API  4.2 For C++ developers
OpenSim::InverseDynamicsSolver Class Reference

Solve for the generalized coordinate forces (1 per degree-of- freedom) that satisfy the unconstrained equations of motion given kinematics: q, u, u_dot. More...

Inheritance diagram for OpenSim::InverseDynamicsSolver:

## Public Member Functions

InverseDynamicsSolver (const Model &model)
Construct an InverseDynamics solver applied to the provided model. More...

virtual SimTK::Vector solve (const SimTK::State &s, const SimTK::Vector &udot=SimTK::Vector(0))
Solve the inverse dynamics system of equations for generalized coordinate forces, Tau. More...

virtual SimTK::Vector solve (const SimTK::State &s, const SimTK::Vector &udot, const SimTK::Vector &appliedMobilityForces, const SimTK::Vector_< SimTK::SpatialVec > &appliedBodyForces)
Solve the inverse dynamics system of equations for generalized coordinate forces, Tau. More...

virtual SimTK::Vector solve (SimTK::State &s, const FunctionSet &Qs, double time)
Solve the inverse dynamics system of equations for generalized coordinate forces, Tau. More...

virtual SimTK::Vector solve (SimTK::State &s, const FunctionSet &Qs, const std::vector< int > &coordinatesToSpeedsIndexMap, double time)
This is the same as above, but can be used when qdot != u. More...

virtual void solve (SimTK::State &s, const FunctionSet &Qs, const SimTK::Array_< double > &times, SimTK::Array_< SimTK::Vector > &genForceTrajectory)
Same as above but for a given time series populate an Array (trajectory) of generalized-coordinate forces (Vector). More...

virtual void solve (SimTK::State &s, const FunctionSet &Qs, const std::vector< int > coordinatesToSpeedsIndexMap, const SimTK::Array_< double > &times, SimTK::Array_< SimTK::Vector > &genForceTrajectory)
Same as above but for a given time series populate an Array (trajectory) of generalized-coordinate forces (Vector) that can be used when qdot != u. More...

Public Member Functions inherited from OpenSim::Solver
virtual ~Solver ()

Solver (const Model &model)

const ModelgetModel () const

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

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

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

AbstractPropertyupdPropertyByName (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...

virtual void updateFromXMLNode (SimTK::Xml::Element &objectElement, int versionNumber)
Use this method to deserialize an object from a SimTK::Xml::Element. 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...

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

const PropertySetgetPropertySet () const

## Public Types

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

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

Public Types inherited from OpenSim::Solver
typedef Solver 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...

## Auto-generated functions

static InverseDynamicsSolversafeDownCast (OpenSim::Object *obj)
For use in MATLAB and Python to access the concrete class. More...

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

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

InverseDynamicsSolverclone () 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...

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

static const std::string & getClassName ()
This returns "Solver". 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 ObjectgetDefaultInstanceOfType (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 ObjectnewInstanceOfType (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 ObjectmakeObjectFromFile (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 ObjectSafeCopy (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::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...

template<class T >
void checkPropertyValueIsPositive (const Property< T > &p) const
Throw an exception if any of the property's values are not positive. More...

template<class T >
void checkPropertyValueIsInSet (const Property< T > &p, const std::set< T > &set) const
Throw an exception if any of the property's values are not in the provided set. More...

template<class T >
void checkPropertyValueIsInRangeOrSet (const Property< T > &p, const T &lower, const T &upper, const std::set< T > &set) const
Throw an exception if any of the property's values are neither in the provided range nor in the provided set. 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 XMLDocumentgetDocument () const
Get a const pointer to the document (if any) associated with this object. More...

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

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

## Detailed Description

Solve for the generalized coordinate forces (1 per degree-of- freedom) that satisfy the unconstrained equations of motion given kinematics: q, u, u_dot.

The InverseDynamics equation: Tau = M*u_dot-G(q)-C(q,u)-A(q,u,t,x)

The InverseDynamicsSolver utilizes efficient methods in Simbody(TM) to compute the generalized forces, Tau, without explicitly forming the Mass matrix, M. System gravity, G, centrifugal and Coriolis, C, forces are computed internally. Caller provides q,u,t (supplied by the State), the desired u_dot and the applied loads, A. If applied loads are due to forces in the model, these loads are automatically computed and applied unless explicitly disabled in the model.

Version
1.0

## ◆ Self

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

This is generated by the OpenSim_DECLARE_*_OBJECT macros.

