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OpenSim::ExpressionBasedBushingForce Class Reference

A class implementing a bushing force driven by expressions relating forces to deviations. More...

#include <ExpressionBasedBushingForce.h>

Inheritance diagram for OpenSim::ExpressionBasedBushingForce:
OpenSim::Force OpenSim::ModelComponent OpenSim::Object

Public Member Functions

 ExpressionBasedBushingForce ()
 Default constructor leaves bodies unspecified, sets the bushing frames to be at their body origins, and sets all bushing parameters to zero.
 ExpressionBasedBushingForce (const std::string &body1Name, const SimTK::Vec3 &point1, const SimTK::Vec3 &orientation1, const std::string &body2Name, const SimTK::Vec3 &point2, const SimTK::Vec3 &orientation2)
 This convenience constructor defines and sets the bushing frames on each body, and sets all bushing functions to zero.
 ExpressionBasedBushingForce (const std::string &body1Name, const SimTK::Vec3 &point1, const SimTK::Vec3 &orientation1, const std::string &body2Name, const SimTK::Vec3 &point2, const SimTK::Vec3 &orientation2, const SimTK::Vec3 &transStiffness, const SimTK::Vec3 &rotStiffness, const SimTK::Vec3 &transDamping, const SimTK::Vec3 &rotDamping)
 This convenience constructor defines a bushing that behaves like a primitive bushing.
void setBody1ByName (const std::string &aBodyName)
 Set the name of the Body that will serve as body 1 for this bushing.
void setBody1BushingLocation (const SimTK::Vec3 &location, const SimTK::Vec3 &orientation=SimTK::Vec3(0))
 Set the location and orientation (optional) for bushing frame on body 1.
void setBody2ByName (const std::string &aBodyName)
 Set the name of the Body that will serve as body 2 for this bushing.
void setBody2BushingLocation (const SimTK::Vec3 &location, const SimTK::Vec3 &orientation=SimTK::Vec3(0))
 Set the location and orientation (optional) for bushing frame on body 2.
void setMomentVisualScale (double scale)
 Set the value used to scale the bushing moment on body2 when drawing it to screen.
void setForceVisualScale (double scale)
 Set the value used to scale the bushing force on body2 when drawing it to screen.
void setVisualAspectRatio (double ratio)
 Set the aspect ratio used to control the thickness of the bushing force and moment in drawn in the visualizer.
void setMxExpression (std::string expression)
 Set the expression defining Mx as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.
void setMyExpression (std::string expression)
 Set the expression defining My as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.
void setMzExpression (std::string expression)
 Set the expression defining Mz as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.
void setFxExpression (std::string expression)
 Set the expression defining Fx as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.
void setFyExpression (std::string expression)
 Set the expression defining Fy as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.
void setFzExpression (std::string expression)
 Set the expression defining Fz as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.
std::string getMxExpression ()
 Get the expression defining Mx as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.
std::string getMyExpression ()
 Get the expression defining My as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.
std::string getMzExpression ()
 Get the expression defining Mz as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.
std::string getFxExpression ()
 Get the expression defining Fx as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.
std::string getFyExpression ()
 Get the expression defining Fy as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.
std::string getFzExpression ()
 Get the expression defining Fz as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.
virtual SimTK::Vec6 computeDeflection (const SimTK::State &s) const
 Compute the deflection (spatial separation) of the two frames connected by the bushing force.
virtual void computeForce (const SimTK::State &s, SimTK::Vector_< SimTK::SpatialVec > &bodyForces, SimTK::Vector &generalizedForces) const
 Compute the bushing force contribution to the system and add in to appropriate bodyForce and/or system generalizedForce.
virtual OpenSim::Array
< std::string > 
getRecordLabels () const
 Potential energy calculation is not implemented.
virtual OpenSim::Array< double > getRecordValues (const SimTK::State &state) const
 Provide the value(s) to be reported that correspond to the labels.
Property declarations

These are the serializable properties associated with this class.

