The ClutchedPathSpring is an actuator that has passive path spring behavior only when the clutch is engaged. More...

#include <ClutchedPathSpring.h>

Inheritance diagram for OpenSim::ClutchedPathSpring:

Public Member Functions
	ClutchedPathSpring ()

	ClutchedPathSpring (const std::string &name, double stiffness, double dissipation, double relaxationTau, double stretch0=0.0)
	Convenience constructor with ClutchedPathSpring parameters. More...

double	getStiffness () const
	Spring stiffness in N/m when clutch is engaged. More...

void	setStiffness (double stiffness)

double	getDissipation () const
	Spring dissipation factor in s/m when clutch is engaged. More...

void	setDissipation (double dissipation)

double	getInitialStretch ()
	Initial spring stretch in m. More...

void	setInitialStretch (double stretch0)

double	getStretch (const SimTK::State &s) const
	The stretch in the PathSpring. More...

double	getTension (const SimTK::State &s) const
	The tension generated by the PathSpring. More...

Property declarations
These are the serializable properties of the ClutchedPathSpring class.
	OpenSim_DECLARE_PROPERTY (stiffness, double,"The linear stiffness (N/m) of the ClutchedPathSpring")

	OpenSim_DECLARE_PROPERTY (dissipation, double,"The dissipation factor (s/m) of the ClutchedPathSpring")

	OpenSim_DECLARE_PROPERTY (relaxation_time_constant, double,"The time constant (s) for the spring to relax (go slack) after the clutch ""is disengaged (i.e. control == 0). If the clutch is re-engaged within the ""relaxation period there will be residual tension in the spring.")

	OpenSim_DECLARE_PROPERTY (initial_stretch, double,"The initial stretch (m) of the spring element. Note if the clucth is ""not engaged, the actuator will 'slip' until there is no stretch according ""to the relaxation_time_constant.")

Public Member Functions inherited from OpenSim::PathActuator
	PathActuator ()

GeometryPath &	updGeometryPath ()

const GeometryPath &	getGeometryPath () const

virtual bool	hasGeometryPath () const
	Return a flag indicating whether the Force is applied along a Path. More...

void	setOptimalForce (double aOptimalForce)

double	getOptimalForce () const

virtual double	getLength (const SimTK::State &s) const

virtual double	getLengtheningSpeed (const SimTK::State &s) const

virtual double	getPower (const SimTK::State &s) const

virtual double	getStress (const SimTK::State &s) const

void	addNewPathPoint (const std::string &proposedName, OpenSim::Body &aBody, const SimTK::Vec3 &aPositionOnBody)
	Note that this function does not maintain the State and so should be used only before a valid State is created. More...

virtual void	computeForce (const SimTK::State &state, SimTK::Vector_< SimTK::SpatialVec > &bodyForces, SimTK::Vector &mobilityForces) const
	Subclasses must implement this method to compute the forces that should be applied to bodies and generalized speeds. More...

virtual double	computeMomentArm (const SimTK::State &s, Coordinate &aCoord) const

virtual void	updateFromXMLNode (SimTK::Xml::Element &aNode, int versionNumber=-1)
	Use this method to deserialize an object from a SimTK::Xml::Element. More...

virtual void	preScale (const SimTK::State &s, const ScaleSet &aScaleSet)

virtual void	scale (const SimTK::State &s, const ScaleSet &aScaleSet)

virtual void	postScale (const SimTK::State &s, const ScaleSet &aScaleSet)

virtual const VisibleObject *	getDisplayer () const
	Methods to support making the object displayable in the GUI or Visualizer Implemented only in few objects. More...

virtual void	updateDisplayer (const SimTK::State &s) const
	In case the ModelComponent has a visual representation (VisualObject), override this method to update it. More...

	OpenSim_DECLARE_UNNAMED_PROPERTY (GeometryPath,"The set of points defining the path of the muscle.")

	OpenSim_DECLARE_PROPERTY (optimal_force, double,"The maximum force this actuator can produce.")

Public Member Functions inherited from OpenSim::Actuator
	Actuator ()

virtual double	getControl (const SimTK::State &s) const
	Convenience method to set controls given scalar (double) valued control. More...

virtual int	numControls () const

virtual void	setForce (const SimTK::State &s, double aForce) const

virtual double	getForce (const SimTK::State &s) const

virtual void	setSpeed (const SimTK::State &s, double aspeed) const

virtual double	getSpeed (const SimTK::State &s) const

void	setMinControl (const double &aMinControl)

double	getMinControl () const

void	setMaxControl (const double &aMaxControl)

double	getMaxControl () const

void	overrideForce (SimTK::State &s, bool flag) const
	Enable/disable an Actuator's override force. More...

bool	isForceOverriden (const SimTK::State &s) const
	return Actuator's override status More...

void	setOverrideForce (SimTK::State &s, double value) const
	set the force value used when the override is true More...

double	getOverrideForce (const SimTK::State &s) const
	return override force More...

	OpenSim_DECLARE_PROPERTY (min_control, double,"Minimum allowed value for control signal. Used primarily when solving ""for control values.")
	Default is -Infinity (no limit). More...

	OpenSim_DECLARE_PROPERTY (max_control, double,"Maximum allowed value for control signal. Used primarily when solving ""for control values.")
	Default is Infinity (no limit). More...

Public Member Functions inherited from OpenSim::Actuator_
	Actuator_ ()

virtual const SimTK::Vector	getDefaultControls ()
	Actuator default controls are zero. More...

virtual const SimTK::VectorView_< double >	getControls (const SimTK::State &s) const

virtual void	getControls (const SimTK::Vector &modelControls, SimTK::Vector &actuatorControls) const
	Convenience methods for getting, setting and adding to actuator controls from/into the model controls. More...

virtual void	setControls (const SimTK::Vector &actuatorControls, SimTK::Vector &modelControls) const
	set actuator controls subvector into the right slot in the system-wide model controls More...

virtual void	addInControls (const SimTK::Vector &actuatorControls, SimTK::Vector &modelControls) const
	add actuator controls to the values already occupying the slot in the system-wide model controls More...

virtual void	computeEquilibrium (SimTK::State &s) const

Public Member Functions inherited from OpenSim::Force
	Force (const Force &aForce)
	Implements a copy constructor just so it can invalidate the SimTK::Force index after copying. More...

Force &	operator= (const Force &aForce)
	Implements a copy assignment operator just so it can invalidate the SimTK::Force index after the assignment. More...

bool	isDisabled (const SimTK::State &s) const
	Return if the Force is disabled or not. More...

void	setDisabled (SimTK::State &s, bool disabled) const
	Set the Force as disabled (true) or not (false). More...

	OpenSim_DECLARE_PROPERTY (isDisabled, bool,"Flag indicating whether the force is disabled or not. Disabled means"" that the force is not active in subsequent dynamics realizations.")
	A Force element is active (enabled) by default. More...

Public Member Functions inherited from OpenSim::ModelComponent
	ModelComponent ()
	Default constructor. More...

	ModelComponent (const std::string &aFileName, bool aUpdateFromXMLNode=true) SWIG_DECLARE_EXCEPTION
	Construct ModelComponent from an XML file. More...

	ModelComponent (SimTK::Xml::Element &aNode)
	Construct ModelComponent from a specific node in an XML document. More...

	ModelComponent (const ModelComponent &source)
	Construct ModelComponent with its contents copied from another ModelComponent; this is a deep copy so nothing is shared with the source after the copy. More...

virtual	~ModelComponent ()
	Destructor is virtual to allow concrete model component cleanup. More...

ModelComponent &	operator= (const ModelComponent &aModelComponent)
	Assignment operator to copy contents of an existing component. More...

const Model &	getModel () const
	Get a const reference to the Model this component is part of. More...

Model &	updModel ()
	Get a modifiable reference to the Model this component is part of. More...

virtual int	getNumStateVariables () const
	Get the number of "Continuous" state variables maintained by the ModelComponent and its specified subcomponents. More...

int	getModelingOption (const SimTK::State &state, const std::string &name) const
	Get a ModelingOption flag for this ModelComponent by name. More...

void	setModelingOption (SimTK::State &state, const std::string &name, int flag) const
	Set the value of a ModelingOption flag for this ModelComponent. More...

double	getStateVariable (const SimTK::State &state, const std::string &name) const
	Get the value of a state variable allocated by this ModelComponent. More...

void	setStateVariable (SimTK::State &state, const std::string &name, double value) const
	Set the value of a state variable allocated by this ModelComponent by name. More...

double	getDiscreteVariable (const SimTK::State &state, const std::string &name) const
	Get the value of a discrete variable allocated by this ModelComponent by name. More...

void	setDiscreteVariable (SimTK::State &state, const std::string &name, double value) const
	Set the value of a discrete variable allocated by this ModelComponent by name. More...

template<typename T >
const T &	getCacheVariable (const SimTK::State &state, const std::string &name) const
	Get the value of a cache variable allocated by this ModelComponent by name. More...

template<typename T >
T &	updCacheVariable (const SimTK::State &state, const std::string &name) const
	Obtain a writable cache variable value allocated by this ModelComponent by name. More...

void	markCacheVariableValid (const SimTK::State &state, const std::string &name) const
	After updating a cache variable value allocated by this ModelComponent, you can mark its value as valid, which will not change until the realization stage falls below the minimum set at the time the cache variable was created. More...

void	markCacheVariableInvalid (const SimTK::State &state, const std::string &name) const
	Mark a cache variable value allocated by this ModelComponent as invalid. More...

bool	isCacheVariableValid (const SimTK::State &state, const std::string &name) const
	Enables the to monitor the validity of the cache variable value using the returned flag. More...

template<typename T >
void	setCacheVariable (const SimTK::State &state, const std::string &name, const T &value) const
	Set cache variable value allocated by this ModelComponent by name. More...

Public Member Functions inherited from OpenSim::Object
virtual	~Object ()
	Virtual destructor for cleanup. More...

virtual Object *	clone () const =0
	Create a new heap-allocated copy of the concrete object to which this Object refers. More...

virtual const std::string &	getConcreteClassName () const =0
	Returns the class name of the concrete Object-derived class of the actual object referenced by this Object, as a string. More...

virtual VisibleObject *	updDisplayer ()
	get Non const pointer to VisibleObject More...

bool	isEqualTo (const Object &aObject) const
	Equality operator wrapper for use from languages not supporting operator overloading. More...

Object &	operator= (const Object &aObject)
	Copy assignment copies he base class fields, including the properties. More...

virtual bool	operator== (const Object &aObject) const
	Determine if two objects are equal. More...

virtual bool	operator< (const Object &aObject) const
	Provide an ordering for objects so they can be put in sorted containers. More...

void	setName (const std::string &name)
	Set the name of the Object. More...

const std::string &	getName () const
	Get the name of this Object. More...

void	setDescription (const std::string &description)
	Set description, a one-liner summary. More...

const std::string &	getDescription () const
	Get description, a one-liner summary. More...

const std::string &	getAuthors () const
	Get Authors of this Object. More...

void	setAuthors (const std::string &authors)
	Set Authors of this object, call this method in your constructor if needed. More...

const std::string &	getReferences () const
	Get references or publications to cite if using this object. More...

void	setReferences (const std::string &references)
	Set references or publications to cite if using this object. More...

int	getNumProperties () const
	Determine how many properties are stored with this Object. More...

const AbstractProperty &	getPropertyByIndex (int propertyIndex) const
	Get a const reference to a property by its index number, returned as an AbstractProperty. More...

AbstractProperty &	updPropertyByIndex (int propertyIndex)
	Get a writable reference to a property by its index number, returned as an AbstractProperty. More...

bool	hasProperty (const std::string &name) const
	Return true if this Object has a property of any type with the given name, which must not be empty. More...

const AbstractProperty &	getPropertyByName (const std::string &name) const
	Get a const reference to a property by its name, returned as an AbstractProperty. More...

AbstractProperty &	updPropertyByName (const std::string &name)
	Get a writable reference to a property by its name, returned as an AbstractProperty. More...

template<class T >
bool	hasProperty () const
	Return true if this Object contains an unnamed, one-object property that contains objects of the given template type T. More...

template<class T >
const Property< T > &	getProperty (const PropertyIndex &index) const
	Get property of known type Property<T> as a const reference; the property must be present and have the right type. More...

template<class T >
Property< T > &	updProperty (const PropertyIndex &index)
	Get property of known type Property<T> as a writable reference; the property must be present and have the right type. More...

void	setObjectIsUpToDateWithProperties ()
	When an object is initialized using the current values of its properties, it can set a flag indicating that it is up to date. More...

bool	isObjectUpToDateWithProperties () const
	Returns `true` if no property's value has changed since the last time setObjectIsUpToDateWithProperties() was called. More...

void	readObjectFromXMLNodeOrFile (SimTK::Xml::Element &objectElement, int versionNumber)
	We're given an XML element from which we are to populate this Object. More...

virtual void	updateXMLNode (SimTK::Xml::Element &parent)
	Serialize this object into the XML node that represents it. More...

bool	getInlined () const
	Inlined means an in-memory Object that is not associated with an XMLDocument. More...

void	setInlined (bool aInlined, const std::string &aFileName="")
	Mark this as inlined or not and optionally provide a file name to associate with the new XMLDocument for the non-inline case. More...

std::string	getDocumentFileName () const
	If there is a document associated with this object then return the file name maintained by the document. More...

void	setAllPropertiesUseDefault (bool aUseDefault)

bool	print (const std::string &fileName)
	Write this Object into an XML file of the given name; conventionally the suffix to use is ".osim". More...

std::string	dump (bool dumpName=false)
	dump the XML representation of this Object into an std::string and return it. More...

void	clearObjectIsUpToDateWithProperties ()
	For testing or debugging purposes, manually clear the "object is up to date with respect to properties" flag. More...

virtual bool	isA (const char *type) const
	The default implementation returns true only if the supplied string is "Object"; each Object-derived class overrides this to match its own class name. More...

const std::string &	toString () const
	Wrapper to be used on Java side to display objects in tree; this returns just the object's name. More...

PropertySet &	getPropertySet ()
	OBSOLETE: Get a reference to the PropertySet maintained by the Object. More...

const PropertySet &	getPropertySet () const

Protected Member Functions
double	computeActuation (const SimTK::State &s) const override

SimTK::Vec3	computePathColor (const SimTK::State &state) const override
	Override PathActuator method to calculate a color for use when the ClutchedPathSpring's path is displayed in the visualizer. More...

void	addToSystem (SimTK::MultibodySystem &system) const override
	Implement ModelComponent interface. More...

void	initStateFromProperties (SimTK::State &state) const override
	Subclass should override; be sure to invoke Force::initStateFromProperties() at the beginning of the overriding method. More...

void	setPropertiesFromState (const SimTK::State &state) override
	Subclass should override; be sure to invoke Force::setPropertiesFromState() at the beginning of the overriding method. More...

Array< std::string >	getStateVariableNames () const override
	Get the names of "continuous" state variables maintained by the ModelComponent and its subcomponents. More...

SimTK::SystemYIndex	getStateVariableSystemIndex (const std::string &stateVariableName) const override
	Get the System Index of a state variable allocated by this ModelComponent. More...

SimTK::Vector	computeStateVariableDerivatives (const SimTK::State &s) const override
	If a model component has allocated any continuous state variables using the addStateVariable() method, then computeStateVariableDerivatives() must be implemented to provide time derivatives for those states. More...

Protected Member Functions inherited from OpenSim::PathActuator
void	connectToModel (Model &aModel) override
	Extension of parent class method; derived classes may extend further. More...

void	realizeDynamics (const SimTK::State &state) const override
	Extension of parent class method; derived classes may extend further. More...

Protected Member Functions inherited from OpenSim::Actuator
double	computeOverrideForce (const SimTK::State &s) const

OpenSim::Array< std::string >	getRecordLabels () const
	Methods to query a Force for the value actually applied during simulation The names of the quantities (column labels) is returned by this first function getRecordLabels() More...

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. More...

Protected Member Functions inherited from OpenSim::Actuator_
virtual void	updateGeometry ()

Protected Member Functions inherited from OpenSim::Force
	Force ()
	Default constructor sets up Force-level properties; can only be called from a derived class constructor. More...

	Force (SimTK::Xml::Element &node)
	Deserialization from XML, necessary so that derived classes can (de)serialize. More...

virtual double	computePotentialEnergy (const SimTK::State &state) const
	Subclasses may optionally override this method to compute a contribution to the potential energy of the system. More...

void	applyForceToPoint (const SimTK::State &state, const OpenSim::Body &body, const SimTK::Vec3 &point, const SimTK::Vec3 &force, SimTK::Vector_< SimTK::SpatialVec > &bodyForces) const
	Apply a force at a particular point (a "station") on a given body. More...

void	applyTorque (const SimTK::State &state, const OpenSim::Body &body, const SimTK::Vec3 &torque, SimTK::Vector_< SimTK::SpatialVec > &bodyForces) const
	Apply a torque to a particular body. More...

void	applyGeneralizedForce (const SimTK::State &state, const Coordinate &coord, double force, SimTK::Vector &generalizedForces) const
	Apply a generalized force. More...

Protected Member Functions inherited from OpenSim::ModelComponent
virtual void	generateDecorations (bool fixed, const ModelDisplayHints &hints, const SimTK::State &state, SimTK::Array_< SimTK::DecorativeGeometry > &appendToThis) const
	Optional method for generating arbitrary display geometry that reflects this ModelComponent at the specified state. More...

virtual void	realizeTopology (SimTK::State &state) const
	Obtain state resources that are needed unconditionally, and perform computations that depend only on the system topology. More...

virtual void	realizeModel (SimTK::State &state) const
	Obtain state resources that may be needed, depending on modeling options, and perform computations that depend only on topology and selected modeling options. More...

virtual void	realizeInstance (const SimTK::State &state) const
	Perform computations that depend only on instance variables, like lengths and masses. More...

virtual void	realizeTime (const SimTK::State &state) const
	Perform computations that depend only on time and earlier stages. More...

virtual void	realizePosition (const SimTK::State &state) const
	Perform computations that depend only on position-level state variables and computations performed in earlier stages (including time). More...

virtual void	realizeVelocity (const SimTK::State &state) const
	Perform computations that depend only on velocity-level state variables and computations performed in earlier stages (including position, and time). More...

virtual void	realizeAcceleration (const SimTK::State &state) const
	Perform computations that may depend on applied forces. More...

virtual void	realizeReport (const SimTK::State &state) const
	Perform computations that may depend on anything but are only used for reporting and cannot affect subsequent simulation behavior. More...

void	includeAsSubComponent (ModelComponent *aComponent)
	Include another ModelComponent as a Subcomponent of this ModelComponent. More...

void	addModelingOption (const std::string &optionName, int maxFlagValue) const
	Add a modeling option (integer flag stored in the State) for use by this ModelComponent. More...

void	addStateVariable (const std::string &stateVariableName, SimTK::Stage invalidatesStage=SimTK::Stage::Dynamics) const
	Add a continuous system state variable belonging to this ModelComponent, and assign a name by which to refer to it. More...

void	addDiscreteVariable (const std::string &discreteVariableName, SimTK::Stage invalidatesStage) const
	Add a system discrete variable belonging to this ModelComponent, give it a name by which it can be referenced, and declare the lowest Stage that should be invalidated if this variable's value is changed. More...

template<class T >
void	addCacheVariable (const std::string &cacheVariableName, const T &variablePrototype, SimTK::Stage dependsOnStage) const
	Add a state cache entry belonging to this ModelComponent to hold calculated values that must be automatically invalidated when certain state values change. More...

const int	getStateIndex (const std::string &name) const
	Get the index of a ModelComponent's continuous state variable in the Subsystem for allocations. More...

const SimTK::DiscreteVariableIndex	getDiscreteVariableIndex (const std::string &name) const
	Get the index of a ModelComponent's discrete variable in the Subsystem for allocations. More...

const SimTK::CacheEntryIndex	getCacheVariableIndex (const std::string &name) const
	Get the index of a ModelComponent's cache variable in the Subsystem for allocations. More...

Protected Member Functions inherited from OpenSim::Object
	Object ()
	The default constructor is only for use by constructors of derived types. More...

	Object (const std::string &fileName, bool aUpdateFromXMLNode=true) SWIG_DECLARE_EXCEPTION
	Constructor from a file, to be called from other constructors that take a file as input. More...

	Object (const Object &source)
	Copy constructor is invoked automatically by derived classes with default copy constructors; otherwise it must be invoked explicitly. More...

