OpenSim::Constraint Class Reference

A parent class for implementing a Simbody Constraint. More...

#include <Constraint.h>

Inheritance diagram for OpenSim::Constraint:

List of all members.

Public Member Functions
	Constraint ()
	Default constructor.
	Constraint (const Constraint &aConstraint)
	Copy constructor.
virtual	~Constraint ()
	Destructor.
virtual Object *	copy () const
	Copy this Constraint and return a pointer to the copy.
Constraint &	operator= (const Constraint &aConstraint)
	Assignment operator.
void	copyData (const Constraint &aConstraint)
	Copy data members from one Constraint to another.
virtual void	setup (Model &aModel)
	Perform some set up functions that happen after the object has been deserialized or copied.
virtual void	initState (SimTK::State &completeState) const
	This is called after a SimTK System and State have been created for the Model.
virtual void	setDefaultsFromState (const SimTK::State &state)
	Set all default values for this object to match those in a specified State.
virtual void	updateFromConstraint (SimTK::State &s, const Constraint &aConstraint)
	Update an existing Constraint with parameter values from a new one, but only for the parameters that were explicitly specified in the XML node.
virtual bool	getIsDisabled (const SimTK::State &s) const
	Get whether or not this Constraint is disabled.
virtual bool	setIsDisabled (SimTK::State &s, bool isDisabled) const
	Set whether or not this Constraint is disabled.
virtual void	calcConstraintForces (const SimTK::State &s, SimTK::Vector_< SimTK::SpatialVec > &bodyForcesInParent, SimTK::Vector &mobilityForces)
	Ask the constraint for the forces it is imposing on the system Simbody multibody system must be realized to at least position Returns: the bodyForces on those bodies being constrained (constrainedBodies) a SpatialVec (6 components) describing resulting torque and force mobilityForces acting along constrained mobilities.
virtual void	scale (const ScaleSet &aScaleSet)
Protected Attributes
PropertyBool	_isDisabledProp
	Flag indicating whether the constraint is disabled or not.
SimTK::ConstraintIndex	_index
	ID for the constraint in Simbody.
Friends
class	SimbodyEngine

---

Detailed Description

A parent class for implementing a Simbody Constraint.

Specific constraints should be derived from this class.

Author:

Frank C. Anderson

Ajay Seth

Version:

1.0

---

Constructor & Destructor Documentation

Constraint::Constraint

(

)

Default constructor.

Constraint::Constraint

(

const Constraint &

aConstraint

)

Copy constructor.

Parameters:

aConstraint

Constraint to be copied.

Constraint::~Constraint

(

)

[virtual]

Destructor.

---

Member Function Documentation

void Constraint::calcConstraintForces	(	const SimTK::State &	s,
		SimTK::Vector_< SimTK::SpatialVec > &	bodyForcesInParent,
		SimTK::Vector &	mobilityForces
	)			[virtual]

Ask the constraint for the forces it is imposing on the system Simbody multibody system must be realized to at least position Returns: the bodyForces on those bodies being constrained (constrainedBodies) a SpatialVec (6 components) describing resulting torque and force mobilityForces acting along constrained mobilities.

Parameters:

	state	State of model
	bodyForcesInParent	is a Vector of SpatialVecs contain constraint forces
	mobilityForces	is a Vector of forces that act along the constrained mobilitities associated with this constraint

Reimplemented in OpenSim::RollingOnSurfaceConstraint.

Object * Constraint::copy

(

)

const [virtual]

Copy this Constraint and return a pointer to the copy.

The copy constructor for this class is used.

Returns:

Pointer to a copy of this Constraint.

Reimplemented from OpenSim::Object.

Reimplemented in OpenSim::CoordinateCouplerConstraint, OpenSim::PointConstraint, OpenSim::PointOnLineConstraint, OpenSim::RollingOnSurfaceConstraint, OpenSim::UnilateralConstraint, and OpenSim::WeldConstraint.

void Constraint::copyData

(

const Constraint &

aConstraint

)

Copy data members from one Constraint to another.

