OpenSim::ForwardTool Class Reference

A concrete tool for perfroming forward dynamics simulations. More...

#include <ForwardTool.h>

Inheritance diagram for OpenSim::ForwardTool:

Public Member Functions
virtual	~ForwardTool ()
	Destructor.
	ForwardTool ()
	Default constructor.
	ForwardTool (const std::string &aFileName, bool aUpdateFromXMLNode=true, bool aLoadModel=true) SWIG_DECLARE_EXCEPTION
	ForwardTool (const ForwardTool &aObject)
	Copy constructor.
virtual Object *	copy () const
	Virtual copy constructor.
ForwardTool &	operator= (const ForwardTool &aForwardTool)
	Assignment operator.
virtual void	updateFromXMLNode ()
	Override default implementation by object to intercept and fix the XML node underneath the tool to match current version.
void	setManager (Manager &m)
	Set the current integration manager.
const Manager &	getManager () const
	Get the current integration manager.
const std::string &	getStatesFileName () const
void	setStatesFileName (const std::string &aFileName)
bool	getUseSpecifiedDt () const
void	setUseSpecifiedDt (bool aUseSpecifiedDt)
const std::string &	getExternalLoadsFileName () const
void	setExternalLoadsFileName (const std::string &aFileName)
const std::string &	getExternalLoadsModelKinematicsFileName () const
void	setExternalLoadsModelKinematicsFileName (const std::string &aFileName)
const std::string &	getExternalLoadsBody1 () const
void	setExternalLoadsBody1 (const std::string &aName)
const std::string &	getExternalLoadsBody2 () const
void	setExternalLoadsBody2 (const std::string &aName)
double	getLowpassCutoffFrequencyForLoadKinematics () const
void	setLowpassCutoffFrequencyForLoadKinematics (double aLowpassCutoffFrequency)
void	setPrintResultFiles (bool aToWrite)
virtual bool	run () SWIG_DECLARE_EXCEPTION
	Run the investigation.
void	printResults ()
void	loadStatesStorage (std::string &statesFileName, Storage *&rYStore) const
const std::string &	getParsingLog ()
Static Public Member Functions
static double	Step (double t, double t0, double t1)
	A smooth step-down function using cubic polynomial.
static double	SigmaUp (double tau, double to, double t)
	A smooth step-up function using exponentials.
static double	SigmaDn (double tau, double to, double t)
	A smooth step-down function using exponentials.
Protected Member Functions
void	setDesiredStatesForControllers (Storage &rYStore)
int	determineInitialTimeFromStatesStorage (double &rTI)
	Determine initial time for a simulation and find the index into the states storage for that time.
void	InitializeSpecifiedTimeStepping (Storage *aYStore, Manager &aManager)
	Setup time stepping so that the integrator follows a pre-specified series of time steps.
void	addCorrectiveSprings (SimTK::State &s, const Storage aYStore, const PrescribedForce aBody1Force, const PrescribedForce *aBody2Force)
	Add corrective springs.
LinearSpring *	addLinearCorrectiveSpring (SimTK::State &s, const Storage &aQStore, const Storage &aUStore, const PrescribedForce &aAppliedForce)
	Add a linear corrective spring.
TorsionalSpring *	addTorsionalCorrectiveSpring (SimTK::State &s, const Storage &aQStore, const Storage &aUStore, Body *aBody, double aTauOn, double aTimeOn, double aTauOff, double aTimeOff)
	Add a torsional corrective spring.
Protected Attributes
PropertyStr	_statesFileNameProp
	Name of the states file.
std::string &	_statesFileName
OpenSim::PropertyBool	_useSpecifiedDtProp
	If true, the time steps from the states file are used during current integration.
bool &	_useSpecifiedDt
OpenSim::PropertyStr	_externalLoadsFileNameProp
	Name of the file containing the external loads applied to the model.
std::string &	_externalLoadsFileName
OpenSim::PropertyStr	_externalLoadsModelKinematicsFileNameProp
	Name of the file containing the model kinematics corresponding to the external loads.
std::string &	_externalLoadsModelKinematicsFileName
OpenSim::PropertyStr	_externalLoadsBody1Prop