	Object (SimTK::Xml::Element &aElement)
	Construct the base class portion of an Object from a given Xml element that describes this Object. More...

template<class T >
PropertyIndex	addProperty (const std::string &name, const std::string &comment, const T &value)
	Define a new single-value property of known type T, with the given name, associated comment, and initial value. More...

template<class T >
PropertyIndex	addOptionalProperty (const std::string &name, const std::string &comment)
	Add an optional property, meaning it can contain either no value or a single value. More...

template<class T >
PropertyIndex	addOptionalProperty (const std::string &name, const std::string &comment, const T &value)
	Add an optional property, meaning it can contain either no value or a single value. More...

template<class T >
PropertyIndex	addListProperty (const std::string &name, const std::string &comment, int minSize, int maxSize)
	Define a new list-valued property of known type T, with the given name, associated comment, minimum (==0) and maximum (>0) allowable list lengths, and a zero-length initial value. More...

template<class T , template< class > class Container>
PropertyIndex	addListProperty (const std::string &name, const std::string &comment, int minSize, int maxSize, const Container< T > &valueList)
	Define a new list-valued property as above, but assigning an initial value via some templatized container class that supports size() and indexing. More...

PropertyIndex	getPropertyIndex (const std::string &name) const
	Look up a property by name and return its PropertyIndex if it is found. More...

template<class T >
PropertyIndex	getPropertyIndex () const
	Look up an unnamed property by the type of object it contains, and return its PropertyIndex if it is found. More...

void	updateFromXMLDocument ()
	Use this method only if you're deserializing from a file and the object is at the top level; that is, primarily in constructors that take a file name as input. More...

void	setDocument (XMLDocument *doc)
	Unconditionally set the XMLDocument associated with this object. More...

const XMLDocument *	getDocument () const
	Get a const pointer to the document (if any) associated with this object. More...

XMLDocument *	updDocument ()
	Get a writable pointer to the document (if any) associated with this object. More...

Additional Inherited Members
Static Public Member Functions inherited from OpenSim::Object
static void	registerType (const Object &defaultObject)
	Register an instance of a class; if the class is already registered it will be replaced. More...

static void	renameType (const std::string &oldTypeName, const std::string &newTypeName)
	Support versioning by associating the current Object type with an old name. More...

static const Object *	getDefaultInstanceOfType (const std::string &concreteClassName)
	Return a pointer to the default instance of the registered (concrete) Object whose class name is given, or NULL if the type is not registered. More...

template<class T >
static bool	isObjectTypeDerivedFrom (const std::string &concreteClassName)
	Return true if the given concrete object type represents a subclass of the template object type T, and thus could be referenced with a T*. More...

static Object *	newInstanceOfType (const std::string &concreteClassName)
	Create a new instance of the concrete Object type whose class name is given as concreteClassName. More...

static void	getRegisteredTypenames (Array< std::string > &typeNames)
	Retrieve all the typenames registered so far. More...

template<class T >
static void	getRegisteredObjectsOfGivenType (ArrayPtrs< T > &rArray)
	Return an array of pointers to the default instances of all registered (concrete) Object types that derive from a given Object-derived type that does not have to be concrete. More...

static void	PrintPropertyInfo (std::ostream &os, const std::string &classNameDotPropertyName)
	Dump formatted property information to a given output stream, useful for creating a "help" facility for registered objects. More...

static void	PrintPropertyInfo (std::ostream &os, const std::string &className, const std::string &propertyName)
	Same as the other signature but the class name and property name are provided as two separate strings. More...

static Object *	makeObjectFromFile (const std::string &fileName)
	Create an OpenSim object whose type is based on the tag at the root node of the XML file passed in. More...

static const std::string &	getClassName ()
	Return the name of this class as a string; i.e., "Object". More...

static void	setSerializeAllDefaults (bool shouldSerializeDefaults)
	Static function to control whether all registered objects and their properties are written to the defaults section of output files rather than only those values for which the default was explicitly overwritten when read in from an input file or set programmatically. More...

static bool	getSerializeAllDefaults ()
	Report the value of the "serialize all defaults" flag. More...

static bool	isKindOf (const char *type)
	Returns true if the passed-in string is "Object"; each Object-derived class defines a method of this name for its own class name. More...

static void	setDebugLevel (int newLevel)
	Set the debug level to get verbose output. More...

static int	getDebugLevel ()
	Get current setting of debug level. More...

static Object *	SafeCopy (const Object *aObject)
	Use the clone() method to duplicate the given object unless the pointer is null in which case null is returned. More...

static void	RegisterType (const Object &defaultObject)
	OBSOLETE alternate name for registerType(). More...

static void	RenameType (const std::string &oldName, const std::string &newName)
	OBSOLETE alternate name for renameType(). More...

Static Public Attributes inherited from OpenSim::Object
static const std::string	DEFAULT_NAME
	Name used for default objects when they are serialized. More...

Protected Attributes inherited from OpenSim::Actuator_
int	_controlIndex

Related Functions inherited from OpenSim::Object
#define	OpenSim_DECLARE_CONCRETE_OBJECT(ConcreteClass, SuperClass)
	Macro to be included as the first line of the class declaration for any non-templatized, concrete class that derives from OpenSim::Object. More...

#define	OpenSim_DECLARE_ABSTRACT_OBJECT(ConcreteClass, SuperClass)
	Macro to be included as the first line of the class declaration for any still-abstract class that derives from OpenSim::Object. More...

#define	OpenSim_DECLARE_CONCRETE_OBJECT_T(ConcreteClass, TArg, SuperClass)
	Macro to be included as the first line of the class declaration for any templatized, concrete class that derives from OpenSim::Object, like Set<T>. More...

#define	OpenSim_DECLARE_ABSTRACT_OBJECT_T(ConcreteClass, TArg, SuperClass)
	Macro to be included as the first line of the class declaration for any templatized, still-abstract class that derives from OpenSim::Object. More...

Detailed Description

The ClutchedPathSpring is an actuator that has passive path spring behavior only when the clutch is engaged.

The clutch is engaged by a control signal of 1 and is off for a control signal of 0. Off means the spring is not engaged and the path is free to change length with the motion of the bodies it is connected to. The tension produced by the spring is proportional to the stretch (z) from the instant that the clutch is engaged.

The spring tension = x*(K*z)*(1+D*Ldot), where

x is the control signal to the actuator
z is the stretch in the spring
Ldot is the lengthening speed of the actuator
K is the spring's linear stiffness (N/m)
D is the spring's dissipation factor

The ClutchedPathSpring maintains the "stretch", z, as an internal state with the following dynamics:

dz/dt =	Ldot, when x>0 (clutch is engaged)
	-(1/Tau)*z, (decay to zero), otherwise

Note that the control signal, x, is clamped to (0,1).

Author: Ajay Seth

Constructor & Destructor Documentation

OpenSim::ClutchedPathSpring::ClutchedPathSpring ( )

OpenSim::ClutchedPathSpring::ClutchedPathSpring	(	const std::string &	name,
		double	stiffness,
		double	dissipation,
		double	relaxationTau,
		double	stretch0 = `0.0`
	)

Convenience constructor with ClutchedPathSpring parameters.

Parameters

name	the name of a ClutchedPathSpring instance
stiffness	the spring stiffness (K) in N/m
dissipation	the dissipation factor (D) in s/m
relaxationTau	the spring relaxation time constant (Tau) in s
stretch0	the initial stretch of the spring in m

Member Function Documentation

void OpenSim::ClutchedPathSpring::addToSystem ( SimTK::MultibodySystem & system) const

overrideprotectedvirtual

Implement ModelComponent interface.

Reimplemented from OpenSim::Actuator.

double OpenSim::ClutchedPathSpring::computeActuation ( const SimTK::State & s) const

overrideprotectedvirtual

Reimplemented from OpenSim::PathActuator.

SimTK::Vec3 OpenSim::ClutchedPathSpring::computePathColor ( const SimTK::State & state) const

overrideprotectedvirtual

Override PathActuator method to calculate a color for use when the ClutchedPathSpring's path is displayed in the visualizer.

Parameters

[in] state A SimTK::State already realized through Stage::Velocity. Do not attempt to realize it any further.

Returns: The desired color for the path as an RGB vector with each component ranging from 0 to 1, or NaN to indicate that the color should not be changed.

Reimplemented from OpenSim::PathActuator.

SimTK::Vector OpenSim::ClutchedPathSpring::computeStateVariableDerivatives ( const SimTK::State & s) const

overrideprotectedvirtual

If a model component has allocated any continuous state variables using the addStateVariable() method, then computeStateVariableDerivatives() must be implemented to provide time derivatives for those states.

Override to return a Vector of the same size as the number of state variables defined and in order added to the system (also

See Also: addToSystem()). Default returns empty (no derivatives are defined). Implement like this:
SimTK::Vector computeStateVariableDerivatives(const SimTK::State& s) const {

// Collect derivatives from parent class and above first.

SimTK::Vector derivs = Super::computeStateVariableDerivatives(s);

const int n = derivs.size();

derivs.resizeKeep(n + myNumStateVariables); // grow

for (int i=0; i < myNumStateVariables; ++i)

derivs[n+i] = ...; // i'th state variable derivative

return derivs;

}

This method is invoked from the base class realizeAcceleration() method.

Reimplemented from OpenSim::ModelComponent.

double OpenSim::ClutchedPathSpring::getDissipation ( ) const

inline

Spring dissipation factor in s/m when clutch is engaged.

double OpenSim::ClutchedPathSpring::getInitialStretch ( )

inline

Initial spring stretch in m.

Array<std::string> OpenSim::ClutchedPathSpring::getStateVariableNames ( ) const

overrideprotectedvirtual

Get the names of "continuous" state variables maintained by the ModelComponent and its subcomponents.

Reimplemented from OpenSim::ModelComponent.

SimTK::SystemYIndex OpenSim::ClutchedPathSpring::getStateVariableSystemIndex ( const std::string & stateVariableName) const

overrideprotectedvirtual

Get the System Index of a state variable allocated by this ModelComponent.

Returns an InvalidIndex if no state variable with the name provided is found.

Parameters

stateVariableName the name of the state variable

Reimplemented from OpenSim::ModelComponent.

double OpenSim::ClutchedPathSpring::getStiffness ( ) const

inline

Spring stiffness in N/m when clutch is engaged.

double OpenSim::ClutchedPathSpring::getStretch ( const SimTK::State & s) const

The stretch in the PathSpring.

The value of the stretch can only be obtained after the system has been realized to Stage::Position

double OpenSim::ClutchedPathSpring::getTension ( const SimTK::State & s) const

The tension generated by the PathSpring.

The value of the tension can only be obtained after the system has been realized to Stage::Dynamics

void OpenSim::ClutchedPathSpring::initStateFromProperties ( SimTK::State & state) const

overrideprotectedvirtual

Subclass should override; be sure to invoke Force::initStateFromProperties() at the beginning of the overriding method.

Reimplemented from OpenSim::Force.

OpenSim::ClutchedPathSpring::OpenSim_DECLARE_PROPERTY	(	stiffness	,
		double	,
		"The linear stiffness (N/m) of the ClutchedPathSpring"
	)

OpenSim::ClutchedPathSpring::OpenSim_DECLARE_PROPERTY	(	dissipation	,
		double	,
		"The dissipation factor (s/m) of the ClutchedPathSpring"
	)

OpenSim::ClutchedPathSpring::OpenSim_DECLARE_PROPERTY	(	relaxation_time_constant	,
		double	,
		"The time constant (s) for the spring to relax (go slack) after the clutch ""is disengaged (i.e. control == 0). If the clutch is re-engaged within the ""relaxation period there will be residual tension in the spring."
	)

OpenSim::ClutchedPathSpring::OpenSim_DECLARE_PROPERTY	(	initial_stretch	,
		double	,
		"The initial stretch (m) of the spring element. Note if the clucth is ""not	engaged,
		the actuator will 'slip'until there is no stretch according""to the relaxation_time_constant."
	)

void OpenSim::ClutchedPathSpring::setDissipation ( double dissipation)

void OpenSim::ClutchedPathSpring::setInitialStretch ( double stretch0)

void OpenSim::ClutchedPathSpring::setPropertiesFromState ( const SimTK::State & state)

overrideprotectedvirtual

Subclass should override; be sure to invoke Force::setPropertiesFromState() at the beginning of the overriding method.

Reimplemented from OpenSim::Force.

void OpenSim::ClutchedPathSpring::setStiffness ( double stiffness)

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

/home/fitze/repos/opensim/Branches/OpenSim32ForDoxygen/OpenSim/Actuators/ClutchedPathSpring.h

Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation