This is a muscle modeling utility class containing kinematic equations that describe the deformation of muscle fibers as they change length using a fixed-width-parallelogram pennation model. More...

Inheritance diagram for OpenSim::MuscleFixedWidthPennationModel:

OpenSim Properties, Sockets, Outputs, Inputs
Properties (single-value)
double	optimal_fiber_length
	"Optimal length of the muscle fibers, in meters (overridden when this is a subcomponent of a Muscle)" More...

double	pennation_angle_at_optimal
	"Angle between tendon and fibers at optimal fiber length, in radians (overridden when this is a subcomponent of a Muscle)" More...

double	maximum_pennation_angle
	"Maximum pennation angle, in radians (overridden when this is a subcomponent of a Muscle)" 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
	MuscleFixedWidthPennationModel ()
	The default constructor creates a fixed-width-parallelogram pennation model with the default property values. More...

	MuscleFixedWidthPennationModel (double optimalFiberLength, double optimalPennationAngle, double maximumPennationAngle)
	Creates a fixed-width-parallelogram pennation model using the provided parameters. More...

double	getParallelogramHeight () const

double	getMinimumFiberLength () const

double	getMinimumFiberLengthAlongTendon () const

double	calcPennationAngle (double fiberLength) const
	Calculates the pennation angle (the orientation of the parallelogram) given the fiber length. More...

double	calcTendonLength (double cosPennationAngle, double fiberLength, double muscleLength) const
	Calculates the length of the tendon given the cosine of the pennation angle, the length of the fiber, and the length of the entire musculotendon actuator. More...

double	calcFiberLengthAlongTendon (double fiberLength, double cosPennationAngle) const
	Calculates the length of the fiber projected onto the axis of the tendon. More...

double	calcPennationAngularVelocity (double tanPennationAngle, double fiberLength, double fiberVelocity) const
	Calculates the angular velocity of the parallelogram (i.e., the time derivative of the pennation angle. More...

double	calcTendonVelocity (double cosPennationAngle, double sinPennationAngle, double pennationAngularVelocity, double fiberLength, double fiberVelocity, double muscleVelocity) const
	More...

double	calcFiberVelocityAlongTendon (double fiberLength, double fiberVelocity, double sinPennationAngle, double cosPennationAngle, double pennationAngularVelocity) const
	More...

double	calcPennationAngularAcceleration (double fiberLength, double fiberVelocity, double fiberAcceleration, double sinPennationAngle, double cosPennationAngle, double pennationAngularVelocity) const
	More...

double	calcFiberAccelerationAlongTendon (double fiberLength, double fiberVelocity, double fiberAcceleration, double sinPennationAngle, double cosPennationAngle, double pennationAngularVelocity, double pennationAngularAcceleration) const
	More...

double	calc_DFiberLengthAlongTendon_DfiberLength (double fiberLength, double sinPennationAngle, double cosPennationAngle, double DpennationAngle_DfiberLength) const
	Calculates the partial derivative of the fiber length along the tendon with respect to the fiber length. More...

double	calc_DPennationAngularVelocity_DfiberLength (double fiberLength, double fiberVelocity, double sinPennationAngle, double cosPennationAngle, double pennationAngularVelocity, double DpennationAngle_DfiberLength) const
	Calculates the partial derivative of the pennation angular velocity with respect to the fiber length. More...

double	calc_DFiberVelocityAlongTendon_DfiberLength (double fiberLength, double fiberVelocity, double sinPennationAngle, double cosPennationAngle, double pennationAngularVelocity, double DpennationAngle_DfiberLength, double DpennationAngularVelocity_DfiberLength) const
	Calculates the partial derivative of the fiber velocity along the tendon with respect to the fiber length. More...

double	calc_DPennationAngle_DfiberLength (double fiberLength) const
	Calculates the partial derivative of the pennation angle with respect to the fiber length. More...

double	calc_DTendonLength_DfiberLength (double fiberLength, double sinPennationAngle, double cosPennationAngle, double DpennationAngle_DfiberLength) const
	Calculates the partial derivative of the tendon length with respect to the fiber length. More...

double	calcFiberLength (double muscleLength, double tendonLength) const
	More...

double	calcFiberVelocity (double cosPennationAngle, double muscleVelocity, double tendonVelocity) const
	More...

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

double &	upd_optimal_fiber_length ()
	Get a writable reference to the optimal_fiber_length property. More...

void	set_optimal_fiber_length (const double &value)
	Set the value of the optimal_fiber_length property. More...

const double &	get_pennation_angle_at_optimal () const
	Get the value of the pennation_angle_at_optimal property. More...

double &	upd_pennation_angle_at_optimal ()
	Get a writable reference to the pennation_angle_at_optimal property. More...

void	set_pennation_angle_at_optimal (const double &value)
	Set the value of the pennation_angle_at_optimal property. More...

const double &	get_maximum_pennation_angle () const
	Get the value of the maximum_pennation_angle property. More...

double &	upd_maximum_pennation_angle ()
	Get a writable reference to the maximum_pennation_angle property. More...

void	set_maximum_pennation_angle (const double &value)
	Set the value of the maximum_pennation_angle property. 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...

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...

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...

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...

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<class T >
SimTK::CacheEntryIndex	getCacheVariableIndex (const CacheVariable< T > &cv) const
	Get the index of a Component's cache variable in the Subsystem for allocations. More...

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

template<class 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<class T >
const T &	getCacheVariableValue (const SimTK::State &state, const CacheVariable< T > &cv) const
	Get the value of a cache variable allocated by this Component. More...

template<typename T >
void	setCacheVariableValue (const SimTK::State &state, const std::string &k, T value) const
	Set the value of a cache variable, identified by `name`, to a new value and mark the cache variable as valid. More...

template<typename T >
void	setCacheVariableValue (const SimTK::State &state, const CacheVariable< T > &cv, T value) const
	Set the value of a cache variable to a new value and mark the cache variable as valid. More...

template<typename T >
T &	updCacheVariableValue (const SimTK::State &state, const std::string &name) const
	Returns a mutable reference to the value of a cache variable identified by `name`. More...

template<typename T >
T &	updCacheVariableValue (const SimTK::State &state, const CacheVariable< T > &cv) const
	Returns a mutable reference to the value of a cache variable. More...

bool	isCacheVariableValid (const SimTK::State &state, const std::string &name) const
	Returns true if the cache variable, identified by `name`, is valid. More...

template<class T >
bool	isCacheVariableValid (const SimTK::State &state, const CacheVariable< T > &cv) const
	Returns true if the cache variable is valid. More...

void	markCacheVariableValid (const SimTK::State &state, const std::string &name) const
	Marks the value of a cache variable, identified by `name`, as valid. More...

template<typename T >
void	markCacheVariableValid (const SimTK::State &state, const CacheVariable< T > &cv) const
	Marks the value of a cache variable as valid. More...

void	markCacheVariableInvalid (const SimTK::State &state, const std::string &name) const
	Marks the value of a cache variable, identified by `name`, as invalid. More...

template<class T >
void	markCacheVariableInvalid (const SimTK::State &state, const CacheVariable< T > &cv) const
	Marks the value of a cache variable as invalid. 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 () const
	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

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

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

MuscleFixedWidthPennationModel *	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::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 amount of logging output. More...

static int	getDebugLevel ()
	Get the 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...

Detailed Description

This is a muscle modeling utility class containing kinematic equations that describe the deformation of muscle fibers as they change length using a fixed-width-parallelogram pennation model.

This pennation model makes several assumptions:

Fibers are straight, parallel, of equal length, and coplanar.
The area and height of the parallelogram remains constant.

The parallelogram maintains a constant area and height by shearing as the muscle fibers change length, as shown in the figure below. The constant-area assumption is intended to mimic the constant-volume property of incompressible biological muscle. For details, please refer to Zajac (1989) and Millard et al. (2013).

