureAbstract::selectionSIN

This vector specifies which dimension are used to perform the computation. For instance let us assume that the feature is a 3D point. If only the Y-axis should be used for computing error, activation and Jacobian, then the vector to specify is $ [ 0 1 0] $ .

Public Member Functions

Public Attributes

Static Public Attributes

Output signals:

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation