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rdActuator Class Reference

An abstract class for representing an actuator (e.g., a torque motor, muscle, ...). More...

#include <rdActuator.h>

Inheritance diagram for rdActuator:

List of all members.

Public Member Functions
	rdActuator (int aNX, int aNY, int aNYP)
	Construct an actuator that has a specified number of controls, states, and pseudostates.
	rdActuator (int aNX, int aNY, int aNYP, IDOM_Element *aElement)
	Construct an actuator from an XML Element.
	rdActuator (const rdActuator &aActuator)
	Copy constructor.
virtual	~rdActuator ()
	Destructor.
virtual rdActuator *	copy () const=0
virtual rdActuator *	copy (IDOM_Element *aElement) const=0
rdActuator &	operator= (const rdActuator &aActuator)
	Assignment operator.
void	setModel (rdModel *aModel)
	Set the model which this actuator actuates.
rdModel *	getModel () const
	Get a pointer to the model on which this analysis is being performed.
int	getNX () const
	Get the number of controls.
const char *	getControlName (int aIndex) const
	Get the name of a control.
virtual void	setControls (const double aX[])
	Set the current values of the controls.
virtual void	getControls (double rX[]) const
	Get the current values of the controls.
int	getNY () const
	Get the number of states.
const char *	getStateName (int aIndex) const
	Get the name of a state.
virtual void	setStates (const double aY[])
	Set the current values of the states.
virtual void	getStates (double rY[]) const
	Get the current values of the states.
int	getNYP () const
	Get the number of pseudostates.
const char *	getPseudoStateName (int aIndex) const
	Get the name of a pseudostate.
virtual void	setPseudoStates (const double aY[])
	Set the current values of the pseudostates.
virtual void	getPseudoStates (double rY[]) const
	Get the current values of the pseudostates.
bool	getAppliesForce () const
	Get whether the actuator applies a force or torque to the model.
void	setForce (double aForce)
	Set the current force (or torque) of the actuator.
double	getForce () const
	Get the current force (or torque) of the actuator.
double	getSpeed () const
	Get the current speed (linear or angular) of the actuator.
double	getPower () const
	Get the instantaneous power developed by an actuator.
void	setMaxForce (double aMax)
	Set the maximum force (or torque) that can by applied by the actuator.
double	getMaxForce () const
	Get the maximum force (or torque) that can by applied by the actuator.
void	setMinForce (double aMin)
	Set the minimum force (or torque) that can by applied by the actuator.
double	getMinForce () const
	Get the minimum force (or torque) that can by applied by the actuator.
virtual void	promoteControlsToStates (const double aX[], double aDT)
	Promote a set of controls to state variables.
virtual void	computeActuation ()=0
virtual void	computeStateDerivatives (double rDYDT[])
	Compute the time derivatives of the states for this actuator.
virtual void	updatePseudoStates ()
	Update actuator parameters so they are intervally consistent.
virtual void	apply ()=0
virtual bool	check () const
	Check that this actuator is valid.
virtual void	updateObject (bool aDeep=true)
	Update this object based on its XML node.
virtual void	updateNode (bool aDeep=true)
	Update the XML node representing this object.
virtual void	generateNode (IDOM_Element *aParent)
	Generate an XML node representing this object.
void	updateData ()
	Update the member data of this object based on its XML node.
Static Public Attributes
const double	LARGE = 1.0e8
const int	NAME_LENGTH = rdObject_NAME_LENGTH
	A length limit for the name of an object.
const char	DEFAULT_NAME [] = "default"
const char	PROP_MAXFORCE [] = "max_force"
const char	PROP_MINFORCE [] = "min_force"
Protected Member Functions
void	setControlName (int aIndex, const char *aName)
	Set the name of a control.
void	setStateName (int aIndex, const char *aName)
	Set the name of a state.
void	setPseudoStateName (int aIndex, const char *aName)
	Set the name of a pseudostate.
Protected Attributes
rdModel *	_model
	Model which the actuator actuates.
int	_nx
	Number of controls that control this actuator.
char **	_xNames
	Names of the controls.
int	_ny
	Number of states that characterize this actuator.
char **	_yNames
	Names of the states.
int	_nyp
	Number of pseudostates in this actuator.
char **	_ypNames
	Names of the pseudostates.
bool	_appliesForce
	Flag indicating whether the actuator applies a force or a torque.
double	_force
	Force (or torque) magnitude that is applied to the model.
double	_speed
	Speed of actuator (linear or angular).
double	_maxForce
	Maximum force (or torque) that this actuator can apply.
double	_minForce
	Minimum force (or torque) that this actuator can apply.
Private Member Functions
void	setNull ()
	Set the data members of this actuator to their null values.
void	constructControls ()
	Construct controls.
void	constructStates ()
	Construct states.
void	constructPseudoStates ()
	Construct pseudostates.

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Detailed Description

An abstract class for representing an actuator (e.g., a torque motor, muscle, ...).

Author:

Frank C. Anderson

Version:

1.0

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Constructor & Destructor Documentation

rdActuator::rdActuator (  int  aNX, int  aNY, int  aNYP )

Construct an actuator that has a specified number of controls, states, and pseudostates. Parameters: aNX  Number of controls. aNY  Number of states. aNYP  Number of pseudostates.

rdActuator::rdActuator (  int  aNX, int  aNY, int  aNYP, IDOM_Element *  aElement )

Construct an actuator from an XML Element. Parameters: aNX  Number of controls. aNY  Number of states. aNYP  Number of pseudo-states. aElement  XML element.

rdActuator::rdActuator (  const rdActuator &  aActuator  )

Copy constructor. Parameters: aActuator  Actuator to copy.

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Member Function Documentation

void rdActuator::computeStateDerivatives (  double  rDYDT[]  )  [virtual]

Compute the time derivatives of the states for this actuator. This method should be overridden by derived classes that have actuator states. In rdActuator this method is empty and put here so that derived classes that don't have any actuator states won't have to implement this method. Parameters: rDYDT  Time derivatives of the states. Reimplemented in rdGeneralizedForceAtv, and rdMuscleZajac.

void rdActuator::generateNode (  IDOM_Element *  aParent  )  [virtual]

Generate an XML node representing this object. Parameters: aParent  Intended parent of the node to be generated. If aParent is NULL, the intent is for this object to serve as the root element of a new document. See also: rdObject::generateNode() Reimplemented from rdObject. Reimplemented in rdGeneralizedForceAtv, rdLinearSetPoint, rdMuscleZajac, rdPolynomialSetPoint, rdSetPoint, rdContactForce, rdForce, rdGeneralizedForce, and suSpringGeneralizedForce.

bool rdActuator::getAppliesForce (   )  const

Get whether the actuator applies a force or torque to the model. Returns: True if the actuator applies a force, false if the actuator applies a torque.

const char * rdActuator::getControlName (  int  aIndex  )  const

Get the name of a control. Parameters: aIndex  Index of the control whose name is desired.

void rdActuator::getControls (  double  rX[]  )  const [virtual]

Get the current values of the controls. Parameters: aX  Array of control values. Reimplemented in rdGeneralizedForceAtv, rdMuscleZajac, rdForce, rdGeneralizedForce, and suSpringGeneralizedForce.

double rdActuator::getForce (   )  const

Get the current force (or torque) of the actuator. The force (or torque) is represented as a scalar; its vector properties derive from the geometry characterizing how it is applied to the model. The particulars of the geometry is dependent on the type of the actuator. Returns: Force (or torque) of the actuator.

double rdActuator::getMaxForce (   )  const

Get the maximum force (or torque) that can by applied by the actuator. Returns: Maximum force or torque.

double rdActuator::getMinForce (   )  const

Get the minimum force (or torque) that can by applied by the actuator. Returns: Minimum force or torque.

rdModel * rdActuator::getModel (   )  const

Get a pointer to the model on which this analysis is being performed. Returns: Pointer to the model.

int rdActuator::getNX (   )  const

Get the number of controls. Returns: Number of controls.

int rdActuator::getNY (   )  const

Get the number of states. Returns: Number of states.

int rdActuator::getNYP (   )  const

Get the number of pseudostates. Returns: Number of pseudostates.

double rdActuator::getPower (   )  const

Get the instantaneous power developed by an actuator. The instantaneous power is the product of the actuator force and the actuator speed. If the power is positive, the actuator is delivering energy to the model. If the power is negative, the actuator is absorbing energy from the model. Returns: Instantaneous power of the actuator.

const char * rdActuator::getPseudoStateName (  int  aIndex  )  const

Get the name of a pseudostate. Parameters: aIndex  Index of the pseudostate whose name is desired.

void rdActuator::getPseudoStates (  double  rY[]  )  const [virtual]

Get the current values of the pseudostates. Parameters: rYP  Array of pseudostate values. Reimplemented in rdSetPoint.

double rdActuator::getSpeed (   )  const

Get the current speed (linear or angular) of the actuator. The speed is the dot product of the direction of force applied by the actuator to Body1 and the velocity of shortening of the actuator: speed = DotProduct(u1,v), where u1 = unit vector describing the direction of force applied to Body1 expressed in the Body0 frame. v = velocity of Point1 in the frame of Body0 expressed in the Body0 frame. Returns: Speed (or angular velocity) of the actuator.

const char * rdActuator::getStateName (  int  aIndex  )  const

Get the name of a state. Parameters: aIndex  Index of the state whose name is desired.

void rdActuator::getStates (  double  rY[]  )  const [virtual]

Get the current values of the states. Parameters: rYP  Array of state values. Reimplemented in rdGeneralizedForceAtv, and rdMuscleZajac.