## ◆ 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.

## ◆ InverseDynamicsSolver()

 OpenSim::InverseDynamicsSolver::InverseDynamicsSolver ( const Model & model )

Construct an InverseDynamics solver applied to the provided model.

## ◆ assign()

 void OpenSim::InverseDynamicsSolver::assign ( Object & aObject )
inlineoverride

This allows copy assignment in the Java GUI.

Exceptions
 Exception if the argument is not of type InverseDynamicsSolver.

## ◆ clone()

 InverseDynamicsSolver* OpenSim::InverseDynamicsSolver::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::Solver.

## ◆ getClassName()

 static const std::string& OpenSim::InverseDynamicsSolver::getClassName ( )
inlinestatic

This returns "InverseDynamicsSolver".

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::InverseDynamicsSolver::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.

getClassName()

Implements OpenSim::Solver.

## ◆ safeDownCast()

 static InverseDynamicsSolver* OpenSim::InverseDynamicsSolver::safeDownCast ( OpenSim::Object * obj )
inlinestatic

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

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

## ◆ solve() [1/6]

 virtual SimTK::Vector OpenSim::InverseDynamicsSolver::solve ( const SimTK::State & s, const SimTK::Vector & udot = SimTK::Vector(0) )
virtual

Solve the inverse dynamics system of equations for generalized coordinate forces, Tau.

Applied loads are computed by the model according to the state.

Parameters
 [in] s the system state specifying time, coordinates and speeds [in] udot the vector of generalized accelerations in the order

## ◆ solve() [2/6]

 virtual SimTK::Vector OpenSim::InverseDynamicsSolver::solve ( const SimTK::State & s, const SimTK::Vector & udot, const SimTK::Vector & appliedMobilityForces, const SimTK::Vector_< SimTK::SpatialVec > & appliedBodyForces )
virtual

Solve the inverse dynamics system of equations for generalized coordinate forces, Tau.

Applied loads are explicitly provided as generalized coordinate forces (MobilityForces) and/or a Vector of Spatial-body forces

## ◆ solve() [3/6]

 virtual SimTK::Vector OpenSim::InverseDynamicsSolver::solve ( SimTK::State & s, const FunctionSet & Qs, double time )
virtual

Solve the inverse dynamics system of equations for generalized coordinate forces, Tau.

Now the state is updated from known coordinates, q, as functions of time. Coordinate functions must be twice differentiable and are used to supply the coordinate speed and acceleration. Coordinate functions must be in the same order as the order of q's, u's, and udot's in the provided SimTK::State. NOTE: forces with internal states should be removed/disabled prior to solving if default state is inappropriate

## ◆ solve() [4/6]

 virtual SimTK::Vector OpenSim::InverseDynamicsSolver::solve ( SimTK::State & s, const FunctionSet & Qs, const std::vector< int > & coordinatesToSpeedsIndexMap, double time )
virtual

This is the same as above, but can be used when qdot != u.

This adds an extra vector, coordinatesToSpeedsIndexMap, which is the length of number of u's in the SimTK::State, and whose i'th index is the index of the FunctionSet Qs from which each 'u' and 'udot' will be calculated.

## ◆ solve() [5/6]

 virtual void OpenSim::InverseDynamicsSolver::solve ( SimTK::State & s, const FunctionSet & Qs, const SimTK::Array_< double > & times, SimTK::Array_< SimTK::Vector > & genForceTrajectory )
virtual

Same as above but for a given time series populate an Array (trajectory) of generalized-coordinate forces (Vector).

Coordinate functions must be in the same order as the order of q's, u's, and udot's in the provided SimTK::State.

## ◆ solve() [6/6]

 virtual void OpenSim::InverseDynamicsSolver::solve ( SimTK::State & s, const FunctionSet & Qs, const std::vector< int > coordinatesToSpeedsIndexMap, const SimTK::Array_< double > & times, SimTK::Array_< SimTK::Vector > & genForceTrajectory )
virtual

Same as above but for a given time series populate an Array (trajectory) of generalized-coordinate forces (Vector) that can be used when qdot != u.

This adds an extra vector, coordinatesToSpeedsIndexMap, which is the length of number of u's in the SimTK::State, and whose i'th index is the index of the FunctionSet Qs from which each 'u' and 'udot' will be calculated.

The documentation for this class was generated from the following file:
• OpenSim/Simulation/InverseDynamicsSolver.h