	Name of the body to which the first set of external loads should be applied (e.g., the body name for the right foot).
std::string &	_externalLoadsBody1
OpenSim::PropertyStr	_externalLoadsBody2Prop
	Name of the body to which the second set of external loads should be applied (e.g., the body name for the left foot).
std::string &	_externalLoadsBody2
OpenSim::PropertyDbl	_lowpassCutoffFrequencyForLoadKinematicsProp
	Low-pass cut-off frequency for filtering the model kinematics corresponding to the external loads.
double &	_lowpassCutoffFrequencyForLoadKinematics
OpenSim::PropertyBool	_outputDetailedResultsProp
	Flag indicating whether or not to output corrective spring loads and other quantities.
bool &	_outputDetailedResults
OpenSim::PropertyBool	_body1LinSpringActiveProp
	Flag indicating whether or not to turn on a linear corrective spring for the right foot.
bool &	_body1LinSpringActive
OpenSim::PropertyBool	_body1TorSpringActiveProp
	Flag indicating whether or not to turn on a torsional corrective spring for the right foot.
bool &	_body1TorSpringActive
OpenSim::PropertyBool	_body2LinSpringActiveProp
	Flag indicating whether or not to turn on a linear corrective spring for the left foot.
bool &	_body2LinSpringActive
OpenSim::PropertyBool	_body2TorSpringActiveProp
	Flag indicating whether or not to turn on a torsional corrective spring for the left foot.
bool &	_body2TorSpringActive
PropertyDbl	_body1TorSpringTimeOnProp
	Time at which the torsional spring comes on for body1 (if the spring is active).
double &	_body1TorSpringTimeOn
PropertyDbl	_body1TorSpringTimeOffProp
	Time at which the torsional spring turns off for body1 (if the spring is active).
double &	_body1TorSpringTimeOff
PropertyDbl	_body2TorSpringTimeOnProp
	Time at which the torsional spring turns on for body2 (if the spring is active).
double &	_body2TorSpringTimeOn
PropertyDbl	_body2TorSpringTimeOffProp
	Time at which the torsional spring turns off for body2 (if the spring is active).
double &	_body2TorSpringTimeOff
PropertyDbl	_tauProp
	Rise time for scaling functions for the torsional corrective springs.
double &	_tau
PropertyDbl	_tauBody1OnProp
	Scaling rise-time for the body1 torsional spring turning on.
double &	_tauBody1On
PropertyDbl	_tauBody1OffProp
	Scaling rise-time for the body1 torsional spring turning off.
double &	_tauBody1Off
PropertyDbl	_tauBody2OnProp
	Scaling rise-time for the body2 torsional spring turning on.
double &	_tauBody2On
PropertyDbl	_tauBody2OffProp
	Scaling rise-time for the body2 torsional spring turning off.
double &	_tauBody2Off
PropertyDbl	_springTransitionStartForceProp
	Force magnitude above which the linear springs start to scale in to effect.
double &	_springTransitionStartForce
PropertyDbl	_springTransitionEndForceProp
	Force magnitude below which the linear springs start to scale out of effect.
double &	_springTransitionEndForce
PropertyDbl	_forceThresholdProp
	Force magnitude below which no corrective linear spring forces are applied.
double &	_forceThreshold
PropertyDbl	_torqueThresholdProp
	Torque mangnitude below which no corrective torsional spring foreces are applied.
double &	_torqueThreshold
PropertyDblVec3	_kLinProp
	Stiffness for linear corrective springs.
SimTK::Vec3 &	_kLin
PropertyDblVec3	_bLinProp
	Damping for linear corrective springs.
SimTK::Vec3 &	_bLin
PropertyDblVec3	_kTorProp
	Stiffness for torsional corrective springs.
SimTK::Vec3 &	_kTor
PropertyDblVec3	_bTorProp
	Damping for torsional corrective springs.
SimTK::Vec3 &	_bTor
LinearSpring *	_body1Lin
	Pointer to the linear and torsional corrective springs.
LinearSpring *	_body2Lin
TorsionalSpring *	_body1Tor
TorsionalSpring *	_body2Tor
Storage *	_yStore
	Storage for the input states.
bool	_printResultFiles
	Flag indicating whether or not to write to the results (GUI will set this to false).
Manager *	_manager
	pointer to the simulation Manager
std::string	_parsingLog

Detailed Description

A concrete tool for perfroming forward dynamics simulations.

Author:: Frank C. Anderson

Version:: 1.0

Constructor & Destructor Documentation

ForwardTool::~ForwardTool ( ) [virtual]

Destructor.

ForwardTool::ForwardTool ( )

Default constructor.

OpenSim::ForwardTool::ForwardTool	(	const std::string &	aFileName,
		bool	aUpdateFromXMLNode = `true`,
		bool	aLoadModel = `true`
	)

ForwardTool::ForwardTool ( const ForwardTool & aTool )

Copy constructor.

Copy constructors for all Tools only copy the non-XML variable members of the object; that is, the object's DOMnode and XMLDocument are not copied but set to NULL. The reason for this is that for the object and all its derived classes to establish the correct connection to the XML document nodes, the the object would need to reconstruct based on the XML document not the values of the object's member variables.

There are three proper ways to generate an XML document for an Tool:

1) Construction based on XML file (

See also:: Tool(const char *aFileName)). In this case, the XML document is created by parsing the XML file.

2) Construction by Tool(const XMLDocument *aDocument). This constructor explictly requests construction based on an XML document. In this way the proper connection between an object's node and the corresponding node within the XML document is established. This constructor is a copy constructor of sorts because all essential Tool member variables should be held within the XML document. The advantage of this style of construction is that nodes within the XML document, such as comments that may not have any associated Tool member variable, are preserved.

3) A call to generateXMLDocument(). This method generates an XML document for the Tool from scratch. Only the essential document nodes are created (that is, nodes that correspond directly to member variables.).

Parameters:

aTool

Object to be copied.

See also:: Tool(const XMLDocument *aDocument); Tool(const char *aFileName); generateXMLDocument()

Member Function Documentation

void ForwardTool::addCorrectiveSprings	(	SimTK::State &	s,
		const Storage *	aYStore,
		const PrescribedForce *	aBody1Force,
		const PrescribedForce *	aBody2Force
	)			`[protected]`

Add corrective springs.

LinearSpring * ForwardTool::addLinearCorrectiveSpring	(	SimTK::State &	s,
		const Storage &	aQStore,
		const Storage &	aUStore,
		const PrescribedForce &	aAppliedForce
	)			`[protected]`

Add a linear corrective spring.

TorsionalSpring * ForwardTool::addTorsionalCorrectiveSpring	(	SimTK::State &	s,
		const Storage &	aQStore,
		const Storage &	aUStore,
		OpenSim::Body *	aBody,
		double	aTauOn,
		double	aTimeOn,
		double	aTauOff,
		double	aTimeOff
	)			`[protected]`

Add a torsional corrective spring.

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

Virtual copy constructor.

Reimplemented from OpenSim::Object.

Reimplemented in OpenSim::PerturbationTool.

int ForwardTool::determineInitialTimeFromStatesStorage ( double & rTI ) [protected]

Determine initial time for a simulation and find the index into the states storage for that time.

Parameters:

rTI

Requested initial time for the simulation. If the time does not match a time in the states storage exactly, the initial time is altered so that there is an exact match.

Returns:: Index into the states storage corresponding to the initial states for the simulation. A return of -1 indicates no valid states.

const std::string& OpenSim::ForwardTool::getExternalLoadsBody1 ( ) const [inline]

const std::string& OpenSim::ForwardTool::getExternalLoadsBody2 ( ) const [inline]

const std::string& OpenSim::ForwardTool::getExternalLoadsFileName ( ) const [inline]

const std::string& OpenSim::ForwardTool::getExternalLoadsModelKinematicsFileName ( ) const [inline]

double OpenSim::ForwardTool::getLowpassCutoffFrequencyForLoadKinematics ( ) const [inline]

const Manager & ForwardTool::getManager ( ) const

Get the current integration manager.

const std::string& OpenSim::ForwardTool::getParsingLog ( ) [inline]

const std::string& OpenSim::ForwardTool::getStatesFileName ( ) const [inline]

bool OpenSim::ForwardTool::getUseSpecifiedDt ( ) const [inline]

void ForwardTool::InitializeSpecifiedTimeStepping	(	Storage *	aYStore,
		Manager &	aManager
	)			`[protected]`

Setup time stepping so that the integrator follows a pre-specified series of time steps.

void ForwardTool::loadStatesStorage	(	std::string &	statesFileName,
		Storage *&	rYStore
	)			const

ForwardTool & ForwardTool::operator= ( const ForwardTool & aTool )

Assignment operator.

Returns:: Reference to this object.

Reimplemented from OpenSim::AbstractTool.

Reimplemented in OpenSim::PerturbationTool.

void ForwardTool::printResults ( )

bool ForwardTool::run ( ) [virtual]

Run the investigation.

Implements OpenSim::AbstractTool.

Reimplemented in OpenSim::PerturbationTool.

void OpenSim::ForwardTool::setDesiredStatesForControllers ( Storage & rYStore ) [protected]

void OpenSim::ForwardTool::setExternalLoadsBody1 ( const std::string & aName ) [inline]

void OpenSim::ForwardTool::setExternalLoadsBody2 ( const std::string & aName ) [inline]

void OpenSim::ForwardTool::setExternalLoadsFileName ( const std::string & aFileName ) [inline]

void OpenSim::ForwardTool::setExternalLoadsModelKinematicsFileName ( const std::string & aFileName ) [inline]

void OpenSim::ForwardTool::setLowpassCutoffFrequencyForLoadKinematics ( double aLowpassCutoffFrequency ) [inline]

void ForwardTool::setManager ( Manager & m )

Set the current integration manager.

Parameters:

m

pointer to itegration manager

void OpenSim::ForwardTool::setPrintResultFiles ( bool aToWrite ) [inline]

void OpenSim::ForwardTool::setStatesFileName ( const std::string & aFileName ) [inline]

void OpenSim::ForwardTool::setUseSpecifiedDt ( bool aUseSpecifiedDt ) [inline]

double ForwardTool::SigmaDn	(	double	tau,
		double	to,
		double	t
	)			`[static]`

A smooth step-down function using exponentials.

Parameters:

	tau	Rise and fall time constant.
	to	Location of the midpoint of the step.
	t	Independent variable

double ForwardTool::SigmaUp	(	double	tau,
		double	to,
		double	t
	)			`[static]`

A smooth step-up function using exponentials.

Parameters:

	tau	Rise and fall time constant.
	to	Location of the midpoint of the step.
	t	Independent variable

double ForwardTool::Step	(	double	t,
		double	t0,
		double	t1
	)			`[static]`

A smooth step-down function using cubic polynomial.

x=0 for t<t0, x=1 for t>t1, and x=smooth step in between t0 and t1.

Parameters:

	t	Parameter at which to evaluate step function
	t0	Parameter value at which step starts (result=0 to the left)
	t1	Parameter value at which step ends (result=1 to the right)

void ForwardTool::updateFromXMLNode ( ) [virtual]

Override default implementation by object to intercept and fix the XML node underneath the tool to match current version.

Reimplemented from OpenSim::AbstractTool.

Reimplemented in OpenSim::PerturbationTool.

Member Data Documentation

SimTK::Vec3& OpenSim::ForwardTool::_bLin [protected]

PropertyDblVec3 OpenSim::ForwardTool::_bLinProp [protected]

Damping for linear corrective springs.

LinearSpring* OpenSim::ForwardTool::_body1Lin [protected]

Pointer to the linear and torsional corrective springs.

bool& OpenSim::ForwardTool::_body1LinSpringActive [protected]

OpenSim::PropertyBool OpenSim::ForwardTool::_body1LinSpringActiveProp [protected]

Flag indicating whether or not to turn on a linear corrective spring for the right foot.

TorsionalSpring* OpenSim::ForwardTool::_body1Tor [protected]

bool& OpenSim::ForwardTool::_body1TorSpringActive [protected]

OpenSim::PropertyBool OpenSim::ForwardTool::_body1TorSpringActiveProp [protected]

Flag indicating whether or not to turn on a torsional corrective spring for the right foot.

double& OpenSim::ForwardTool::_body1TorSpringTimeOff [protected]

PropertyDbl OpenSim::ForwardTool::_body1TorSpringTimeOffProp [protected]

Time at which the torsional spring turns off for body1 (if the spring is active).

double& OpenSim::ForwardTool::_body1TorSpringTimeOn [protected]

PropertyDbl OpenSim::ForwardTool::_body1TorSpringTimeOnProp [protected]

Time at which the torsional spring comes on for body1 (if the spring is active).

LinearSpring * OpenSim::ForwardTool::_body2Lin [protected]

bool& OpenSim::ForwardTool::_body2LinSpringActive [protected]

OpenSim::PropertyBool OpenSim::ForwardTool::_body2LinSpringActiveProp [protected]

Flag indicating whether or not to turn on a linear corrective spring for the left foot.

TorsionalSpring * OpenSim::ForwardTool::_body2Tor [protected]

bool& OpenSim::ForwardTool::_body2TorSpringActive [protected]

OpenSim::PropertyBool OpenSim::ForwardTool::_body2TorSpringActiveProp [protected]

Flag indicating whether or not to turn on a torsional corrective spring for the left foot.

double& OpenSim::ForwardTool::_body2TorSpringTimeOff [protected]

PropertyDbl OpenSim::ForwardTool::_body2TorSpringTimeOffProp [protected]

Time at which the torsional spring turns off for body2 (if the spring is active).

double& OpenSim::ForwardTool::_body2TorSpringTimeOn [protected]

PropertyDbl OpenSim::ForwardTool::_body2TorSpringTimeOnProp [protected]

Time at which the torsional spring turns on for body2 (if the spring is active).

SimTK::Vec3& OpenSim::ForwardTool::_bTor [protected]

PropertyDblVec3 OpenSim::ForwardTool::_bTorProp [protected]

Damping for torsional corrective springs.

std::string& OpenSim::ForwardTool::_externalLoadsBody1 [protected]

OpenSim::PropertyStr OpenSim::ForwardTool::_externalLoadsBody1Prop [protected]

Name of the body to which the first set of external loads should be applied (e.g., the body name for the right foot).

std::string& OpenSim::ForwardTool::_externalLoadsBody2 [protected]

OpenSim::PropertyStr OpenSim::ForwardTool::_externalLoadsBody2Prop [protected]

Name of the body to which the second set of external loads should be applied (e.g., the body name for the left foot).

std::string& OpenSim::ForwardTool::_externalLoadsFileName [protected]

OpenSim::PropertyStr OpenSim::ForwardTool::_externalLoadsFileNameProp [protected]

Name of the file containing the external loads applied to the model.

std::string& OpenSim::ForwardTool::_externalLoadsModelKinematicsFileName [protected]

OpenSim::PropertyStr OpenSim::ForwardTool::_externalLoadsModelKinematicsFileNameProp [protected]

Name of the file containing the model kinematics corresponding to the external loads.

double& OpenSim::ForwardTool::_forceThreshold [protected]

PropertyDbl OpenSim::ForwardTool::_forceThresholdProp [protected]

Force magnitude below which no corrective linear spring forces are applied.

This allows an unperturbed forward integration to execute with minimal drift.

SimTK::Vec3& OpenSim::ForwardTool::_kLin [protected]

PropertyDblVec3 OpenSim::ForwardTool::_kLinProp [protected]

Stiffness for linear corrective springs.

SimTK::Vec3& OpenSim::ForwardTool::_kTor [protected]

PropertyDblVec3 OpenSim::ForwardTool::_kTorProp [protected]

Stiffness for torsional corrective springs.

double& OpenSim::ForwardTool::_lowpassCutoffFrequencyForLoadKinematics [protected]

OpenSim::PropertyDbl OpenSim::ForwardTool::_lowpassCutoffFrequencyForLoadKinematicsProp [protected]

Low-pass cut-off frequency for filtering the model kinematics corresponding to the external loads.

A negative value results in no filtering. The default value is -1.0, so no filtering.

Manager* OpenSim::ForwardTool::_manager [protected]

pointer to the simulation Manager

bool& OpenSim::ForwardTool::_outputDetailedResults [protected]

OpenSim::PropertyBool OpenSim::ForwardTool::_outputDetailedResultsProp [protected]

Flag indicating whether or not to output corrective spring loads and other quantities.

std::string OpenSim::ForwardTool::_parsingLog [protected]

bool OpenSim::ForwardTool::_printResultFiles [protected]

Flag indicating whether or not to write to the results (GUI will set this to false).

double& OpenSim::ForwardTool::_springTransitionEndForce [protected]

PropertyDbl OpenSim::ForwardTool::_springTransitionEndForceProp [protected]

Force magnitude below which the linear springs start to scale out of effect.

double& OpenSim::ForwardTool::_springTransitionStartForce [protected]

PropertyDbl OpenSim::ForwardTool::_springTransitionStartForceProp [protected]

Force magnitude above which the linear springs start to scale in to effect.

std::string& OpenSim::ForwardTool::_statesFileName [protected]

PropertyStr OpenSim::ForwardTool::_statesFileNameProp [protected]

Name of the states file.

The states file must at a minimum contain the initial states for a simulation. If a complete set of states is available, the time stamps can be used to specify the integration steps and corrective springs, which allow perturbations, can be added to the simulation.

double& OpenSim::ForwardTool::_tau [protected]

double& OpenSim::ForwardTool::_tauBody1Off [protected]

PropertyDbl OpenSim::ForwardTool::_tauBody1OffProp [protected]

Scaling rise-time for the body1 torsional spring turning off.

double& OpenSim::ForwardTool::_tauBody1On [protected]

PropertyDbl OpenSim::ForwardTool::_tauBody1OnProp [protected]

Scaling rise-time for the body1 torsional spring turning on.

double& OpenSim::ForwardTool::_tauBody2Off [protected]

PropertyDbl OpenSim::ForwardTool::_tauBody2OffProp [protected]

Scaling rise-time for the body2 torsional spring turning off.

double& OpenSim::ForwardTool::_tauBody2On [protected]

PropertyDbl OpenSim::ForwardTool::_tauBody2OnProp [protected]