Parameters

optimalFiberLength	The optimal length of the muscle fibers (meters).
optimalPennationAngle	The angle between the tendon and fibers at optimal fiber length (radians).
maximumPennationAngle	The maximum pennation angle permitted (radians). This parameter is particularly useful for avoiding a pennation angle singularity at Pi/2 radians.

Conditions

optimalFiberLength > 0
0 <= optimalPennationAngle < Pi/2
0 <= maximumPennationAngle <= Pi/2

Default Parameter Values

optimalFiberLength ....... 0.1
optimalPennationAngle .... 0.0
maximumPennationAngle .... acos(0.1) = 84.3 degrees

Example

double optFibLen = 0.1;
double optPenAng = SimTK::Pi/4.0;
double maxPenAng = acos(0.001);
MuscleFixedWidthPennationModel fibKin = MuscleFixedWidthPennationModel(optFibLen, optPenAng, maxPenAng);

Note that this object should be updated through the set methods provided. These set methods will take care of rebuilding the object correctly. If you modify the properties directly, the object will not be rebuilt, and upon calling any function, an exception will be thrown because the object is out-of-date with its properties.

References

Zajac, F.E. (1989) Muscle and tendon: properties, models, scaling, and application to biomechanics and motor control. Critical Reviews in Biomedical Engineering 17(4):359–411.
Millard, M., Uchida, T., Seth, A., Delp, S.L. (2013) Flexing computational muscle: modeling and simulation of musculotendon dynamics. ASME Journal of Biomechanical Engineering 135(2):021005. http://dx.doi.org/10.1115/1.4023390.

Author: Matt Millard

Constructor & Destructor Documentation

◆ MuscleFixedWidthPennationModel() [1/2]

OpenSim::MuscleFixedWidthPennationModel::MuscleFixedWidthPennationModel ( )

The default constructor creates a fixed-width-parallelogram pennation model with the default property values.

◆ MuscleFixedWidthPennationModel() [2/2]

OpenSim::MuscleFixedWidthPennationModel::MuscleFixedWidthPennationModel	(	double	optimalFiberLength,
		double	optimalPennationAngle,
		double	maximumPennationAngle
	)

Creates a fixed-width-parallelogram pennation model using the provided parameters.

Member Function Documentation

◆ calc_DFiberLengthAlongTendon_DfiberLength()

double OpenSim::MuscleFixedWidthPennationModel::calc_DFiberLengthAlongTendon_DfiberLength	(	double	fiberLength,
		double	sinPennationAngle,
		double	cosPennationAngle,
		double	DpennationAngle_DfiberLength
	)		const

Calculates the partial derivative of the fiber length along the tendon with respect to the fiber length.

◆ calc_DFiberVelocityAlongTendon_DfiberLength()

double OpenSim::MuscleFixedWidthPennationModel::calc_DFiberVelocityAlongTendon_DfiberLength	(	double	fiberLength,
		double	fiberVelocity,
		double	sinPennationAngle,
		double	cosPennationAngle,
		double	pennationAngularVelocity,
		double	DpennationAngle_DfiberLength,
		double	DpennationAngularVelocity_DfiberLength
	)		const

Calculates the partial derivative of the fiber velocity along the tendon with respect to the fiber length.

◆ calc_DPennationAngle_DfiberLength()

double OpenSim::MuscleFixedWidthPennationModel::calc_DPennationAngle_DfiberLength ( double fiberLength ) const

Calculates the partial derivative of the pennation angle with respect to the fiber length.

◆ calc_DPennationAngularVelocity_DfiberLength()

double OpenSim::MuscleFixedWidthPennationModel::calc_DPennationAngularVelocity_DfiberLength	(	double	fiberLength,
		double	fiberVelocity,
		double	sinPennationAngle,
		double	cosPennationAngle,
		double	pennationAngularVelocity,
		double	DpennationAngle_DfiberLength
	)		const

Calculates the partial derivative of the pennation angular velocity with respect to the fiber length.

◆ calc_DTendonLength_DfiberLength()

double OpenSim::MuscleFixedWidthPennationModel::calc_DTendonLength_DfiberLength	(	double	fiberLength,
		double	sinPennationAngle,
		double	cosPennationAngle,
		double	DpennationAngle_DfiberLength
	)		const

Calculates the partial derivative of the tendon length with respect to the fiber length.

◆ calcFiberAccelerationAlongTendon()

double OpenSim::MuscleFixedWidthPennationModel::calcFiberAccelerationAlongTendon	(	double	fiberLength,
		double	fiberVelocity,
		double	fiberAcceleration,
		double	sinPennationAngle,
		double	cosPennationAngle,
		double	pennationAngularVelocity,
		double	pennationAngularAcceleration
	)		const

Parameters

fiberLength	The length of the fiber (m).
fiberVelocity	The lengthening velocity of the fiber (m/s).
fiberAcceleration	The lengthening acceleration of the fiber (m/s^2).
sinPennationAngle	The sine of the pennation angle.
cosPennationAngle	The cosine of the pennation angle.
pennationAngularVelocity	The angular velocity of the parallelogram (rad/s).
pennationAngularAcceleration	The angular acceleration of the parallelogram (rad/s^2).

Returns: The acceleration of the fiber projected onto the axis of the tendon (m/s^2).

◆ calcFiberLength()

double OpenSim::MuscleFixedWidthPennationModel::calcFiberLength	(	double	muscleLength,
		double	tendonLength
	)		const

Parameters

muscleLength	The length of the musculotendon actuator (m).
tendonLength	The length of the tendon (m).

Returns: The length of the fiber (m).

◆ calcFiberLengthAlongTendon()

double OpenSim::MuscleFixedWidthPennationModel::calcFiberLengthAlongTendon	(	double	fiberLength,
		double	cosPennationAngle
	)		const

Calculates the length of the fiber projected onto the axis of the tendon.

◆ calcFiberVelocity()

double OpenSim::MuscleFixedWidthPennationModel::calcFiberVelocity	(	double	cosPennationAngle,
		double	muscleVelocity,
		double	tendonVelocity
	)		const

Parameters

cosPennationAngle	The cosine of the pennation angle.
muscleVelocity	The lengthening velocity of the musculotendon actuator (m/s).
tendonVelocity	The lengthening velocity of the tendon (m/s).

Returns: The lengthening velocity of the fiber (m/s).

◆ calcFiberVelocityAlongTendon()

double OpenSim::MuscleFixedWidthPennationModel::calcFiberVelocityAlongTendon	(	double	fiberLength,
		double	fiberVelocity,
		double	sinPennationAngle,
		double	cosPennationAngle,
		double	pennationAngularVelocity
	)		const

Parameters

fiberLength	The length of the fiber (m).
fiberVelocity	The lengthening velocity of the fiber (m/s).
sinPennationAngle	The sine of the pennation angle.
cosPennationAngle	The cosine of the pennation angle.
pennationAngularVelocity	The angular velocity of the parallelogram (rad/s).

Returns: The lengthening velocity of the fiber projected onto the axis of the tendon (m/s).

◆ calcPennationAngle()

double OpenSim::MuscleFixedWidthPennationModel::calcPennationAngle ( double fiberLength ) const

Calculates the pennation angle (the orientation of the parallelogram) given the fiber length.

◆ calcPennationAngularAcceleration()

double OpenSim::MuscleFixedWidthPennationModel::calcPennationAngularAcceleration	(	double	fiberLength,
		double	fiberVelocity,
		double	fiberAcceleration,
		double	sinPennationAngle,
		double	cosPennationAngle,
		double	pennationAngularVelocity
	)		const

Parameters

fiberLength	The length of the fiber (m).
fiberVelocity	The lengthening velocity of the fiber (m/s).
fiberAcceleration	The lengthening acceleration of the fiber (m/s^2).
sinPennationAngle	The sine of the pennation angle.
cosPennationAngle	The cosine of the pennation angle.
pennationAngularVelocity	The angular velocity of the parallelogram (rad/s).

Returns: The angular acceleration of the parallelogram (rad/s^2).