Parameters:

aConstraint

Constraint to be copied.

Reimplemented in OpenSim::CoordinateCouplerConstraint, OpenSim::PointConstraint, OpenSim::PointOnLineConstraint, OpenSim::RollingOnSurfaceConstraint, OpenSim::UnilateralConstraint, and OpenSim::WeldConstraint.

bool Constraint::getIsDisabled

(

const SimTK::State &

s

)

const [virtual]

Get whether or not this Constraint is disabled.

Simbody multibody system instance is realized every time the isDisabled changes, BUT multiple sets to the same value have no cost.

Parameters:

isDisabled

If true the constraint is disabled; if false the constraint is enabled.

Reimplemented in OpenSim::RollingOnSurfaceConstraint.

void Constraint::initState

(

SimTK::State &

state

)

const [virtual]

This is called after a SimTK System and State have been created for the Model.

It may be overridden to set initial values of state variables.

Parameters:

state

the State to initialize

Reimplemented from OpenSim::ModelComponent.

Constraint & Constraint::operator=

(

const Constraint &

aConstraint

)

Assignment operator.

Returns:

Reference to this object.

Reimplemented from OpenSim::Object.

Reimplemented in OpenSim::CoordinateCouplerConstraint, OpenSim::PointConstraint, OpenSim::PointOnLineConstraint, OpenSim::RollingOnSurfaceConstraint, OpenSim::UnilateralConstraint, and OpenSim::WeldConstraint.

virtual void OpenSim::Constraint::scale

(

const ScaleSet &

aScaleSet

)

[inline, virtual]

Reimplemented in OpenSim::CoordinateCouplerConstraint.

void Constraint::setDefaultsFromState

(

const SimTK::State &

state

)

[virtual]

Set all default values for this object to match those in a specified State.

It should be overridden to set any default values defined by each subclass.

Parameters:

state

the State from which to take values that should become the defaults for this object

Reimplemented from OpenSim::ModelComponent.

bool Constraint::setIsDisabled	(	SimTK::State &	s,
		bool	isDisabled
	)			const [virtual]

Set whether or not this Constraint is disabled.

Simbody multibody system instance is realized every time the isDisabled changes, BUT multiple sets to the same value have no cost.

Parameters:

isDisabled

If true the constraint is disabled; if false the constraint is enabled.

void Constraint::setup

(

Model &

aModel

)

[virtual]

Perform some set up functions that happen after the object has been deserialized or copied.

Parameters:

aModel

OpenSim model containing this Constraint.

Reimplemented in OpenSim::CoordinateCouplerConstraint, OpenSim::PointOnLineConstraint, OpenSim::RollingOnSurfaceConstraint, OpenSim::UnilateralConstraint, and OpenSim::WeldConstraint.

void Constraint::updateFromConstraint	(	SimTK::State &	s,
		const Constraint &	aConstraint
	)			[virtual]

Update an existing Constraint with parameter values from a new one, but only for the parameters that were explicitly specified in the XML node.

Parameters:

aConstraint

Constraint to update from

---

Friends And Related Function Documentation

friend class SimbodyEngine [friend]

Reimplemented in OpenSim::CoordinateCouplerConstraint, OpenSim::PointConstraint, OpenSim::PointOnLineConstraint, OpenSim::RollingOnSurfaceConstraint, OpenSim::UnilateralConstraint, and OpenSim::WeldConstraint.

---

Member Data Documentation

SimTK::ConstraintIndex OpenSim::Constraint::_index [protected]

ID for the constraint in Simbody.

PropertyBool OpenSim::Constraint::_isDisabledProp [protected]

Flag indicating whether the constraint is disabled or not.

Disabled means that the constraint is not active in subsequent dynamics realizations.

---

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

• OpenSim/Simulation/SimbodyEngine/Constraint.h
• OpenSim/Simulation/SimbodyEngine/Constraint.cpp