rdActuator & rdActuator::operator= (  const rdActuator &  aActuator  )

Assignment operator. Returns: Reference to this object.

void rdActuator::promoteControlsToStates (  const double  aX[], double  aDT )  [virtual]

Promote a set of controls to state variables. This method is normally useful when solving for controls that will optimize some aspect of a model performance. For example, in models in which the controls are neural excitations, but muscle forces are determined by activation level, this method might set the muscle activations equal to the excitations. Each actuator is responsible for knowing how to promote its own controls to states. Reimplemented in rdGeneralizedForceAtv, and rdMuscleZajac.

void rdActuator::setControlName (  int  aIndex, const char *  aName )  [protected]

Set the name of a control. This method is protected and is to be used outside this class and its derived classes. Parameters: aIndex  Index of the control whose name is to be set. aName  Name.

void rdActuator::setControls (  const double  aX[]  )  [virtual]

Set the current values of the controls. Parameters: aX  Array of control values. Reimplemented in rdGeneralizedForceAtv, rdMuscleZajac, rdForce, rdGeneralizedForce, and suSpringGeneralizedForce.

void rdActuator::setForce (  double  aForce  )

Set the current force (or torque) of the actuator. The force (or torque) is represented as a scalar; its vector properties derive from the geometry characterizing how it is applied to the model. The particulars of the geometry is dependent on the type of the actuator. Note that this method clamps the force between the maximum and minimum force allowed for the actuator. Returns: Force (or torque) of the actuator. See also: rdActuator::setMaxForce rdActuator::setMinForce

void rdActuator::setMaxForce (  double  aMax  )

Set the maximum force (or torque) that can by applied by the actuator. Parameters: aMax  Maximum force or torque.

void rdActuator::setMinForce (  double  aMin  )

Set the minimum force (or torque) that can by applied by the actuator. Parameters: aMin  Minimum force or torque.

void rdActuator::setModel (  rdModel *  aModel  )

Set the model which this actuator actuates. Parameters: aModel  Pointer to a model.

void rdActuator::setPseudoStateName (  int  aIndex, const char *  aName )  [protected]

Set the name of a pseudostate. This method is protected and is not intended to be used outside this class and its derived classes. Parameters: aIndex  Index of the pseudostate whose name is to be set. aName  Name.

void rdActuator::setPseudoStates (  const double  aY[]  )  [virtual]

Set the current values of the pseudostates. Parameters: aYP  Array of pseudostate values. Reimplemented in rdSetPoint.

void rdActuator::setStateName (  int  aIndex, const char *  aName )  [protected]

Set the name of a state. This method is protected and is not intended to be used outside this class and its derived classes. Parameters: aIndex  Index of the state whose name is to be set. aName  Name.

void rdActuator::setStates (  const double  aY[]  )  [virtual]

Set the current values of the states. Parameters: aY  Array of state values. Reimplemented in rdGeneralizedForceAtv, and rdMuscleZajac.

void rdActuator::updateData (   )

Update the member data of this object based on its XML node. Member objects (children) are not updated. Reimplemented in rdGeneralizedForceAtv, rdLinearSetPoint, rdMuscleZajac, rdPolynomialSetPoint, rdSetPoint, rdContactForce, rdForce, rdGeneralizedForce, and suSpringGeneralizedForce.

void rdActuator::updateNode (  bool  aDeep = true  )  [virtual]

Update the XML node representing this object. Parameters: aDeep  If true, update the XML node of this object AND the XML nodes of all class members that are rdObjects (child nodes); if false, update only the XML node of this object without updating the XML nodes of its children. Reimplemented from rdObject. Reimplemented in rdGeneralizedForceAtv, rdLinearSetPoint, rdMuscleZajac, rdPolynomialSetPoint, rdSetPoint, rdContactForce, rdForce, rdGeneralizedForce, and suSpringGeneralizedForce.

void rdActuator::updateObject (  bool  aDeep = true  )  [virtual]

Update this object based on its XML node. Parameters: aDeep  If true, update this object and all its child objects (that is, member variables that are rdObject's); if false, update only the member variables that are not rdObject's. Reimplemented from rdObject. Reimplemented in rdGeneralizedForceAtv, rdLinearSetPoint, rdMuscleZajac, rdPolynomialSetPoint, rdSetPoint, rdContactForce, rdForce, rdGeneralizedForce, and suSpringGeneralizedForce.

void rdActuator::updatePseudoStates (   )  [virtual]

Update actuator parameters so they are intervally consistent. This method is distinguished from computeActuation() in that it is normally called only after an integration time step has been taken. Updating spring setpoints is an example. Reimplemented in rdSetPoint, and rdContactForce.

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Member Data Documentation

int rdActuator::_nyp [protected]

Number of pseudostates in this actuator. Pseudostates are variables that are not integrated but that depend on the history of the integration. They cannot be determined from the states.

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

• rdActuator.h
• rdActuator.cpp

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