◆ calcPennationAngularVelocity()

double OpenSim::MuscleFixedWidthPennationModel::calcPennationAngularVelocity	(	double	tanPennationAngle,
		double	fiberLength,
		double	fiberVelocity
	)		const

Calculates the angular velocity of the parallelogram (i.e., the time derivative of the pennation angle.

Parameters

tanPennationAngle	The tangent of the pennation angle.
fiberLength	The length of the fiber (m).
fiberVelocity	The lengthening velocity of the fiber (m/s).

Returns: The angular velocity of the parallelogram (rad/s).

◆ calcTendonLength()

double OpenSim::MuscleFixedWidthPennationModel::calcTendonLength	(	double	cosPennationAngle,
		double	fiberLength,
		double	muscleLength
	)		const

Calculates the length of the tendon given the cosine of the pennation angle, the length of the fiber, and the length of the entire musculotendon actuator.

◆ calcTendonVelocity()

double OpenSim::MuscleFixedWidthPennationModel::calcTendonVelocity	(	double	cosPennationAngle,
		double	sinPennationAngle,
		double	pennationAngularVelocity,
		double	fiberLength,
		double	fiberVelocity,
		double	muscleVelocity
	)		const

Parameters

cosPennationAngle	The cosine of the pennation angle.
sinPennationAngle	The sine of the pennation angle.
pennationAngularVelocity	The angular velocity of the parallelogram (rad/s).
fiberLength	The length of the fiber (m).
fiberVelocity	The lengthening velocity of the fiber (m/s).
muscleVelocity	The lengthening velocity of the muscle path (m/s).

Returns: The lengthening velocity of the tendon (m/s).

◆ clone()

MuscleFixedWidthPennationModel* OpenSim::MuscleFixedWidthPennationModel::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::ModelComponent.

◆ extendFinalizeFromProperties()

void OpenSim::MuscleFixedWidthPennationModel::extendFinalizeFromProperties ( )

overrideprotectedvirtual

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.

For example, each property should be checked to ensure that its value is within an acceptable range. When this method returns, the component will be marked as being up-to-date with its properties. Do not perform any configuration that depends on the SimTK::MultibodySystem; it is not available at this point.

If you override this method, be sure to invoke the base class method first, using code like this:

void MyComponent::extendFinalizeFromProperties() {
    Super::extendFinalizeFromProperties(); // invoke parent class method
    // ... your code goes here
    // ... catch invalid property values
    // ... initialize any internal data structures
}

Reimplemented from OpenSim::Component.

◆ get_maximum_pennation_angle()

const double& OpenSim::MuscleFixedWidthPennationModel::get_maximum_pennation_angle ( ) const

inline

Get the value of the maximum_pennation_angle property.

◆ get_optimal_fiber_length()

const double& OpenSim::MuscleFixedWidthPennationModel::get_optimal_fiber_length ( ) const

inline

Get the value of the optimal_fiber_length property.

◆ get_pennation_angle_at_optimal()

const double& OpenSim::MuscleFixedWidthPennationModel::get_pennation_angle_at_optimal ( ) const

inline

Get the value of the pennation_angle_at_optimal property.

◆ getClassName()

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

inlinestatic

This returns "MuscleFixedWidthPennationModel".

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

◆ getConcreteClassName()

const std::string& OpenSim::MuscleFixedWidthPennationModel::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::ModelComponent.

◆ getMinimumFiberLength()

double OpenSim::MuscleFixedWidthPennationModel::getMinimumFiberLength ( ) const

Returns: The minimum possible fiber length.

◆ getMinimumFiberLengthAlongTendon()

double OpenSim::MuscleFixedWidthPennationModel::getMinimumFiberLengthAlongTendon ( ) const

Returns: The minimum possible fiber length along the tendon.

◆ getParallelogramHeight()

double OpenSim::MuscleFixedWidthPennationModel::getParallelogramHeight ( ) const

Returns: The height of the fixed-width parallelogram.

◆ safeDownCast()

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

inlinestatic

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

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

◆ set_maximum_pennation_angle()

void OpenSim::MuscleFixedWidthPennationModel::set_maximum_pennation_angle ( const double & value )

inline

Set the value of the maximum_pennation_angle property.

◆ set_optimal_fiber_length()

void OpenSim::MuscleFixedWidthPennationModel::set_optimal_fiber_length ( const double & value )

inline

Set the value of the optimal_fiber_length property.

◆ set_pennation_angle_at_optimal()

void OpenSim::MuscleFixedWidthPennationModel::set_pennation_angle_at_optimal ( const double & value )

inline

Set the value of the pennation_angle_at_optimal property.

◆ upd_maximum_pennation_angle()

double& OpenSim::MuscleFixedWidthPennationModel::upd_maximum_pennation_angle ( )

inline

Get a writable reference to the maximum_pennation_angle property.

◆ upd_optimal_fiber_length()

double& OpenSim::MuscleFixedWidthPennationModel::upd_optimal_fiber_length ( )

inline

Get a writable reference to the optimal_fiber_length property.

◆ upd_pennation_angle_at_optimal()

double& OpenSim::MuscleFixedWidthPennationModel::upd_pennation_angle_at_optimal ( )

inline

Get a writable reference to the pennation_angle_at_optimal property.

OpenSim Property, Socket, Output, Input Documentation

◆ maximum_pennation_angle

double OpenSim::MuscleFixedWidthPennationModel::maximum_pennation_angle

"Maximum pennation angle, in radians (overridden when this is a subcomponent of a Muscle)"

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

See also: get_maximum_pennation_angle(), upd_maximum_pennation_angle(), set_maximum_pennation_angle()

◆ optimal_fiber_length

double OpenSim::MuscleFixedWidthPennationModel::optimal_fiber_length

"Optimal length of the muscle fibers, in meters (overridden when this is a subcomponent of a Muscle)"

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

See also: get_optimal_fiber_length(), upd_optimal_fiber_length(), set_optimal_fiber_length()

◆ pennation_angle_at_optimal

double OpenSim::MuscleFixedWidthPennationModel::pennation_angle_at_optimal

"Angle between tendon and fibers at optimal fiber length, in radians (overridden when this is a subcomponent of a Muscle)"

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

See also: get_pennation_angle_at_optimal(), upd_pennation_angle_at_optimal(), set_pennation_angle_at_optimal()

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

OpenSim/Actuators/MuscleFixedWidthPennationModel.h

OpenSim Properties, Sockets, Outputs, Inputs

Public Member Functions

Auto-generated functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ MuscleFixedWidthPennationModel() [1/2]

◆ MuscleFixedWidthPennationModel() [2/2]

Member Function Documentation

◆ calc_DFiberLengthAlongTendon_DfiberLength()

◆ calc_DFiberVelocityAlongTendon_DfiberLength()

◆ calc_DPennationAngle_DfiberLength()

◆ calc_DPennationAngularVelocity_DfiberLength()

◆ calc_DTendonLength_DfiberLength()

◆ calcFiberAccelerationAlongTendon()

◆ calcFiberLength()

◆ calcFiberLengthAlongTendon()

◆ calcFiberVelocity()

◆ calcFiberVelocityAlongTendon()

◆ calcPennationAngle()

◆ calcPennationAngularAcceleration()

◆ calcPennationAngularVelocity()

◆ calcTendonLength()

◆ calcTendonVelocity()

◆ clone()

◆ extendFinalizeFromProperties()

◆ get_maximum_pennation_angle()

◆ get_optimal_fiber_length()

◆ get_pennation_angle_at_optimal()

◆ getClassName()

◆ getConcreteClassName()

◆ getMinimumFiberLength()

◆ getMinimumFiberLengthAlongTendon()

◆ getParallelogramHeight()

◆ safeDownCast()

◆ set_maximum_pennation_angle()

◆ set_optimal_fiber_length()

◆ set_pennation_angle_at_optimal()

◆ upd_maximum_pennation_angle()

◆ upd_optimal_fiber_length()

◆ upd_pennation_angle_at_optimal()

OpenSim Property, Socket, Output, Input Documentation

◆ maximum_pennation_angle

◆ optimal_fiber_length

◆ pennation_angle_at_optimal