OpenSim::CMC_Task Class Reference

An abstract base class for specifying a task objective for a dynamic simulation. More...

#include <CMC_Task.h>

Inheritance diagram for OpenSim::CMC_Task:

Public Member Functions
	CMC_Task ()
	Construct a default track object for a specified model.
	CMC_Task (const CMC_Task &aTaskObject)
	Copy constructor.
virtual	~CMC_Task ()
	Destructor.
virtual Object *	copy () const =0
	Construct and return a copy of this object.
CMC_Task &	operator= (const CMC_Task &aTaskObject)
	Assignment operator.
virtual void	setModel (Model &aModel)
	Set the model to which this track object applies.
Model *	getModel () const
	Get the model to which this track object applies.
void	setOn (bool aTrueFalse)
	Turn this track object on or off.
bool	getOn () const
	Get whether or not this track object is on.
void	setWRTBodyName (std::string aBodyName)
	Set the body with respect to (WRT) which the track goals are specified.
std::string	getWRTBodyName () const
	Get the body with respect to (WRT) which the track goals are specified.
void	setExpressBodyName (std::string aBodyName)
	Set the body in which the track goals are expressed.
std::string	getExpressBodyName () const
	Get the body in which the track goals are expressed.
void	setActive (bool a0, bool a1=false, bool a2=false)
	Set whether or not track goals are active.
bool	getActive (int aWhich) const
	Get whether a specified track goal is active.
void	setWeight (double aW0, double aW1=0.0, double aW2=0.0)
	Set the weight of each track goal.
double	getWeight (int aWhich) const
	Get the weight of each track goal.
void	setKP (double aK0, double aK1=0.0, double aK2=0.0)
	Set the position gains for each track goal.
double	getKP (int aWhich) const
	Get the position gain for a specified track goal.
void	setKV (double aK0, double aK1=0.0, double aK2=0.0)
	Set the velocity gains for each track goal.
double	getKV (int aWhich) const
	Get the velocity gain for a specified track goal.
void	setKA (double aK0, double aK1=0.0, double aK2=0.0)
	Set the acceleration gains for each track goal.
double	getKA (int aWhich) const
	Get the acceleration gain for a specified track goal.
void	setDirection_0 (const SimTK::Vec3 &aR)
	Set the direction of track goal 0.
void	getDirection_0 (SimTK::Vec3 &rR) const
	Get the direction of track goal 0.
void	setDirection_1 (const SimTK::Vec3 &aR)
	Set the direction of track goal 1.
void	getDirection_1 (SimTK::Vec3 &rR) const
	Get the direction of track goal 1.
void	setDirection_2 (const SimTK::Vec3 &aR)
	Set the direction of track goal 2.
void	getDirection_2 (SimTK::Vec3 &rR) const
	Get the direction of track goal 2.
int	getNumTaskFunctions () const
	Get the number of position track functions.
void	setTaskFunctions (Function aF0, Function aF1=NULL, Function *aF2=NULL)
	Set the track functions.
Function *	getTaskFunction (int aWhich) const
	Get a specified track function.
void	setTaskFunctionsForVelocity (Function aF0, Function aF1=NULL, Function *aF2=NULL)
	Set the velocity track functions.
Function *	getTaskFunctionForVelocity (int aWhich) const
	Get a specified velocity track function.
void	setTaskFunctionsForAcceleration (Function aF0, Function aF1=NULL, Function *aF2=NULL)
	Set the acceleration track functions.
Function *	getTaskFunctionForAcceleration (int aWhich) const
	Get a specified acceleration track function.
double	getTaskPosition (int aWhich, double aT) const
