OpenSim::JointReaction Class Reference

An analysis for reporting the joint reaction loads from a model. More...

#include <JointReaction.h>

Inheritance diagram for OpenSim::JointReaction:

Classes
struct	JointReactionKey
Public Member Functions
virtual	~JointReaction ()
	Destructor.
	JointReaction (Model *aModel=0)
	Construct a JointReaction instance.
	JointReaction (const std::string &aFileName)
	Construct an object from file.
	JointReaction (const JointReaction &aObject)
	Copy constructor.
virtual Object *	copy () const
	Clone.
JointReaction &	operator= (const JointReaction &aJointReaction)
	Assign this object to the values of another.
virtual void	setModel (Model &aModel)
	Set the model for which this analysis is to be run.
virtual int	begin (const SimTK::State &s)
	This method is called at the beginning of an analysis so that any necessary initializations may be performed.
virtual int	step (const SimTK::State &s)
	This method is called to perform the analysis.
virtual int	end (const SimTK::State &s)
	This method is called at the end of an analysis so that any necessary finalizations may be performed.
virtual int	printResults (const std::string &aBaseName, const std::string &aDir="", double aDT=-1.0, const std::string &aExtension=".sto")
	Print the results of the analysis.
Protected Member Functions
int	record (const SimTK::State &s)
	Compute and record the results.
void	setupReactionList ()
	Setup the ReactionList which controls the joints included in the analysis, the bodies the loads are applied to, and the frames the loads are expressed in.
void	constructDescription ()
	Construct a description for the joint reaction loads files.
void	constructColumnLabels ()
	Construct column labels for the output results.
void	setupStorage ()
	Set up storage objects.
void	loadForcesFromFile ()
	Load actuation storage from file.
Protected Attributes
PropertyStr	_forcesFileNameProp
	String containing the name of the optional forces storage file.
std::string &	_forcesFileName
PropertyStrArray	_jointNamesProp
	String Array containting the names of the joints to be analysed.
Array< std::string > &	_jointNames
PropertyStrArray	_onBodyProp
	String Array indicating which body of a joint (parent or child) the reaction load is applied to.
Array< std::string > &	_onBody
PropertyStrArray	_inFrameProp
	String Array indicating which frame (ground, parent child) the reaction load is expressed in.
Array< std::string > &	_inFrame
Storage *	_storeActuation
	Storage for holding actuator forces IF SPECIFIED by user.
Storage	_storeReactionLoads
	Storage for recording joint Reaction loads.
Array< double >	_dydt
	Internal work array for holding the computed accelerations.
Array< double >	_allLoads
	Internal work array for holding the computed joint loads for all joints in the model.
Array< double >	_Loads
	Internal work array for holding the computed joint loads of all joints specified in _jointNames.
Array< JointReactionKey >	_reactionList
	Internal work array for holding the JointReactionKeys to identify the desired joints, onBody, and inFrame to be output.
bool	_useForceStorage

Detailed Description

An analysis for reporting the joint reaction loads from a model.

For a given joint, the reaction load is calculated as the forces and moments required to constrain the body motions to satisfy the joint as if the joint did not exist. The reaction load acts at the joint center (mobilizer frame) of both the parent and child bodies and either force can be reported and expressed in the either the child, parent or ground frames. The default behavior is the the force on the child expressed in the ground frame.

Author:: Matt DeMers, Ajay Seth, Frank C. Anderson

Version:: 1.0

Constructor & Destructor Documentation

JointReaction::~JointReaction ( ) [virtual]

Destructor.

Delete any variables allocated using the "new" operator. You will not necessarily have any of these.

JointReaction::JointReaction ( Model * aModel = 0 )

Construct a JointReaction instance.

Parameters:

aModel

Model for which the analysis is to be run.

JointReaction::JointReaction ( const std::string & aFileName )

Construct an object from file.

The object is constructed from the root element of the XML document. The type of object is the tag name of the XML root element.

Parameters:

aFileName

File name of the document.

JointReaction::JointReaction ( const JointReaction & aObject )

Copy constructor.

Member Function Documentation

int JointReaction::begin ( const SimTK::State & s ) [virtual]

This method is called at the beginning of an analysis so that any necessary initializations may be performed.

This method is meant to be called at the begining of an integration

Parameters:

s

reference to the current state

Returns:: -1 on error, 0 otherwise.

Reimplemented from OpenSim::Analysis.

void JointReaction::constructColumnLabels ( ) [protected]

Construct column labels for the output results.

For analyses that run during a simulation, the first column is almost always time. For the purpose of example, the code below adds labels appropriate for recording the translation and orientation of each body in the model.

This method needs to be called as necessary to update the column labels.

void JointReaction::constructDescription ( ) [protected]

Construct a description for the joint reaction loads files.

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

Clone.

Reimplemented from OpenSim::Analysis.

int JointReaction::end ( const SimTK::State & s ) [virtual]

This method is called at the end of an analysis so that any necessary finalizations may be performed.

Parameters:

s

reference to the current state

Returns:: -1 on error, 0 otherwise.

Reimplemented from OpenSim::Analysis.

void JointReaction::loadForcesFromFile ( ) [protected]

Load actuation storage from file.

If called, this method sets _storeActuation to the forces data in _forcesFileName

JointReaction & JointReaction::operator= ( const JointReaction & aJointReaction )

Assign this object to the values of another.

Returns:: Reference to this object.

Reimplemented from OpenSim::Analysis.

virtual int OpenSim::JointReaction::printResults	(	const std::string &	aBaseName,
		const std::string &	aDir = `""`,
		double	aDT = `-1.0`,
		const std::string &	aExtension = `".sto"`
	)			`[virtual]`

Print the results of the analysis.

Parameters:

	aFileName	File to which to print the data.
	aDT	Time interval between results (linear interpolation is used). If not included as an argument or negative, all time steps are printed without interpolation.

Returns:: -1 on error, 0 otherwise.

Reimplemented from OpenSim::Analysis.

int JointReaction::record ( const SimTK::State & s ) [protected]

Compute and record the results.

This method computes the reaction loads at all joints in the model, then truncates the results to contain only the loads at the requested joints and finally, if necessary, modifies the loads to be acting on the specified body and expressed in the specified frame

Parameters:

	aT	Current time in the simulation.
	aX	Current values of the controls.
	aY	Current values of the states.

if a forces file is specified replace the computed actuation with the /** forces from storage.

define 2 variable length vectors of Vec3 vectors to contain calculated forces and moments for all the bodies in the model

void JointReaction::setModel ( Model & aModel ) [virtual]

Set the model for which this analysis is to be run.

Sometimes the model on which an analysis should be run is not available at the time an analysis is created. Or, you might want to change the model. This method is used to set the model on which the analysis is to be run.

Parameters:

aModel

Model pointer

Reimplemented from OpenSim::Analysis.

void JointReaction::setupReactionList ( ) [protected]

Setup the ReactionList which controls the joints included in the analysis, the bodies the loads are applied to, and the frames the loads are expressed in.

void JointReaction::setupStorage ( ) [protected]

Set up storage objects.

The storage objects in the analysis are used to record the results of the analysis and write them to file.

int JointReaction::step ( const SimTK::State & s ) [virtual]

This method is called to perform the analysis.

It can be called during the execution of a forward integrations or after the integration by feeding it the necessary data.

Parameters:

s

reference to the current stateaClientData General use pointer for sending in client data.

Returns:: -1 on error, 0 otherwise.

Reimplemented from OpenSim::Analysis.

Member Data Documentation

Array<double> OpenSim::JointReaction::_allLoads [protected]

Internal work array for holding the computed joint loads for all joints in the model.

Array<double> OpenSim::JointReaction::_dydt [protected]

Internal work array for holding the computed accelerations.

std::string& OpenSim::JointReaction::_forcesFileName [protected]

PropertyStr OpenSim::JointReaction::_forcesFileNameProp [protected]

String containing the name of the optional forces storage file.

Array<std::string>& OpenSim::JointReaction::_inFrame [protected]

PropertyStrArray OpenSim::JointReaction::_inFrameProp [protected]

String Array indicating which frame (ground, parent child) the reaction load is expressed in.

Array<std::string>& OpenSim::JointReaction::_jointNames [protected]

PropertyStrArray OpenSim::JointReaction::_jointNamesProp [protected]

String Array containting the names of the joints to be analysed.

Array<double> OpenSim::JointReaction::_Loads [protected]

Internal work array for holding the computed joint loads of all joints specified in _jointNames.

Array<std::string>& OpenSim::JointReaction::_onBody [protected]

PropertyStrArray OpenSim::JointReaction::_onBodyProp [protected]

String Array indicating which body of a joint (parent or child) the reaction load is applied to.

Array<JointReactionKey> OpenSim::JointReaction::_reactionList [protected]

Internal work array for holding the JointReactionKeys to identify the desired joints, onBody, and inFrame to be output.

Storage* OpenSim::JointReaction::_storeActuation [protected]

Storage for holding actuator forces IF SPECIFIED by user.

Storage OpenSim::JointReaction::_storeReactionLoads [protected]

Storage for recording joint Reaction loads.

bool OpenSim::JointReaction::_useForceStorage [protected]

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

OpenSim/Analyses/JointReaction.h
OpenSim/Analyses/JointReaction.cpp

OpenSim::JointReaction Class Reference

Classes

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation