OpenSim::PrescribedForce Class Reference

This applies a force and/or torque to a body which is fully specified as a function of time. More...

#include <PrescribedForce.h>

Inheritance diagram for OpenSim::PrescribedForce:

Public Member Functions
	PrescribedForce (const OpenSim::Body &body)
	Construct a PrescribedForce.
	PrescribedForce (const PrescribedForce &force)
	Copy constructor.
	~PrescribedForce ()
	Destructor.
virtual Object *	copy () const
	Copy this force and return a pointer to the copy.
void	setForceFunctions (Function forceX, Function forceY, Function *forceZ)
	Set the functions which specify the force to apply.
void	getForceFunctions (Function forceX, Function forceY, Function *forceZ) const
void	setPointFunctions (Function pointX, Function pointY, Function *pointZ)
	Set the functions which specify the point at which to apply the force.
void	getPointFunctions (Function &pointX, Function &pointY, Function *&pointZ) const
void	setTorqueFunctions (Function torqueX, Function torqueY, Function *torqueZ)
	Set the functions which specify the torque to apply.
void	getTorqueFunctions (Function torqueX, Function torqueY, Function *torqueZ) const
void	setFunctionsFromFile (std::string anExternalLoadsFileName)
	Setup the functions from a specific type of storage file.
bool	getForceIsInGlobalFrame () const
	Get whether the force and torque are specified in inertial coordinates or in the body's local coordinates.
void	setForceIsInGlobalFrame (bool isGlobal)
	Set whether the force and torque are specified in inertial coordinates or in the body's local coordinates.
bool	getPointIsInGlobalFrame () const
	Get whether the point is specified in inertial coordinates or in the body's local coordinates.
void	setPointIsInGlobalFrame (bool isGlobal)
	Set whether the point is specified in inertial coordinates or in the body's local coordinates.
const Body &	getBody () const
	Get the body that the prescribed force is acting upon.
SimTK::Vec3	getForceAtTime (double aTime) const
	Conevenince methods to access prescribed force functions.
SimTK::Vec3	getPointAtTime (double aTime) const
SimTK::Vec3	getTorqueAtTime (double aTime) const
virtual OpenSim::Array < std::string >	getRecordLabels () const
	Methods used for reporting.
virtual OpenSim::Array< double >	getRecordValues (const SimTK::State &state) const
	Given SimTK::State object extract all the values necessary to report forces, application location frame, etc.
Protected Member Functions
virtual void	computeForce (const SimTK::State &state) const
	Compute the force.

Detailed Description

This applies a force and/or torque to a body which is fully specified as a function of time.

It is defined by three sets of functions, all of which are optional:

Three functions that specify a force to apply as a function of time. If these functions are not provided, no force is applied.

Three functions that specify the point at which the force should be applied. The resulting torque is automatically calculated and applied. If these functions are not provided, the force is applied at the body's center of mass, and therefore produces no torque.

Three functions that specify a torque to apply. This is in addition to any torque resulting from the force. If these functions are not provided, no additional torque is applied.

Author:: Peter Eastman, Matt DeMers

Constructor & Destructor Documentation

PrescribedForce::PrescribedForce ( const OpenSim::Body & body )

Construct a PrescribedForce.

Default constructor.

By default, the force, torque, and point functions are all unspecified, meaning that it applies no force or torque. To specify them, call setForceFunctions(), setTorqueFunctions(), and setPointFunctions().

Parameters:

body

the body to apply the force to

PrescribedForce::PrescribedForce ( const PrescribedForce & force )

Copy constructor.

PrescribedForce::~PrescribedForce ( )

Destructor.

Member Function Documentation

void PrescribedForce::computeForce ( const SimTK::State & state ) const [protected, virtual]

Compute the force.

Implements OpenSim::CustomForce.

Object * PrescribedForce::copy ( ) const [virtual]

Copy this force and return a pointer to the copy.

The copy constructor for this class is used.

Returns:: Pointer to a copy of this force.

Reimplemented from OpenSim::Object.

const Body& OpenSim::PrescribedForce::getBody ( ) const [inline]

Get the body that the prescribed force is acting upon.

Vec3 PrescribedForce::getForceAtTime ( double aTime ) const

Conevenince methods to access prescribed force functions.

void PrescribedForce::getForceFunctions	(	Function *	forceX,
		Function *	forceY,
		Function *	forceZ
	)			const

bool PrescribedForce::getForceIsInGlobalFrame ( ) const

Get whether the force and torque are specified in inertial coordinates or in the body's local coordinates.

Vec3 PrescribedForce::getPointAtTime ( double aTime ) const

void PrescribedForce::getPointFunctions	(	Function *&	pointX,
		Function *&	pointY,
		Function *&	pointZ
	)			const

bool PrescribedForce::getPointIsInGlobalFrame ( ) const

Get whether the point is specified in inertial coordinates or in the body's local coordinates.

OpenSim::Array< std::string > PrescribedForce::getRecordLabels ( ) const [virtual]

Methods used for reporting.

Reimplemented from OpenSim::Force.

OpenSim::Array< double > PrescribedForce::getRecordValues ( const SimTK::State & state ) const [virtual]

Given SimTK::State object extract all the values necessary to report forces, application location frame, etc.

used in conjunction with getRecordLabels and should return same size Array

Reimplemented from OpenSim::Force.

Vec3 PrescribedForce::getTorqueAtTime ( double aTime ) const

void PrescribedForce::getTorqueFunctions	(	Function *	torqueX,
		Function *	torqueY,
		Function *	torqueZ
	)			const

void PrescribedForce::setForceFunctions	(	Function *	forceX,
		Function *	forceY,
		Function *	forceZ
	)

Set the functions which specify the force to apply.

By default the force is specified in inertial coordinates. This can be changed by calling setForceIsInGlobalFrame().

All of the Function objects should have been allocated on the heap with the "new" operator. This object takes over ownership of them, and will delete them when it is deleted itself.

Parameters:

	forceX	a function of time which calculates the X component of the force to apply
	forceY	a function of time which calculates the Y component of the force to apply
	forceZ	a function of time which calculates the Z component of the force to apply

void PrescribedForce::setForceIsInGlobalFrame ( bool isGlobal )

Set whether the force and torque are specified in inertial coordinates or in the body's local coordinates.

void PrescribedForce::setFunctionsFromFile ( std::string anExternalLoadsFileName )

Setup the functions from a specific type of storage file.

Parameters:

anExternalLoadsFileName

the name of a .mot or .sto file. The file must contain 10 data columns labeled time, torqueX, torqueY, torqueZ, forceX, forceY, forceZ, pointX, pointY, pointZ

void PrescribedForce::setPointFunctions	(	Function *	pointX,
		Function *	pointY,
		Function *	pointZ
	)

Set the functions which specify the point at which to apply the force.

By default the point is specified in the body's local coordinates. This can be changed by calling setPointIsInGlobalFrame().

All of the Function objects should have been allocated on the heap with the "new" operator. This object takes over ownership of them, and will delete them when it is deleted itself.

Parameters:

	pointX	a function of time which calculates the X coordinate of the point at which to apply the force
	pointY	a function of time which calculates the Y coordinate of the point at which to apply the force
	pointZ	a function of time which calculates the Z coordinate of the point at which to apply the force

void PrescribedForce::setPointIsInGlobalFrame ( bool isGlobal )

Set whether the point is specified in inertial coordinates or in the body's local coordinates.

void PrescribedForce::setTorqueFunctions	(	Function *	torqueX,
		Function *	torqueY,
		Function *	torqueZ
	)

Set the functions which specify the torque to apply.

By default the torque is specified in inertial coordinates. This can be changed by calling setForceIsInGlobalFrame().

All of the Function objects should have been allocated on the heap with the "new" operator. This object takes over ownership of them, and will delete them when it is deleted itself.

Parameters:

	torqueX	a function of time which calculates the X component of the torque to apply
	torqueY	a function of time which calculates the Y component of the torque to apply
	torqueZ	a function of time which calculates the Z component of the torque to apply

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

OpenSim/Simulation/Model/PrescribedForce.h
OpenSim/Simulation/Model/PrescribedForce.cpp

OpenSim::PrescribedForce Class Reference

Public Member Functions

Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation