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suSpringGeneralizedForce Class Reference

An actuator that exerts a generalized force based on spring-like characteristics (stiffness and viscosity). More...

#include <suSpringGeneralizedForce.h>

Inheritance diagram for suSpringGeneralizedForce:

List of all members.

Public Member Functions
	suSpringGeneralizedForce (int aQID=-1, int aNX=1, int aNY=0, int aNYP=0)
	Default constructor.
	suSpringGeneralizedForce (IDOM_Element *aElement, int aNX=1, int aNY=0, int aNYP=0)
	Construct the actuator from an XML Element.
	suSpringGeneralizedForce (const suSpringGeneralizedForce &aActuator)
	Copy constructor.
virtual	~suSpringGeneralizedForce ()
	Destructor.
virtual rdActuator *	copy () const
	Copy this actuator and return a pointer to the copy.
virtual rdActuator *	copy (IDOM_Element *aElement) const
	Copy this actuator and modify the copy so that it is consistent with a specified XML element node.
suSpringGeneralizedForce &	operator= (const suSpringGeneralizedForce &aActuator)
	Assignment operator.
virtual void	setControls (const double aX[])
	Set the controls.
virtual void	getControls (double rX[]) const
	Get the controls.
void	setRestLength (double aRestLength)
	Set the rest length of the actuator.
double	getRestLength () const
	Get the rest length of the actuator.
void	setViscosity (double aViscosity)
	Set the viscosity of the actuator.
double	getViscosity () const
	Get the viscosity of the actuator.
void	setStiffness (double aStiffness)
	Set the stiffness of the actuator.
double	getStiffness () const
	Get the stiffness of the actuator.
virtual void	computeActuation ()
	Compute all quantities necessary for applying the actuator force to the model.
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.
Protected Attributes
double	_restLength
	Rest length.
double	_viscosity
	Viscosity.
double	_stiffness
	Stiffness (control 0).
Private Member Functions
void	setNull ()
	Set the data members of this actuator to their null values.
Static Private Attributes
const char	PROP_REST_LENGTH [] = "rest_length"
const char	PROP_VISCOSITY [] = "viscosity"

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Detailed Description

An actuator that exerts a generalized force based on spring-like characteristics (stiffness and viscosity).

It has one control: stiffness.

Author:

Frank C. Anderson

Version:

1.0

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Constructor & Destructor Documentation

suSpringGeneralizedForce::suSpringGeneralizedForce (  IDOM_Element *  aElement, int  aNX = 1, int  aNY = 0, int  aNYP = 0 )

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

suSpringGeneralizedForce::suSpringGeneralizedForce (  const suSpringGeneralizedForce &  aActuator  )

Copy constructor. Parameters: aActuator  Actuator to be copied.

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Member Function Documentation

rdActuator * suSpringGeneralizedForce::copy (  IDOM_Element *  aElement  )  const [virtual]

Copy this actuator and modify the copy so that it is consistent with a specified XML element node. The copy is constructed by first using rdG::rdForce(IDOM_Element*,int,int) in order to establish the relationship of the rdForce object with the XML node. Then, the assignment operator is used to set all data members of the copy to the values of this rdForce object. Finally, the data members of the copy are updated using rdForce::updateObject(). Parameters: aElement  XML element. Returns: Pointer to a copy of this actuator. Reimplemented from rdGeneralizedForce.

rdActuator * suSpringGeneralizedForce::copy (   )  const [virtual]

Copy this actuator and return a pointer to the copy. The copy constructor for this class is used. Returns: Pointer to a copy of this actuator. Reimplemented from rdGeneralizedForce.

void suSpringGeneralizedForce::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 rdGeneralizedForce.

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

Get the controls. This actuator has 1 control: its stiffness. Parameters: rX  Control array- should have a length of at least 1. Reimplemented from rdGeneralizedForce.

double suSpringGeneralizedForce::getRestLength (   )  const

Get the rest length of the actuator. Returns: Rest length of the actuator.

double suSpringGeneralizedForce::getStiffness (   )  const

Get the stiffness of the actuator. Returns: Stiffness of the actuator.

double suSpringGeneralizedForce::getViscosity (   )  const

Get the viscosity of the actuator. Returns: Stiffness of the actuator.

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

Assignment operator. Returns: Reference to the altered object.

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

Set the controls. This actuator has 1 control: its stiffness. Parameters: aX  Control array- should have a length of at least 1. Reimplemented from rdGeneralizedForce.

void suSpringGeneralizedForce::setRestLength (  double  aRestLength  )

Set the rest length of the actuator. Parameters: aRestLength  Rest length of the actuator.

void suSpringGeneralizedForce::setStiffness (  double  aStiffness  )

Set the stiffness of the actuator. Normally the stiffness is a positive quantity. Negative stiffnessess will result in an unstable system- the force will push away from the rest length instead of pulling toward it. Parameters: aStiffness  Stiffness of the actuator.

void suSpringGeneralizedForce::setViscosity (  double  aViscosity  )

Set the viscosity of the actuator. Normally the viscosity should be a positive number. Negative viscosities will put energy into the system rather than apply a damping force. Parameters: aViscosity  Viscosity of the actuator.

void suSpringGeneralizedForce::updateData (   )

Update the member data of this object based on its XML node. Member objects (children) are not updated. Reimplemented from rdGeneralizedForce.

void suSpringGeneralizedForce::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 rdGeneralizedForce.

void suSpringGeneralizedForce::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 rdGeneralizedForce.

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

• suSpringGeneralizedForce.h
• suSpringGeneralizedForce.cpp

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