API  4.1
For C++ developers
OpenSim::Force Class Referenceabstract

This abstract class represents a force applied to bodies or generalized coordinates during a simulation. More...

+ Inheritance diagram for OpenSim::Force:

OpenSim Properties, Sockets, Outputs, Inputs

Properties (single-value)
bool appliesForce
 "Flag indicating whether the force is applied or not. If true the force" "is applied to the MultibodySystem otherwise the force is not applied." "NOTE: Prior to OpenSim 4.0, this behavior was controlled by the " "'isDisabled' property, where 'true' meant that force was not being " "applied. Thus, if 'isDisabled' is true, then 'appliesForce` is false." More...
 
Outputs
double potential_energy
 Provides the value of computePotentialEnergy() and is available at stage SimTK::Stage::Velocity . 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

virtual bool shouldBeParallelized () const
 Tell SimBody to parallelize this force. More...
 
bool appliesForce (const SimTK::State &s) const
 Return if the Force is applied (or enabled) or not. More...
 
void setAppliesForce (SimTK::State &s, bool applyForce) const
 Set whether or not the Force is applied. More...
 
virtual OpenSim::Array< std::string > getRecordLabels () const
 Methods to query a Force for the value actually applied during simulation. More...
 
virtual OpenSim::Array< double > getRecordValues (const SimTK::State &state) const
 Given SimTK::State object extract all the values necessary to report forces, application location frame, etc. More...
 
virtual bool hasGeometryPath () const
 Return a flag indicating whether the Force is applied along a Path. More...
 
Property-related functions
const bool & get_appliesForce () const
 Get the value of the appliesForce property. More...
 
bool & upd_appliesForce ()
 Get a writable reference to the appliesForce property. More...
 
void set_appliesForce (const bool &value)
 Set the value of the appliesForce 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 ModelgetModel () const
 Get a const reference to the Model this component is part of. More...
 
ModelupdModel ()
 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...
 
Componentoperator= (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 ComponentgetComponent (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)
 
ComponentupdComponent (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 StateVariabletraverseToStateVariable (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 ObjectgetConnectee (const std::string &name) const
 Get the connectee as an Object. More...
 
const AbstractSocketgetSocket (const std::string &name) const
 Get an AbstractSocket for the given socket name. More...
 
AbstractSocketupdSocket (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 AbstractInputgetInput (const std::string &name) const
 Get an Input provided by this Component by name. More...
 
AbstractInputupdInput (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 AbstractOutputgetOutput (const std::string &name) const
 Get the Output provided by this Component by name. More...
 
AbstractOutputupdOutput (const std::string &name)
 Get a writable reference to an Output provided by this Component by name. More...
 
SimTK::IteratorRange< OutputConstIteratorgetOutputs () const
 Iterate through all Outputs of this component. More...
 
const ComponentgetOwner () const
 Access the owner of this Component. More...
 
bool hasOwner () const
 (For advanced users) Check if this Component has an owner. More...
 
const ComponentgetRoot () 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...
 
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...
 
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 Force 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...
 

Protected Member Functions

 Force ()
 Default constructor sets up Force-level properties; can only be called from a derived class constructor. More...
 
 Force (SimTK::Xml::Element &node)
 Deserialization from XML, necessary so that derived classes can (de)serialize. More...
 
void extendInitStateFromProperties (SimTK::State &state) const override
 Subclass should override; be sure to invoke Super::extendInitStateFromProperties() at the beginning of the overriding method. More...
 
void extendAddToSystem (SimTK::MultibodySystem &system) const override
 Default is to create a ForceAdapter which is a SimTK::Force::Custom as the underlying computational component. More...
 
void extendSetPropertiesFromState (const SimTK::State &state) override
 Subclass should override; be sure to invoke Force::extendSetPropertiesFromState() at the beginning of the overriding method. More...
 
virtual void computeForce (const SimTK::State &state, SimTK::Vector_< SimTK::SpatialVec > &bodyForces, SimTK::Vector &generalizedForces) const
 Subclasses must implement this method to compute the forces that should be applied to bodies and generalized speeds. More...
 
virtual double computePotentialEnergy (const SimTK::State &state) const
 Subclasses may optionally override this method to compute a contribution to the potential energy of the system. More...
 
void applyForceToPoint (const SimTK::State &state, const PhysicalFrame &body, const SimTK::Vec3 &point, const SimTK::Vec3 &force, SimTK::Vector_< SimTK::SpatialVec > &bodyForces) const
 Apply a force at a particular point (a "station") on a given body. More...
 
void applyTorque (const SimTK::State &state, const PhysicalFrame &body, const SimTK::Vec3 &torque, SimTK::Vector_< SimTK::SpatialVec > &bodyForces) const
 Apply a torque to a particular body. More...
 
void applyGeneralizedForce (const SimTK::State &state, const Coordinate &coord, double force, SimTK::Vector &generalizedForces) const
 Apply a generalized force. More...
 
void updateFromXMLNode (SimTK::Xml::Element &node, int versionNumber) override
 Handle a change in XML syntax for Sockets. 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 Componentget_components (int i) const
 Get the value of the i-th element of the components property. More...
 
Componentupd_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...
 
virtual void computeStateVariableDerivatives (const SimTK::State &s) const
 If a model component has allocated any continuous state variables using the addStateVariable() method, then computeStateVariableDerivatives() must be implemented to provide time derivatives for those states. More...
 
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 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

SimTK::ResetOnCopy< SimTK::ForceIndex > _index
 ID for the force in Simbody. 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...
 

Friends

class ForceAdapter
 

Auto-generated functions

static ForcesafeDownCast (OpenSim::Object *obj)
 For use in MATLAB and Python to access the concrete class. More...
 
static const std::string & getClassName ()
 This returns "Force". More...
 
void assign (Object &aObject) override
 This allows copy assignment in the Java GUI. More...
 
Forceclone () const override=0
 Create a new heap-allocated copy of the concrete object to which this Object refers. More...
 
const std::string & getConcreteClassName () const override=0
 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 ModelComponentsafeDownCast (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 ComponentsafeDownCast (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 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 debug level to get verbose output. More...
 
static int getDebugLevel ()
 Get 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...
 
- Static Protected Member Functions inherited from OpenSim::Component
static void prependComponentPathToConnecteePath (Component &subcomponent)
 For internal use. 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...
 

Detailed Description

This abstract class represents a force applied to bodies or generalized coordinates during a simulation.

Each subclass represents a different type of force. The actual force computation is done by a SimTK::Force, which is created by extendAddToSystem().

Author
Peter Eastman
Ajay Seth

Member Typedef Documentation

◆ 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.

Constructor & Destructor Documentation

◆ Force() [1/2]

OpenSim::Force::Force ( )
protected

Default constructor sets up Force-level properties; can only be called from a derived class constructor.

◆ Force() [2/2]

OpenSim::Force::Force ( SimTK::Xml::Element &  node)
inlineprotected

Deserialization from XML, necessary so that derived classes can (de)serialize.

Member Function Documentation

◆ appliesForce()

bool OpenSim::Force::appliesForce ( const SimTK::State &  s) const

Return if the Force is applied (or enabled) or not.

◆ applyForceToPoint()

void OpenSim::Force::applyForceToPoint ( const SimTK::State &  state,
const PhysicalFrame body,
const SimTK::Vec3 &  point,
const SimTK::Vec3 &  force,
SimTK::Vector_< SimTK::SpatialVec > &  bodyForces 
) const
protected

Apply a force at a particular point (a "station") on a given body.

Note that the point Vec3(0) is the body origin, not necessarily the center of mass whose location is maintained relative to the body origin. Although this applies a pure force to the given point, that will also result in a torque acting on the body when looking at the resultant at some other point.

This method may only be called from inside computeForce(). Invoking it at any other time will produce an exception.

Parameters
statestate used only to determine which element of bodyForces to modify
bodythe body to apply the force to
pointthe point at which to apply the force, specified in the body's frame
forcethe force to apply, specified in the inertial (ground) reference frame
bodyForcesthe set of system bodyForces to which this force is added

◆ applyGeneralizedForce()

void OpenSim::Force::applyGeneralizedForce ( const SimTK::State &  state,
const Coordinate coord,
double  force,
SimTK::Vector &  generalizedForces 
) const
protected

Apply a generalized force.

This method may only be called from inside computeForce(). Invoking it at any other time will produce an exception.

Parameters
statestate used only to determine which element of generalizedForces to modify
coordthe generalized coordinate to which the force should be applied
forcethe (scalar) force to apply
generalizedForcesthe set of system generalizedForces to which the force is to be added

◆ applyTorque()

void OpenSim::Force::applyTorque ( const SimTK::State &  state,
const PhysicalFrame body,
const SimTK::Vec3 &  torque,
SimTK::Vector_< SimTK::SpatialVec > &  bodyForces 
) const
protected

Apply a torque to a particular body.

This method may only be called from inside computeForce(). Invoking it at any other time will produce an exception.

Parameters
statestate used only to determine which element of bodyForces to modify
bodythe body to apply the force to
torquethe torque to apply, specified in the inertial frame
bodyForcesthe set of system bodyForces to which this force is added

◆ assign()

void OpenSim::Force::assign ( Object aObject)
inlineoverride

This allows copy assignment in the Java GUI.

Exceptions
Exceptionif the argument is not of type Force.

◆ clone()

Force* OpenSim::Force::clone ( ) const
overridepure virtual

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.

Implemented in OpenSim::Millard2012AccelerationMuscle, OpenSim::Millard2012EquilibriumMuscle, OpenSim::HuntCrossleyForce, OpenSim::ElasticFoundationForce, OpenSim::ScalarActuator, OpenSim::HuntCrossleyForce, OpenSim::ElasticFoundationForce, OpenSim::Thelen2003Muscle, OpenSim::Muscle, OpenSim::ClutchedPathSpring, OpenSim::Delp1990Muscle_Deprecated, OpenSim::RigidTendonMuscle, OpenSim::CoordinateLimitForce, OpenSim::ExpressionBasedPointToPointForce, OpenSim::ExternalForce, OpenSim::ActivationFiberLengthMuscle, OpenSim::ExpressionBasedBushingForce, OpenSim::FunctionBasedBushingForce, OpenSim::PathSpring, OpenSim::PrescribedForce, OpenSim::TwoFrameLinker< Force, PhysicalFrame >, OpenSim::ActivationFiberLengthMuscle_Deprecated, OpenSim::BushingForce, OpenSim::Schutte1993Muscle_Deprecated, OpenSim::TorqueActuator, OpenSim::Ligament, OpenSim::BodyActuator, OpenSim::PointActuator, OpenSim::Thelen2003Muscle_Deprecated, OpenSim::PointToPointActuator, OpenSim::Actuator, OpenSim::CoordinateActuator, OpenSim::McKibbenActuator, OpenSim::SpringGeneralizedForce, OpenSim::PathActuator, OpenSim::PointToPointSpring, OpenSim::ElasticFoundationForce, OpenSim::HuntCrossleyForce, and OpenSim::ExpressionBasedCoordinateForce.

◆ computeForce()

virtual void OpenSim::Force::computeForce ( const SimTK::State &  state,
SimTK::Vector_< SimTK::SpatialVec > &  bodyForces,
SimTK::Vector &  generalizedForces 
) const
inlineprotectedvirtual

◆ computePotentialEnergy()

virtual double OpenSim::Force::computePotentialEnergy ( const SimTK::State &  state) const
protectedvirtual

Subclasses may optionally override this method to compute a contribution to the potential energy of the system.

The default implementation returns 0, which is appropriate for forces that do not contribute to potential energy.

Reimplemented in OpenSim::Muscle, OpenSim::BushingForce, and OpenSim::CoordinateLimitForce.

◆ extendAddToSystem()

void OpenSim::Force::extendAddToSystem ( SimTK::MultibodySystem &  system) const
overrideprotectedvirtual

Default is to create a ForceAdapter which is a SimTK::Force::Custom as the underlying computational component.

Subclasses override to employ other SimTK::Forces; be sure to invoke Force::extendAddToSystem() at the beginning of the overriding method.

Reimplemented from OpenSim::Component.

Reimplemented in OpenSim::Muscle, OpenSim::Ligament, and OpenSim::HuntCrossleyForce.

◆ extendInitStateFromProperties()

void OpenSim::Force::extendInitStateFromProperties ( SimTK::State &  state) const
overrideprotectedvirtual

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

Reimplemented from OpenSim::Component.

Reimplemented in OpenSim::Muscle.

◆ extendSetPropertiesFromState()

void OpenSim::Force::extendSetPropertiesFromState ( const SimTK::State &  state)
overrideprotectedvirtual

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

Reimplemented from OpenSim::Component.

Reimplemented in OpenSim::Muscle.

◆ get_appliesForce()

const bool& OpenSim::Force::get_appliesForce ( ) const
inline

Get the value of the appliesForce property.

◆ getClassName()

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

This returns "Force".

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::Force::getConcreteClassName ( ) const
overridepure virtual

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.

Implemented in OpenSim::Millard2012AccelerationMuscle, OpenSim::Millard2012EquilibriumMuscle, OpenSim::HuntCrossleyForce, OpenSim::ElasticFoundationForce, OpenSim::ScalarActuator, OpenSim::HuntCrossleyForce, OpenSim::ElasticFoundationForce, OpenSim::Thelen2003Muscle, OpenSim::Muscle, OpenSim::ClutchedPathSpring, OpenSim::Delp1990Muscle_Deprecated, OpenSim::RigidTendonMuscle, OpenSim::CoordinateLimitForce, OpenSim::ExpressionBasedPointToPointForce, OpenSim::ExternalForce, OpenSim::ActivationFiberLengthMuscle, OpenSim::ExpressionBasedBushingForce, OpenSim::FunctionBasedBushingForce, OpenSim::PathSpring, OpenSim::PrescribedForce, OpenSim::TwoFrameLinker< Force, PhysicalFrame >, OpenSim::ActivationFiberLengthMuscle_Deprecated, OpenSim::BushingForce, OpenSim::Schutte1993Muscle_Deprecated, OpenSim::TorqueActuator, OpenSim::Ligament, OpenSim::BodyActuator, OpenSim::PointActuator, OpenSim::Thelen2003Muscle_Deprecated, OpenSim::PointToPointActuator, OpenSim::Actuator, OpenSim::CoordinateActuator, OpenSim::McKibbenActuator, OpenSim::SpringGeneralizedForce, OpenSim::PathActuator, OpenSim::PointToPointSpring, OpenSim::ElasticFoundationForce, OpenSim::HuntCrossleyForce, and OpenSim::ExpressionBasedCoordinateForce.

◆ getRecordLabels()

◆ getRecordValues()

virtual OpenSim::Array<double> OpenSim::Force::getRecordValues ( const SimTK::State &  state) const
inlinevirtual

◆ hasGeometryPath()

virtual bool OpenSim::Force::hasGeometryPath ( ) const
inlinevirtual

Return a flag indicating whether the Force is applied along a Path.

If you override this method to return true for a specific subclass, it must also implement the getGeometryPath() method.

Reimplemented in OpenSim::Ligament, and OpenSim::PathActuator.

◆ safeDownCast()

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

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

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

◆ set_appliesForce()

void OpenSim::Force::set_appliesForce ( const bool &  value)
inline

Set the value of the appliesForce property.

◆ setAppliesForce()

void OpenSim::Force::setAppliesForce ( SimTK::State &  s,
bool  applyForce 
) const

Set whether or not the Force is applied.

◆ shouldBeParallelized()

virtual bool OpenSim::Force::shouldBeParallelized ( ) const
inlinevirtual

Tell SimBody to parallelize this force.

Should be set to true for any forces that will take time to complete their calcForce method. Note that all forces that set this flag to false will be put in series on a thread that is running in parallel with other forces that marked this flag as true.

◆ upd_appliesForce()

bool& OpenSim::Force::upd_appliesForce ( )
inline

Get a writable reference to the appliesForce property.

◆ updateFromXMLNode()

void OpenSim::Force::updateFromXMLNode ( SimTK::Xml::Element &  node,
int  versionNumber 
)
overrideprotectedvirtual

Handle a change in XML syntax for Sockets.

Reimplemented from OpenSim::Component.

Reimplemented in OpenSim::TwoFrameLinker< Force, PhysicalFrame >, OpenSim::PointToPointSpring, and OpenSim::PrescribedForce.

Friends And Related Function Documentation

◆ ForceAdapter

friend class ForceAdapter
friend

Member Data Documentation

◆ _index

SimTK::ResetOnCopy<SimTK::ForceIndex> OpenSim::Force::_index
protected

ID for the force in Simbody.

OpenSim Property, Socket, Output, Input Documentation

◆ appliesForce

bool OpenSim::Force::appliesForce

"Flag indicating whether the force is applied or not. If true the force" "is applied to the MultibodySystem otherwise the force is not applied." "NOTE: Prior to OpenSim 4.0, this behavior was controlled by the " "'isDisabled' property, where 'true' meant that force was not being " "applied. Thus, if 'isDisabled' is true, then 'appliesForce` is false."

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

See also
get_appliesForce(), upd_appliesForce(), set_appliesForce()

◆ potential_energy

double OpenSim::Force::potential_energy

Provides the value of computePotentialEnergy() and is available at stage SimTK::Stage::Velocity .

This output was generated with the OpenSim_DECLARE_OUTPUT macro.


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