	Get the task position.
double	getTaskVelocity (int aWhich, double aT) const
	Get the task velocity.
double	getTaskAcceleration (int aWhich, double aT) const
	Get the task acceleration.
void	setPositionErrorLast (double aE0, double aE1=0.0, double aE2=0.0)
	Set the last achieved position error.
double	getPositionErrorLast (int aWhich) const
	Get the last achieved position error.
void	setVelocityErrorLast (double aE0, double aE1=0.0, double aE2=0.0)
	Set the last achieved velocity error.
double	getVelocityErrorLast (int aWhich) const
	Get the last achieved velocity error.
double	getPositionError (int aWhich) const
	Get the position track error of a specified track goal.
double	getVelocityError (int aWhich) const
	Get the velocity track error of a specified track goal.
double	getDesiredAcceleration (int aWhich) const
	Get the desired acceleration of a specified track goal.
double	getAcceleration (int aWhich) const
	Get the acceleration of a specified track goal.
virtual void	computeErrors (const SimTK::State &s, double aT)=0
virtual void	computeDesiredAccelerations (const SimTK::State &s, double aT)=0
virtual void	computeDesiredAccelerations (const SimTK::State &s, double aTI, double aTF)=0
virtual void	computeAccelerations (const SimTK::State &s)=0
virtual void	computeJacobian ()
	Compute the Jacobian.
virtual void	computeEffectiveMassMatrix ()
	Compute the effective mass matrix.
virtual void	updateFromXMLNode ()
	Update this object based on its XML node.
Protected Attributes
PropertyBool	_propOn
	Property to indicate on or off state.
PropertyStr	_propWRTBodyName
	Body with respect to which the task goals are specified.
PropertyStr	_propExpressBodyName
	Body frame in which the task goals are expressed.
PropertyBoolArray	_propActive
	Property to specify the active task goals.
PropertyDblArray	_propW
	Weights of the task goals.
PropertyDblArray	_propKP
	Position error feedback gain.
PropertyDblArray	_propKV
	Velocity error feedback gain.
PropertyDblArray	_propKA
	Feedforward acceleration gain.
PropertyDblVec3	_propR0
	Directions of the task goal 0.
PropertyDblVec3	_propR1
	Directions of the task goal 1.
PropertyDblVec3	_propR2
	Directions of the task goal 2.
bool &	_on
	Reference to the value of the on property.
std::string &	_wrtBodyName
	Reference to the value of the WRTBody property.
std::string &	_expressBodyName
	Reference to the value of the ExpressBody property.
Array< bool > &	_active
	Reference to the value of the Active property.
Array< double > &	_w
	Reference to the value of the Weight property.
Array< double > &	_kp
	Reference to the value of the KP property.
Array< double > &	_kv
	Reference to the value of the KV property.
Array< double > &	_ka
	Reference to the value of the KA property.
SimTK::Vec3 &	_r0
	Reference to the value of the R0 property.
SimTK::Vec3 &	_r1
	Reference to the value of the R1 property.
SimTK::Vec3 &	_r2
	Reference to the value of the R2 property.
Model *	_model
	Model.
int	_nTrk
	Number of task functions.
Function *	_pTrk [3]
	Position task functions.
Function *	_vTrk [3]
	Velocity task functions.
Function *	_aTrk [3]
	Acceleration task functions.
SimTK::Vec3	_pErrLast
	Last position error.
SimTK::Vec3	_pErr
	Position error.
SimTK::Vec3	_vErrLast
	Last velocity error.
SimTK::Vec3	_vErr
	Velocity error.
SimTK::Vec3	_aDes
	Desired accelerations.
SimTK::Vec3	_a
	Accelerations.
double *	_j
	Jacobian.
double *	_m
	Effective mass matrix.

Detailed Description

An abstract base class for specifying a task objective for a dynamic simulation.

This class supports joint, point, and orientation task objectives. Specfic implementations for these kinds of control tasks should inherit from this class.

Author:: Frank C. Anderson

Version:: 1.0

Constructor & Destructor Documentation

CMC_Task::CMC_Task ( )

Construct a default track object for a specified model.

CMC_Task::CMC_Task ( const CMC_Task & aTask )

Copy constructor.

Parameters:

aTask

Task object to be copied.

CMC_Task::~CMC_Task ( ) [virtual]

Destructor.

Member Function Documentation

virtual void OpenSim::CMC_Task::computeAccelerations ( const SimTK::State & s ) [pure virtual]

Implemented in OpenSim::CMC_Joint, and OpenSim::CMC_Point.

virtual void OpenSim::CMC_Task::computeDesiredAccelerations	(	const SimTK::State &	s,
		double	aTI,
		double	aTF
	)			`[pure virtual]`

Implemented in OpenSim::CMC_Joint, and OpenSim::CMC_Point.

virtual void OpenSim::CMC_Task::computeDesiredAccelerations	(	const SimTK::State &	s,
		double	aT
	)			`[pure virtual]`

Implemented in OpenSim::CMC_Joint, OpenSim::CMC_Point, and OpenSim::SMC_Joint.

void CMC_Task::computeEffectiveMassMatrix ( ) [virtual]

Compute the effective mass matrix.

Reimplemented in OpenSim::CMC_Orientation.

virtual void OpenSim::CMC_Task::computeErrors	(	const SimTK::State &	s,
		double	aT
	)			`[pure virtual]`

Implemented in OpenSim::CMC_Joint, and OpenSim::CMC_Point.

void CMC_Task::computeJacobian ( ) [virtual]

Compute the Jacobian.

Reimplemented in OpenSim::CMC_Orientation.

virtual Object* OpenSim::CMC_Task::copy ( ) const [pure virtual]

Construct and return a copy of this object.

The object is allocated using the new operator, so the caller is responsible for deleting the returned object.

Returns:: Copy of this object.

Reimplemented from OpenSim::Object.

Implemented in OpenSim::CMC_Joint, OpenSim::CMC_Point, and OpenSim::SMC_Joint.

double CMC_Task::getAcceleration ( int aWhich ) const

Get the acceleration of a specified track goal.

The acceleration returned is the dot product of the appropriate track-goal direction and the acceleration of the point or orientation in question. In the case of generalized coordinates, the acceleration of the generalized coordinate is returned (i.e., a direction is not appropriate).

For the value returned by this method to be valid, the method computeAccelerations() must be called first.

Parameters:

aWhich

Specifies which track goal (0, 1, or 2).

Returns:: Acceleration. SimTK::NaN is returned on an error.

bool CMC_Task::getActive ( int aWhich ) const

Get whether a specified track goal is active.

Parameters:

aWhich

Number of the track goal in question.

Returns:: True if the specified track goal is active, false otherwise.

double CMC_Task::getDesiredAcceleration ( int aWhich ) const

Get the desired acceleration of a specified track goal.

The method computeDesiredAccelerations() must be called first for the values returned by this method to be valid.

Parameters:

aWhich

Specifies which track goal (0, 1, or 2).

Returns:: Desired acceleration. SimTK::NaN is returned on an error.

void CMC_Task::getDirection_0 ( SimTK::Vec3 & rR ) const

Get the direction of track goal 0.

Parameters:

aR

Direction.

void CMC_Task::getDirection_1 ( SimTK::Vec3 & rR ) const

Get the direction of track goal 1.

Parameters:

aR

Direction.

void CMC_Task::getDirection_2 ( SimTK::Vec3 & rR ) const

Get the direction of track goal 2.

Parameters:

aR

Direction.

std::string CMC_Task::getExpressBodyName ( ) const

Get the body in which the track goals are expressed.

Returns:: Body ID.

double CMC_Task::getKA ( int aWhich ) const

Get the acceleration gain for a specified track goal.

Parameters:

aWhich

Number of the track goal in question.

Returns:: Acceleration gain.

double CMC_Task::getKP ( int aWhich ) const

Get the position gain for a specified track goal.

Parameters:

aWhich

Number of the track goal in question.

Returns:: Position gain.

double CMC_Task::getKV ( int aWhich ) const

Get the velocity gain for a specified track goal.

Parameters:

aWhich

Number of the track goal in question.

Returns:: Velocity gain.

Model * CMC_Task::getModel ( ) const

Get the model to which this track object applies.

Returns:: Pointer to the model.

int CMC_Task::getNumTaskFunctions ( ) const

Get the number of position track functions.

