Computes muscle activation using a modified version of the first-order dynamic models used by Thelen (2003) and Winters (1995). More...

Inheritance diagram for OpenSim::FirstOrderMuscleActivationDynamics:

OpenSim Properties, Sockets, Outputs, Inputs
Properties (single-value)
double	activation_time_constant
	"Activation time constant (in seconds)" More...

double	deactivation_time_constant
	"Deactivation time constant (in seconds)" More...

OpenSim Properties, Sockets, Outputs, Inputs inherited from OpenSim::MuscleActivationDynamics
double	minimum_activation
	"Smallest permitted activation value" More...

double	maximum_activation
	"Largest permitted activation value" More...

double	default_activation
	"Default activation value" More...

OpenSim Properties, Sockets, Outputs, Inputs inherited from OpenSim::Component
Component	components
	"List of components that this component owns and serializes." More...

Public Member Functions
double	getActivation (const SimTK::State &s) const override
	Get the current activation from the state. More...

void	setActivation (SimTK::State &s, double activation) const override
	Set activation state variable to the value provided. More...

Property-related functions
const double &	get_activation_time_constant () const
	Get the value of the activation_time_constant property. More...

double &	upd_activation_time_constant ()
	Get a writable reference to the activation_time_constant property. More...

void	set_activation_time_constant (const double &value)
	Set the value of the activation_time_constant property. More...

const double &	get_deactivation_time_constant () const
	Get the value of the deactivation_time_constant property. More...

double &	upd_deactivation_time_constant ()
	Get a writable reference to the deactivation_time_constant property. More...

void	set_deactivation_time_constant (const double &value)
	Set the value of the deactivation_time_constant property. More...

Constructors
	FirstOrderMuscleActivationDynamics ()
	Creates a first-order activation dynamic model with the default property values and assigns it a default name. More...

	FirstOrderMuscleActivationDynamics (const std::string &name, ExcitationGetter *getter)
	Creates a first-order activation dynamic model with the default property values, the specified name, and the specified ExcitationGetter. More...

Accessors and Mutators
double	getActivationTimeConstant () const
	Get the activation time constant. More...

void	setActivationTimeConstant (double activationTimeConstant)
	Set the activation time constant to a value greater than zero. More...

double	getDeactivationTimeConstant () const
	Get the deactivation time constant. More...

void	setDeactivationTimeConstant (double deactivationTimeConstant)
	Set the deactivation time constant to a value greater than zero. More...

ModelComponent Interface Requirements
void	extendAddToSystem (SimTK::MultibodySystem &system) const override
	Adds activation to the state. More...

void	extendInitStateFromProperties (SimTK::State &s) const override
	Initializes the activation state variable to `default_activation`. More...

void	extendSetPropertiesFromState (const SimTK::State &s) override
	Sets `default_activation` to the current value of the activation state variable. More...

void	computeStateVariableDerivatives (const SimTK::State &s) const override
	Calculates the time derivative of activation using a first-order dynamic model. More...

Public Member Functions inherited from OpenSim::MuscleActivationDynamics
double	getExcitation (const SimTK::State &s) const
	Get the muscle excitation using the ExcitationGetter object. More...

const double &	get_minimum_activation () const
	Get the value of the minimum_activation property. More...

double &	upd_minimum_activation ()
	Get a writable reference to the minimum_activation property. More...

void	set_minimum_activation (const double &value)
	Set the value of the minimum_activation property. More...

const double &	get_maximum_activation () const
	Get the value of the maximum_activation property. More...

double &	upd_maximum_activation ()
	Get a writable reference to the maximum_activation property. More...

void	set_maximum_activation (const double &value)
	Set the value of the maximum_activation property. More...

const double &	get_default_activation () const
	Get the value of the default_activation property. More...

double &	upd_default_activation ()
	Get a writable reference to the default_activation property. More...

void	set_default_activation (const double &value)
	Set the value of the default_activation property. More...

	MuscleActivationDynamics ()
	Creates an activation dynamic model with the default property values and assigns it a default name. More...

	MuscleActivationDynamics (const std::string &name, ExcitationGetter *getter)
	Creates an activation dynamic model with the default property values, the specified name, and the specified ExcitationGetter. More...

	~MuscleActivationDynamics ()
	Deletes the ExcitationGetter object. More...

double	getMinimumActivation () const
	Get the smallest permitted activation value. More...

void	setMinimumActivation (double minimumActivation)
	Set the smallest permitted activation value. More...

double	getMaximumActivation () const
	Get the largest permitted activation value. More...

void	setMaximumActivation (double maximumActivation)
	Set the largest permitted activation value. More...

double	getDefaultActivation () const
	Get the default activation value. More...

void	setDefaultActivation (double defaultActivation)
	Set the default activation value. More...

void	setExcitationGetter (ExcitationGetter *getter)
	Define an ExcitationGetter for obtaining muscle excitation. More...

void	assign (Object &aObject) override
	This allows copy assignment in the Java GUI. More...

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

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

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

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

void	connectToModel (Model &model)
	Connect this ModelComponent to its aggregate- a Model. 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...

bool	hasModel () const
	Does this ModelComponent have a Model associated with it? More...

void	preScale (const SimTK::State &s, const ScaleSet &scaleSet)
	Perform any computations that must occur before ModelComponent::scale() is invoked on all ModelComponents in the Model. More...

void	scale (const SimTK::State &s, const ScaleSet &scaleSet)
	Scale the ModelComponent. More...

void	postScale (const SimTK::State &s, const ScaleSet &scaleSet)
	Perform any computations that must occur after ModelComponent::scale() has been invoked on all ModelComponents in the Model. More...

void	assign (Object &aObject) override
	This allows copy assignment in the Java GUI. More...

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

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

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

	Component (const Component &)=default
	Use default copy constructor and assignment operator. More...

Component &	operator= (const Component &)=default

virtual	~Component ()=default
	Destructor is virtual to allow concrete Component to cleanup. More...

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 Component at the specified state. More...

const SimTK::MultibodySystem &	getSystem () const
	Get the underlying MultibodySystem that this component is connected to. More...

bool	hasSystem () const
	Check if this component has an underlying MultibodySystem. More...

bool	isComponentInOwnershipTree (const Component *component) const
	Does the provided component already exist anywhere in the ownership tree (not just subcomponents of this component)? More...

void	addComponent (Component *subcomponent)
	Add a Component (as a subcomponent) of this component. More...

template<typename T = Component>
ComponentList< const T >	getComponentList () const
	Get an iterator through the underlying subcomponents that this component is composed of. More...

template<typename T = Component>
ComponentList< T >	updComponentList ()
	Similar to getComponentList(), except the resulting list allows one to modify the components. More...

template<typename T = Component>
unsigned	countNumComponents () const
	Uses getComponentList<T>() to count the number of underlying subcomponents of the specified type. More...

std::string	getAbsolutePathString () const
	Get the complete (absolute) pathname for this Component to its ancestral Component, which is the root of the tree to which this Component belongs. More...

ComponentPath	getAbsolutePath () const
	Return a ComponentPath of the absolute path of this Component. More...

std::string	getRelativePathString (const Component &wrt) const
	Get the relative path of this Component with respect to another Component, as a string. More...

ComponentPath	getRelativePath (const Component &wrt) const
	Get the relative path of this Component with respect to another Component. More...

bool	hasComponent (const std::string &pathname) const
	Query if there is a component (of any type) at the specified path name. More...

template<class C = Component>
bool	hasComponent (const std::string &pathname) const
	Query if there is a component of a given type at the specified path name. More...

template<class C = Component>
const C &	getComponent (const std::string &pathname) const
	Get a unique subcomponent of this Component by its path name and type 'C'. More...

template<class C = Component>
const C &	getComponent (const ComponentPath &pathname) const

const Component &	getComponent (const std::string &pathname) const
	Similar to the templatized getComponent(), except this returns the component as the generic Component type. More...

template<class C = Component>
C &	updComponent (const std::string &name)
	Get a writable reference to a subcomponent. More...

template<class C = Component>
C &	updComponent (const ComponentPath &name)

Component &	updComponent (const std::string &pathname)
	Similar to the templatized updComponent(), except this returns the component as the generic Component type. More...

unsigned	printComponentsMatching (const std::string &substring) const
	Print a list to the console of all components whose absolute path name contains the given string. More...

int	getNumStateVariables () const
	Get the number of "continuous" state variables maintained by the Component and its subcomponents. More...

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

template<class C = Component>
const C *	findComponent (const ComponentPath &pathToFind) const
	Find a Component to which this Component is an ancestor—in other words, a Component that is directly owned by this Component or is owned by one of its sub-components, sub-sub-components, etc. More...

template<class C = Component>
const C *	findComponent (const std::string &pathToFind) const
	Same as findComponent(const ComponentPath&), but accepting a string (a path or just a name) as input. More...

const StateVariable *	traverseToStateVariable (const std::string &pathName) const
	Get a StateVariable anywhere in the Component tree, given a StateVariable path. More...

void	finalizeFromProperties ()
	Define a Component's internal data members and structure according to its properties. More...

void	finalizeConnections (Component &root)
	Satisfy the Component's connections specified by its Sockets and Inputs. More...

void	clearConnections ()
	Disconnect/clear this Component from its aggregate component. More...

void	addToSystem (SimTK::MultibodySystem &system) const
	Have the Component add itself to the underlying computational System. More...

void	initStateFromProperties (SimTK::State &state) const
	Initialize Component's state variable values from its properties. More...

void	setPropertiesFromState (const SimTK::State &state)
	Set Component's properties given a state. More...

int	getNumSockets () const
	Get the number of Sockets in this Component. More...

std::vector< std::string >	getSocketNames ()
	Collect and return the names of the sockets in this component. More...

template<typename T >
const T &	getConnectee (const std::string &name) const
	Get the "connectee" object that the Component's Socket is bound to. More...

const Object &	getConnectee (const std::string &name) const
	Get the connectee as an Object. More...

const AbstractSocket &	getSocket (const std::string &name) const
	Get an AbstractSocket for the given socket name. More...

AbstractSocket &	updSocket (const std::string &name)
	Get a writable reference to the AbstractSocket for the given socket name. More...

template<typename T >
const Socket< T > &	getSocket (const std::string &name) const
	Get a const reference to the concrete Socket provided by this Component by name. More...

template<typename T >
Socket< T > &	updSocket (const std::string &name)
	Get a writable reference to the concrete Socket provided by this Component by name. More...

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

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

template<typename T >
const T &	getInputValue (const SimTK::State &state, const std::string &name) const
	Get the Input value that this component is dependent on. More...

template<typename T >
const T &	getOutputValue (const SimTK::State &state, const std::string &name) const
	Get the Output value provided by this Component by name. More...

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

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

SimTK::Vector	getStateVariableValues (const SimTK::State &state) const
	Get all values of the state variables allocated by this Component. More...

void	setStateVariableValues (SimTK::State &state, const SimTK::Vector &values) const
	Set all values of the state variables allocated by this Component. More...

double	getStateVariableDerivativeValue (const SimTK::State &state, const std::string &name) const
	Get the value of a state variable derivative computed by this Component. More...

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

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

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

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

void	markCacheVariableValid (const SimTK::State &state, const std::string &name) const
	After updating a cache variable value allocated by this Component, 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 Component as invalid. More...

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

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

void	printSubcomponentInfo () const
	List all subcomponents by name and recurse into these components to list their subcomponents, and so on. More...

void	printSocketInfo () const
	List all the Sockets of this component and whether or not they are connected. More...

void	printInputInfo () const
	List all the inputs of this component and whether or not they are connected. More...

template<typename C >
void	printSubcomponentInfo () const

void	printOutputInfo (const bool includeDescendants=true) const
	Print outputs of this component and optionally, those of all subcomponents. More...

void	assign (Object &aObject) override
	This allows copy assignment in the Java GUI. More...

int	getNumInputs () const
	Access the number of Inputs that this component has. More...

int	getNumOutputs () const
	Access the number of Outputs that this component has. More...

std::vector< std::string >	getInputNames () const
	Collect and return the names of Inputs in this component as an std::vector. More...

std::vector< std::string >	getOutputNames () const
	Collect and return the names of Outputs in this component as an std::vector. More...

const AbstractInput &	getInput (const std::string &name) const
	Get an Input provided by this Component by name. More...

AbstractInput &	updInput (const std::string &name)
	Get a writable reference to an Input provided by this Component by name. More...

template<typename T >
const Input< T > &	getInput (const std::string &name) const
	Get a concrete Input that you can directly ask for its values. More...

const AbstractOutput &	getOutput (const std::string &name) const
	Get the Output provided by this Component by name. More...

AbstractOutput &	updOutput (const std::string &name)
	Get a writable reference to an Output provided by this Component by name. More...

SimTK::IteratorRange< OutputConstIterator >	getOutputs () const
	Iterate through all Outputs of this component. More...

const Component &	getOwner () const
	Access the owner of this Component. More...

bool	hasOwner () const
	(For advanced users) Check if this Component has an owner. More...

const Component &	getRoot () const
	Obtain the root Component, which is this component if it is orphaned. More...

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

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...

void	updateXMLNode (SimTK::Xml::Element &parent, const AbstractProperty *prop=nullptr) const
	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...

int	getDocumentFileVersion () const
	If there is a document associated with this object then return its version number. More...

void	setAllPropertiesUseDefault (bool aUseDefault)

bool	print (const std::string &fileName) const
	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...

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

Public Types
typedef FirstOrderMuscleActivationDynamics	Self
	This typedef might be useful within the member functions of this class. More...

typedef MuscleActivationDynamics	Super
	Use this typedef to refer to the superclass of this class. More...

Public Types inherited from OpenSim::MuscleActivationDynamics
typedef MuscleActivationDynamics	Self
	This typedef might be useful within the member functions of this class. More...

typedef ModelComponent	Super
	Use this typedef to refer to the superclass of this class. More...

Public Types inherited from OpenSim::ModelComponent
typedef ModelComponent	Self
	This typedef might be useful within the member functions of this class. More...

typedef Component	Super
	Use this typedef to refer to the superclass of this class. More...

Public Types inherited from OpenSim::Component
typedef Component	Self
	This typedef might be useful within the member functions of this class. More...

typedef Object	Super
	Use this typedef to refer to the superclass of this class. More...

typedef std::map< std::string, SimTK::ClonePtr< AbstractOutput > >::const_iterator	OutputConstIterator
	Define OutputConstIterator for convenience. More...

Auto-generated functions
static FirstOrderMuscleActivationDynamics *	safeDownCast (OpenSim::Object *obj)
	For use in MATLAB and Python to access the concrete class. More...

static const std::string &	getClassName ()
	This returns "FirstOrderMuscleActivationDynamics". More...

void	assign (Object &aObject) override
	This allows copy assignment in the Java GUI. More...

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

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

Additional Inherited Members
Static Public Member Functions inherited from OpenSim::MuscleActivationDynamics
static MuscleActivationDynamics *	safeDownCast (OpenSim::Object *obj)
	For use in MATLAB and Python to access the concrete class. More...

static const std::string &	getClassName ()
	This returns "MuscleActivationDynamics". More...

Static Public Member Functions inherited from OpenSim::ModelComponent
static ModelComponent *	safeDownCast (OpenSim::Object *obj)
	For use in MATLAB and Python to access the concrete class. More...

static const std::string &	getClassName ()
	This returns "ModelComponent". More...

Static Public Member Functions inherited from OpenSim::Component
static Component *	safeDownCast (OpenSim::Object *obj)
	For use in MATLAB and Python to access the concrete class. More...

static const std::string &	getClassName ()
	This returns "Component". More...

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

static bool	PrintPropertyInfo (std::ostream &os, const std::string &className, const std::string &propertyName, bool printFlagInfo=true)
	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 Member Functions inherited from OpenSim::MuscleActivationDynamics
double	clampToValidInterval (double val) const
	Clamp to the interval [minimum_activation, maximum_activation]. More...

Protected Member Functions inherited from OpenSim::ModelComponent
const SimTK::Vec3 &	getScaleFactors (const ScaleSet &scaleSet, const Frame &frame) const
	Get the scale factors corresponding to the base OpenSim::Body of the specified Frame. More...

virtual void	extendPreScale (const SimTK::State &s, const ScaleSet &scaleSet)
	Perform any computations that must occur before ModelComponent::scale() is invoked on all ModelComponents in the Model. More...

virtual void	extendScale (const SimTK::State &s, const ScaleSet &scaleSet)
	Scale the ModelComponent. More...

virtual void	extendPostScale (const SimTK::State &s, const ScaleSet &scaleSet)
	Perform any computations that must occur after ModelComponent::scale() has been invoked on all ModelComponents in the Model. More...

void	updateFromXMLNode (SimTK::Xml::Element &aNode, int versionNumber) override
	Handle a change in XML syntax for Sockets. More...

void	extendFinalizeFromProperties () override
	Perform any time-invariant calculations, data structure initializations, or other configuration based on the component's properties to form a functioning (but not yet connected) component. More...

virtual void	extendConnectToModel (Model &model)
	Perform any necessary initializations required to connect the component into the Model, and check for error conditions. More...

Protected Member Functions inherited from OpenSim::Component
	SimTK_DEFINE_UNIQUE_INDEX_TYPE (MemberSubcomponentIndex)

template<class C = Component>
MemberSubcomponentIndex	constructSubcomponent (const std::string &name)
	Construct a subcomponent as a data member of this Component. More...

template<class C = Component>
const C &	getMemberSubcomponent (MemberSubcomponentIndex ix) const

template<class C = Component>
C &	updMemberSubcomponent (MemberSubcomponentIndex ix)

void	adoptSubcomponent (Component *subcomponent)
	Adopt a component as a subcomponent of this Component. More...

size_t	getNumImmediateSubcomponents () const
	Get the number of Subcomponents immediately owned by this Component. More...

size_t	getNumMemberSubcomponents () const
	Get the number of Subcomponents that are data members of this Component. More...

size_t	getNumPropertySubcomponents () const
	Get the number of Subcomponents that are properties of this Component. More...

size_t	getNumAdoptedSubcomponents () const
	Get the number of Subcomponents adopted by this Component. More...

std::vector< SimTK::ReferencePtr< const Component > >	getImmediateSubcomponents () const
	Access this Component's immediate subcomponents (not those owned by subcomponents) More...

template<class C >
const C *	traversePathToComponent (ComponentPath path) const

void	setNextSubcomponentInSystem (const Component &sub) const
	Helper method to enable Component makers to specify the order of their subcomponents to be added to the System during addToSystem(). More...

void	resetSubcomponentOrder ()
	resetSubcomponentOrder clears this Component's list of ordered subcomponents (but otherwise leaves subcomponents untouched). More...

const Component &	get_components (int i) const
	Get the value of the i-th element of the components property. More...

Component &	upd_components (int i)
	Get a writable reference to the i-th element of the components property. More...

void	set_components (int i, const Component &value)
	Set the value of the i-th element of components property. More...

int	append_components (const Component &value)
	Append an element to the components property. More...

virtual void	extendAddComponent (Component *subcomponent)
	Perform any secondary operations, e.g. More...

void	initComponentTreeTraversal (const Component &root) const
	Build the tree of Components from this component through its descendants. More...

virtual void	extendAddToSystemAfterSubcomponents (SimTK::MultibodySystem &system) const
	Add appropriate Simbody elements (if needed) to the System after your component's subcomponents have had a chance to add themselves to the system. More...

void	setStateVariableDerivativeValue (const SimTK::State &state, const std::string &name, double deriv) const
	Set the derivative of a state variable by name when computed inside of this Component's computeStateVariableDerivatives() method. More...

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

virtual void	extendRealizeModel (SimTK::State &state) const
	Obtain and name state resources (like state variables allocated by an underlying Simbody component) that may be needed, depending on modeling options. More...

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

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

virtual void	extendRealizePosition (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	extendRealizeVelocity (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	extendRealizeDynamics (const SimTK::State &state) const
	Perform computations (typically forces) that may depend on dynamics-stage state variables, and on computations performed in earlier stages (including velocity, position, and time), but not on other forces, accelerations, constraint multipliers, or reaction forces. More...

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

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

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

void	addStateVariable (Component::StateVariable *stateVariable) const
	The above method provides a convenient interface to this method, which automatically creates an 'AddedStateVariable' and allocates resources in the SimTK::State for this variable. More...

void	addDiscreteVariable (const std::string &discreteVariableName, SimTK::Stage invalidatesStage) const
	Add a system discrete variable belonging to this Component, 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 Component to hold calculated values that must be automatically invalidated when certain state values change. More...

SimTK::MultibodySystem &	updSystem () const
	Get writable reference to the MultibodySystem that this component is connected to. More...

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

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

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

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

template<typename T >
PropertyIndex	constructSocket (const std::string &name, const std::string &propertyComment)
	Construct a specialized Socket for this Component's dependence on another Component. More...

template<typename T , typename CompType = Component>
bool	constructOutput (const std::string &name, T(CompType::*const memFunc)(const SimTK::State &) const, const SimTK::Stage &dependsOn=SimTK::Stage::Acceleration)
	Construct an output for a member function of the same component. More...

template<typename T , typename CompType = Component>
bool	constructOutput (const std::string &name, const T &(CompType::*const memFunc)(const SimTK::State &) const, const SimTK::Stage &dependsOn=SimTK::Stage::Acceleration)
	This variant handles component member functions that return the output value by const reference (const T&). More...

template<typename T , typename CompType >
bool	constructListOutput (const std::string &name, T(CompType::*const memFunc)(const SimTK::State &, const std::string &channel) const, const SimTK::Stage &dependsOn=SimTK::Stage::Acceleration)
	Construct an output that can have multiple channels. More...

bool	constructOutputForStateVariable (const std::string &name)
	Construct an Output for a StateVariable. More...

template<typename T >
PropertyIndex	constructInput (const std::string &name, bool isList, const std::string &propertyComment, const SimTK::Stage &requiredAtStage=SimTK::Stage::Instance)
	Construct an Input (socket) for this Component's dependence on an Output signal. More...

void	setOwner (const Component &owner)
	Set this Component's reference to its owning Component 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)
	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	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...

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

void	makeObjectNamesConsistentWithProperties ()
	Make sure the name of an object is consistent with its property type. 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...

Static Protected Member Functions inherited from OpenSim::Component
static void	prependComponentPathToConnecteePath (Component &subcomponent)
	For internal use. More...

Protected Attributes inherited from OpenSim::ModelComponent
SimTK::ReferencePtr< Model >	_model
	The model this component belongs to. More...

Protected Attributes inherited from OpenSim::Object
PropertySet	_propertySet
	OBSOLETE: Property_Deprecated set for serializable member variables of this and derived classes. More...

Static Protected Attributes inherited from OpenSim::ModelComponent
static const SimTK::Vec3	InvalidScaleFactors
	Returned by getScaleFactors() if the ScaleSet does not contain scale factors for the base Body associated with the specified Frame. More...

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

Computes muscle activation using a modified version of the first-order dynamic models used by Thelen (2003) and Winters (1995).

The time derivative of activation ( \(da/dt\)) is calculated as follows:

\[ \frac{da}{dt} = \frac{u-a}{\tau(u,a)} \]

where \(u\) is excitation, \(a\) is activation, and \(\tau(u,a)\) is an excitation- and activation-dependent time constant:

\[ \tau(u,a) = \tau_{\rm{act}} (0.5 + 1.5a) \quad {\rm{if}}\ u > a \]

\[ \tau(u,a) = \tau_{\rm{deact}} / (0.5 + 1.5a) \quad {\rm{otherwise}} \]

Typical values for activation ( \(\tau_{\rm{act}}\)) and deactivation ( \(\tau_{\rm{deact}}\)) time constants are 10 ms and 40 ms, respectively.

Three properties are inherited from the base MuscleActivationDynamics class: minimum_activation, maximum_activation, and default_activation. Note that equilibrium muscle models typically have a numerical singularity in their state equations when activation is zero, so care should be taken when setting minimum_activation to zero. Minimum activation values between 0.01 and 0.1 are typically used with equilibrium muscle models.

Properties

activation_time_constant: Activation time constant (in seconds).
deactivation_time_constant: Deactivation time constant (in seconds).

Conditions

activation_time_constant > 0
deactivation_time_constant > 0

Default Property Values

activation_time_constant ...... 0.010
deactivation_time_constant .... 0.040
minimum_activation ............ 0.01
maximum_activation ............ 1
default_activation ............ 0.5

References

Thelen, D.G. (2003) Adjustment of muscle mechanics model parameters to simulate dynamic contractions in older adults. ASME Journal of Biomechanical Engineering 125(1):70–77.
Winters, J.M. (1995) An improved muscle-reflex actuator for use in large-scale neuromusculoskeletal models. Annals of Biomedical Engineering 23(4):359–374.

Author: Thomas Uchida, Matthew Millard, Ajay Seth

Member Typedef Documentation

◆ Self

typedef FirstOrderMuscleActivationDynamics OpenSim::FirstOrderMuscleActivationDynamics::Self

This typedef might be useful within the member functions of this class.

This is generated by the OpenSim_DECLARE_*_OBJECT macros.

◆ Super

typedef MuscleActivationDynamics OpenSim::FirstOrderMuscleActivationDynamics::Super

Use this typedef to refer to the superclass of this class.

Avoid using the explicit type name of the superclass; this would introduce bugs if the superclass is changed.

This is generated by the OpenSim_DECLARE_*_OBJECT macros.

Constructor & Destructor Documentation

◆ FirstOrderMuscleActivationDynamics() [1/2]

OpenSim::FirstOrderMuscleActivationDynamics::FirstOrderMuscleActivationDynamics ( )

Creates a first-order activation dynamic model with the default property values and assigns it a default name.

An ExcitationGetter must be created for obtaining muscle excitation.

◆ FirstOrderMuscleActivationDynamics() [2/2]

OpenSim::FirstOrderMuscleActivationDynamics::FirstOrderMuscleActivationDynamics	(	const std::string &	name,
		ExcitationGetter *	getter
	)

Creates a first-order activation dynamic model with the default property values, the specified name, and the specified ExcitationGetter.

Takes ownership of the ExcitationGetter object.

Member Function Documentation

◆ assign()

void OpenSim::FirstOrderMuscleActivationDynamics::assign ( Object & aObject )

inlineoverride

This allows copy assignment in the Java GUI.

Exceptions

Exception if the argument is not of type FirstOrderMuscleActivationDynamics.

◆ clone()

FirstOrderMuscleActivationDynamics* OpenSim::FirstOrderMuscleActivationDynamics::clone ( ) const

inlineoverridevirtual

Create a new heap-allocated copy of the concrete object to which this Object refers.

It is up to the caller to delete the returned object when no longer needed. Every concrete object deriving from Object implements this pure virtual method automatically, via the declaration macro it invokes (e.g., OpenSim_DECLARE_CONCRETE_OBJECT()). Note that the concrete class overrides modify the return type to be a pointer to the concrete object; that still overrides the base class method because the return type is covariant with (that is, derives from) Object.

Implements OpenSim::MuscleActivationDynamics.

◆ computeStateVariableDerivatives()

void OpenSim::FirstOrderMuscleActivationDynamics::computeStateVariableDerivatives ( const SimTK::State & s ) const

overridevirtual

Calculates the time derivative of activation using a first-order dynamic model.

Respects the lower bound on activation while preserving the expected steady-state value.

Reimplemented from OpenSim::Component.

◆ extendAddToSystem()

void OpenSim::FirstOrderMuscleActivationDynamics::extendAddToSystem ( SimTK::MultibodySystem & system ) const

overridevirtual

Adds activation to the state.

Reimplemented from OpenSim::Component.

◆ extendInitStateFromProperties()

void OpenSim::FirstOrderMuscleActivationDynamics::extendInitStateFromProperties ( SimTK::State & s ) const

overridevirtual

Initializes the activation state variable to default_activation.

Reimplemented from OpenSim::Component.

◆ extendSetPropertiesFromState()

void OpenSim::FirstOrderMuscleActivationDynamics::extendSetPropertiesFromState ( const SimTK::State & s )

overridevirtual

Sets default_activation to the current value of the activation state variable.

Reimplemented from OpenSim::Component.

◆ get_activation_time_constant()

const double& OpenSim::FirstOrderMuscleActivationDynamics::get_activation_time_constant ( ) const

inline

Get the value of the activation_time_constant property.

◆ get_deactivation_time_constant()

const double& OpenSim::FirstOrderMuscleActivationDynamics::get_deactivation_time_constant ( ) const

inline

Get the value of the deactivation_time_constant property.

◆ getActivation()

double OpenSim::FirstOrderMuscleActivationDynamics::getActivation ( const SimTK::State & s ) const

overridevirtual

Get the current activation from the state.

Implements OpenSim::MuscleActivationDynamics.

◆ getActivationTimeConstant()

double OpenSim::FirstOrderMuscleActivationDynamics::getActivationTimeConstant ( ) const

Get the activation time constant.

◆ getClassName()

static const std::string& OpenSim::FirstOrderMuscleActivationDynamics::getClassName ( )

inlinestatic

This returns "FirstOrderMuscleActivationDynamics".

See getConcreteClassName() if you want the class name of the underlying concrete object instead.

This is generated by the OpenSim_DECLARE_*_OBJECT macros.

◆ getConcreteClassName()

const std::string& OpenSim::FirstOrderMuscleActivationDynamics::getConcreteClassName ( ) const

inlineoverridevirtual

Returns the class name of the concrete Object-derived class of the actual object referenced by this Object, as a string.

This is the string that is used as the tag for this concrete object in an XML file. Every concrete class derived from Object automatically overrides this method via the declaration macro it uses. See getClassName() to get the class name of the referencing (possibly abstract) class rather than the concrete object.

See also: getClassName()

Implements OpenSim::MuscleActivationDynamics.

◆ getDeactivationTimeConstant()

double OpenSim::FirstOrderMuscleActivationDynamics::getDeactivationTimeConstant ( ) const

Get the deactivation time constant.

◆ safeDownCast()

static FirstOrderMuscleActivationDynamics* OpenSim::FirstOrderMuscleActivationDynamics::safeDownCast ( OpenSim::Object * obj )

inlinestatic

For use in MATLAB and Python to access the concrete class.

Example: cObj = FirstOrderMuscleActivationDynamics.safeDownCast(obj). This is equivalent to dynamic_cast<FirstOrderMuscleActivationDynamics*>(obj) in C++.

◆ set_activation_time_constant()

void OpenSim::FirstOrderMuscleActivationDynamics::set_activation_time_constant ( const double & value )

inline

Set the value of the activation_time_constant property.

◆ set_deactivation_time_constant()

void OpenSim::FirstOrderMuscleActivationDynamics::set_deactivation_time_constant ( const double & value )

inline

Set the value of the deactivation_time_constant property.

◆ setActivation()

void OpenSim::FirstOrderMuscleActivationDynamics::setActivation	(	SimTK::State &	s,
		double	activation
	)		const

overridevirtual

Set activation state variable to the value provided.

Implements OpenSim::MuscleActivationDynamics.

◆ setActivationTimeConstant()

void OpenSim::FirstOrderMuscleActivationDynamics::setActivationTimeConstant ( double activationTimeConstant )

Set the activation time constant to a value greater than zero.

◆ setDeactivationTimeConstant()

void OpenSim::FirstOrderMuscleActivationDynamics::setDeactivationTimeConstant ( double deactivationTimeConstant )

Set the deactivation time constant to a value greater than zero.

◆ upd_activation_time_constant()

double& OpenSim::FirstOrderMuscleActivationDynamics::upd_activation_time_constant ( )

inline

Get a writable reference to the activation_time_constant property.

◆ upd_deactivation_time_constant()

double& OpenSim::FirstOrderMuscleActivationDynamics::upd_deactivation_time_constant ( )

inline

Get a writable reference to the deactivation_time_constant property.

OpenSim Property, Socket, Output, Input Documentation

◆ activation_time_constant

double OpenSim::FirstOrderMuscleActivationDynamics::activation_time_constant

"Activation time constant (in seconds)"

This property appears in XML files under the tag <activation_time_constant>. This property was generated with the OpenSim_DECLARE_PROPERTY macro; see Property to learn about the property system.

See also: get_activation_time_constant(), upd_activation_time_constant(), set_activation_time_constant()

◆ deactivation_time_constant

double OpenSim::FirstOrderMuscleActivationDynamics::deactivation_time_constant

"Deactivation time constant (in seconds)"

This property appears in XML files under the tag <deactivation_time_constant>. This property was generated with the OpenSim_DECLARE_PROPERTY macro; see Property to learn about the property system.

See also: get_deactivation_time_constant(), upd_deactivation_time_constant(), set_deactivation_time_constant()

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

OpenSim/Actuators/FirstOrderMuscleActivationDynamics.h

OpenSim Properties, Sockets, Outputs, Inputs

Public Member Functions

Public Types

Auto-generated functions

Additional Inherited Members

Detailed Description

Member Typedef Documentation

◆ Self

◆ Super

Constructor & Destructor Documentation

◆ FirstOrderMuscleActivationDynamics() [1/2]

◆ FirstOrderMuscleActivationDynamics() [2/2]

Member Function Documentation

◆ assign()

◆ clone()

◆ computeStateVariableDerivatives()

◆ extendAddToSystem()

◆ extendInitStateFromProperties()

◆ extendSetPropertiesFromState()

◆ get_activation_time_constant()

◆ get_deactivation_time_constant()

◆ getActivation()

◆ getActivationTimeConstant()

◆ getClassName()

◆ getConcreteClassName()

◆ getDeactivationTimeConstant()

◆ safeDownCast()

◆ set_activation_time_constant()

◆ set_deactivation_time_constant()

◆ setActivation()

◆ setActivationTimeConstant()

◆ setDeactivationTimeConstant()

◆ upd_activation_time_constant()

◆ upd_deactivation_time_constant()

OpenSim Property, Socket, Output, Input Documentation

◆ activation_time_constant

◆ deactivation_time_constant