Returns:: Number of position track functions.

bool CMC_Task::getOn ( ) const

Get whether or not this track object is on.

Returns:: True if on, false if off.

double CMC_Task::getPositionError ( int aWhich ) const

Get the position track error of a specified track goal.

Parameters:

aWhich

Specifies which track goal (0, 1, or 2).

Returns:: Error

double CMC_Task::getPositionErrorLast ( int aWhich ) const

Get the last achieved position error.

This information is useful for checking that error dynamics are being followed.

Parameters:

aWhich

Specifies which track goal (0, 1, or 2).

Returns:: Last position error.

double CMC_Task::getTaskAcceleration	(	int	aWhich,
		double	aT
	)			const

Get the task acceleration.

Parameters:

	aWhich	Specifies which task goal (0, 1, or 2).
	aT	Time (in real time units).

Returns:: Task acceleration.

Exceptions:

Exception

for an invalid task.

OpenSim::Function * CMC_Task::getTaskFunction ( int aWhich ) const

Get a specified track function.

Parameters:

aWhich

Specifies which track function (0, 1, or 2).

Returns:: Function.

OpenSim::Function * CMC_Task::getTaskFunctionForAcceleration ( int aWhich ) const

Get a specified acceleration track function.

Parameters:

aWhich

Specifies which track function (0, 1, or 2).

Returns:: Function.

OpenSim::Function * CMC_Task::getTaskFunctionForVelocity ( int aWhich ) const

Get a specified velocity track function.

Parameters:

aWhich

Specifies which track function (0, 1, or 2).

Returns:: Function.

double CMC_Task::getTaskPosition	(	int	aWhich,
		double	aT
	)			const

Get the task position.

Parameters:

	aWhich	Specifies which task goal (0, 1, or 2).
	aT	Time (in real time units).

Returns:: Task position.

Exceptions:

Exception

for an invalid task.

double CMC_Task::getTaskVelocity	(	int	aWhich,
		double	aT
	)			const

Get the task velocity.

Parameters:

	aWhich	Specifies which task goal (0, 1, or 2).
	aT	Time (in real time units).

Returns:: Task velocity.

Exceptions:

Exception

for an invalid task.

double CMC_Task::getVelocityError ( int aWhich ) const

Get the velocity track error of a specified track goal.

Parameters:

aWhich

Specifies which track goal (0, 1, or 2).

Returns:: Error

double CMC_Task::getVelocityErrorLast ( int aWhich ) const

Get the last achieved velocity error.

This information is useful for checking that error dynamics are being followed.

Parameters:

aWhich

Specifies which track goal (0, 1, or 2).

Returns:: Last velocity error.

double CMC_Task::getWeight ( int aWhich ) const

Get the weight of each track goal.

Parameters:

aWhich

Number of the track goal in question.

Returns:: Weight.

std::string CMC_Task::getWRTBodyName ( ) const

Get the body with respect to (WRT) which the track goals are specified.

Returns:: Body ID.

CMC_Task & CMC_Task::operator= ( const CMC_Task & aTask )

Assignment operator.

Returns:: Reference to the altered object.

Reimplemented from OpenSim::Object.

Reimplemented in OpenSim::CMC_Joint, OpenSim::CMC_Point, and OpenSim::SMC_Joint.

void CMC_Task::setActive	(	bool	a0,
		bool	a1 = `false`,
		bool	a2 = `false`
	)

Set whether or not track goals are active.

Parameters:

	a0	Active flag for track goal 0-- true means active.
	a1	Active flag for track goal 1-- true means active.
	a2	Active flag for track goal 2-- true means active.

void CMC_Task::setDirection_0 ( const SimTK::Vec3 & aR )

Set the direction of track goal 0.

Parameters:

aR

Direction. This vector is normalized.

void CMC_Task::setDirection_1 ( const SimTK::Vec3 & aR )

Set the direction of track goal 1.

Parameters:

aR

Direction. This vector is normalized.

void CMC_Task::setDirection_2 ( const SimTK::Vec3 & aR )

Set the direction of track goal 2.

Parameters:

aR

Direction. This vector is normalized.

void CMC_Task::setExpressBodyName ( std::string aBodyName )

Set the body in which the track goals are expressed.

Parameters:

aBody

Body ID.

void CMC_Task::setKA	(	double	aK0,
		double	aK1 = `0.0`,
		double	aK2 = `0.0`
	)

Set the acceleration gains for each track goal.

Parameters:

	aK0	Gain for track goal 0.
	aK1	Gain for track goal 1.
	aK2	Gain for track goal 2.

void CMC_Task::setKP	(	double	aK0,
		double	aK1 = `0.0`,
		double	aK2 = `0.0`
	)

Set the position gains for each track goal.

Parameters:

	aK0	Gain for track goal 0.
	aK1	Gain for track goal 1.
	aK2	Gain for track goal 2.

void CMC_Task::setKV	(	double	aK0,
		double	aK1 = `0.0`,
		double	aK2 = `0.0`
	)

Set the velocity gains for each track goal.

Parameters:

	aK0	Gain for track goal 0.
	aK1	Gain for track goal 1.
	aK2	Gain for track goal 2.

void CMC_Task::setModel ( Model & aModel ) [virtual]

Set the model to which this track object applies.

Parameters:

aModel

Model.

Reimplemented in OpenSim::CMC_Joint, and OpenSim::CMC_Point.

void CMC_Task::setOn ( bool aTrueFalse )

Turn this track object on or off.

Parameters:

aTureFalse

Turns analysis on if "true" and off if "false".

void CMC_Task::setPositionErrorLast	(	double	aE0,
		double	aE1 = `0.0`,
		double	aE2 = `0.0`
	)

Set the last achieved position error.

This information is useful for checking that error dynamics are being followed.

Parameters:

	aE0	Last position error for track goal 0.
	aE1	Last position error for track goal 1.
	aE2	Last position error for track goal 2.

void CMC_Task::setTaskFunctions	(	OpenSim::Function *	aF0,
		OpenSim::Function *	aF1 = `NULL`,
		OpenSim::Function *	aF2 = `NULL`
	)

Set the track functions.

Note that this method makes copies of the specified track functions, so the caller may use the specified functions for whatever purposes.

Parameters:

	aF0	Function for track goal 0.
	aF1	Function for track goal 1.
	aF2	Function for track goal 2.

void CMC_Task::setTaskFunctionsForAcceleration	(	OpenSim::Function *	aF0,
		OpenSim::Function *	aF1 = `NULL`,
		OpenSim::Function *	aF2 = `NULL`
	)

Set the acceleration track functions.

Note that this method makes copies of the specified track functions, so the caller may use the specified functions for whatever purposes.

Parameters:

	aF0	Function for track goal 0.
	aF1	Function for track goal 1.
	aF2	Function for track goal 2.

void CMC_Task::setTaskFunctionsForVelocity	(	OpenSim::Function *	aF0,
		OpenSim::Function *	aF1 = `NULL`,
		OpenSim::Function *	aF2 = `NULL`
	)

Set the velocity track functions.

Note that this method makes copies of the specified functions, so the caller may use the specified functions for whatever purposes.

Parameters:

	aF0	Function for track goal 0.
	aF1	Function for track goal 1.
	aF2	Function for track goal 2.

void CMC_Task::setVelocityErrorLast	(	double	aE0,
		double	aE1 = `0.0`,
		double	aE2 = `0.0`
	)

Set the last achieved velocity error.

This information is useful for checking that error dynamics are being followed.

Parameters:

	aE0	Last velocity error for track goal 0.
	aE1	Last velocity error for track goal 1.
	aE2	Last velocity error for track goal 2.

void CMC_Task::setWeight	(	double	aW0,
		double	aW1 = `0.0`,
		double	aW2 = `0.0`
	)

Set the weight of each track goal.

Parameters:

	aW0	Weight for track goal 0.
	aW1	Weight for track goal 1.
	aW2	Weight for track goal 2.

void CMC_Task::setWRTBodyName ( std::string aBodyName )

Set the body with respect to (WRT) which the track goals are specified.

Parameters:

aBody

Body ID.

void CMC_Task::updateFromXMLNode ( ) [virtual]

Update this object based on its XML node.

Reimplemented from OpenSim::Object.

Reimplemented in OpenSim::CMC_Joint, and OpenSim::CMC_Point.

Member Data Documentation

SimTK::Vec3 OpenSim::CMC_Task::_a [protected]

Accelerations.

Array<bool>& OpenSim::CMC_Task::_active [protected]

Reference to the value of the Active property.

SimTK::Vec3 OpenSim::CMC_Task::_aDes [protected]

Desired accelerations.

Function* OpenSim::CMC_Task::_aTrk[3] [protected]

Acceleration task functions.

If acceleration task functions are not specified, derivatives of the position task function are used.

std::string& OpenSim::CMC_Task::_expressBodyName [protected]

Reference to the value of the ExpressBody property.

double* OpenSim::CMC_Task::_j [protected]

Jacobian.

Array<double>& OpenSim::CMC_Task::_ka [protected]

Reference to the value of the KA property.

Array<double>& OpenSim::CMC_Task::_kp [protected]

Reference to the value of the KP property.

Array<double>& OpenSim::CMC_Task::_kv [protected]

Reference to the value of the KV property.

double* OpenSim::CMC_Task::_m [protected]

Effective mass matrix.

Model* OpenSim::CMC_Task::_model [protected]

Model.

int OpenSim::CMC_Task::_nTrk [protected]

Number of task functions.

bool& OpenSim::CMC_Task::_on [protected]

Reference to the value of the on property.

SimTK::Vec3 OpenSim::CMC_Task::_pErr [protected]

Position error.

SimTK::Vec3 OpenSim::CMC_Task::_pErrLast [protected]

Last position error.

PropertyBoolArray OpenSim::CMC_Task::_propActive [protected]

Property to specify the active task goals.

PropertyStr OpenSim::CMC_Task::_propExpressBodyName [protected]

Body frame in which the task goals are expressed.

PropertyDblArray OpenSim::CMC_Task::_propKA [protected]

Feedforward acceleration gain.

PropertyDblArray OpenSim::CMC_Task::_propKP [protected]

Position error feedback gain.

PropertyDblArray OpenSim::CMC_Task::_propKV [protected]

Velocity error feedback gain.

PropertyBool OpenSim::CMC_Task::_propOn [protected]

Property to indicate on or off state.

PropertyDblVec3 OpenSim::CMC_Task::_propR0 [protected]

Directions of the task goal 0.

PropertyDblVec3 OpenSim::CMC_Task::_propR1 [protected]

Directions of the task goal 1.

PropertyDblVec3 OpenSim::CMC_Task::_propR2 [protected]

Directions of the task goal 2.

PropertyDblArray OpenSim::CMC_Task::_propW [protected]

Weights of the task goals.

PropertyStr OpenSim::CMC_Task::_propWRTBodyName [protected]

Body with respect to which the task goals are specified.

Function* OpenSim::CMC_Task::_pTrk[3] [protected]

Position task functions.

Different types of tasks can require different numbers of task functions. For example, to track a joint angle, only one task function is needed. However, to track a position, up to three task functions may be needed.

SimTK::Vec3& OpenSim::CMC_Task::_r0 [protected]

Reference to the value of the R0 property.

SimTK::Vec3& OpenSim::CMC_Task::_r1 [protected]

Reference to the value of the R1 property.

SimTK::Vec3& OpenSim::CMC_Task::_r2 [protected]

Reference to the value of the R2 property.

SimTK::Vec3 OpenSim::CMC_Task::_vErr [protected]

Velocity error.

SimTK::Vec3 OpenSim::CMC_Task::_vErrLast [protected]

Last velocity error.

Function* OpenSim::CMC_Task::_vTrk[3] [protected]

Velocity task functions.