 OpenSim_DECLARE_OPTIONAL_PROPERTY (body_1, std::string,"One of the two bodies connected by the bushing.")
 OpenSim_DECLARE_OPTIONAL_PROPERTY (body_2, std::string,"The other of the two bodies connected by the bushing.")
 OpenSim_DECLARE_PROPERTY (location_body_1, SimTK::Vec3,"Location of bushing frame on body 1.")
 OpenSim_DECLARE_PROPERTY (orientation_body_1, SimTK::Vec3,"Orientation of bushing frame in body 1 as x-y-z, body fixed Euler rotations.")
 OpenSim_DECLARE_PROPERTY (location_body_2, SimTK::Vec3,"Location of bushing frame on body 2.")
 OpenSim_DECLARE_PROPERTY (orientation_body_2, SimTK::Vec3,"Orientation of bushing frame in body 2 as x-y-z, body fixed Euler rotations.")
 OpenSim_DECLARE_PROPERTY (Mx_expression, std::string,"Expression defining the contribution of theta_x deflection to the moment about body_2's x axis.""The expression is a string and can not have any whitespace separating characters.")
 OpenSim_DECLARE_PROPERTY (My_expression, std::string,"Expression defining the contribution of theta_y deflection to the moment about body_2's y axis.""The expression is a string and can not have any whitespace separating characters.")
 OpenSim_DECLARE_PROPERTY (Mz_expression, std::string,"Expression defining the contribution of theta_z deflection to the moment about body_2's z axis.""The expression is a string and can not have any whitespace separating characters.")
 OpenSim_DECLARE_PROPERTY (Fx_expression, std::string,"Expression defining the contribution of x deflection to the force in the x direction.""The expression is a string and can not have any whitespace separating characters.")
 OpenSim_DECLARE_PROPERTY (Fy_expression, std::string,"Expression defining the contribution of y deflection to the force in the y direction.""The expression is a string and can not have any whitespace separating characters.")
 OpenSim_DECLARE_PROPERTY (Fz_expression, std::string,"Expression defining the contribution of z deflection to the force in the z direction.""The expression is a string and can not have any whitespace separating characters.")
 OpenSim_DECLARE_OPTIONAL_PROPERTY (visual_aspect_ratio, double,"Scalar number signifying the ratio of length/diameter used to display the force and ""moment vectors.")
 OpenSim_DECLARE_OPTIONAL_PROPERTY (moment_visual_scale, double,"Value multiplying the bushing moments before displaying the moment vector")
 OpenSim_DECLARE_OPTIONAL_PROPERTY (force_visual_scale, double,"Value multiplying the bushing forces before displaying the force vector")
 OpenSim_DECLARE_PROPERTY (rotational_damping, SimTK::Vec3,"Damping parameters resisting relative angular velocity.")
 OpenSim_DECLARE_PROPERTY (translational_damping, SimTK::Vec3,"Damping parameters resisting relative translational velocity.")
- Public Member Functions inherited from OpenSim::Force
 Force (const Force &aForce)
 Implements a copy constructor just so it can invalidate the SimTK::Force index after copying.
Forceoperator= (const Force &aForce)
 Implements a copy assignment operator just so it can invalidate the SimTK::Force index after the assignment.
bool isDisabled (const SimTK::State &s) const
 Return if the Force is disabled or not.
void setDisabled (SimTK::State &s, bool disabled)
 Set the Force as disabled (true) or not (false).
virtual bool hasGeometryPath () const
 Return a flag indicating whether the Force is applied along a Path.
 OpenSim_DECLARE_PROPERTY (isDisabled, bool,"Flag indicating whether the force is disabled or not. Disabled means"" that the force is not active in subsequent dynamics realizations.")
 A Force element is active (enabled) by default.
- Public Member Functions inherited from OpenSim::ModelComponent
 ModelComponent ()
 Default constructor.
 ModelComponent (const std::string &aFileName, bool aUpdateFromXMLNode=true) SWIG_DECLARE_EXCEPTION
 Construct ModelComponent from an XML file.
 ModelComponent (SimTK::Xml::Element &aNode)
 Construct ModelComponent from a specific node in an XML document.
 ModelComponent (const ModelComponent &source)
 Construct ModelComponent with its contents copied from another ModelComponent; this is a deep copy so nothing is shared with the source after the copy.
virtual ~ModelComponent ()
 Destructor is virtual to allow concrete model component cleanup.
ModelComponentoperator= (const ModelComponent &aModelComponent)
 Assignment operator to copy contents of an existing component.
const ModelgetModel () const
 Get a const reference to the Model this component is part of.
ModelupdModel ()
 Get a modifiable reference to the Model this component is part of.
virtual void updateDisplayer (const SimTK::State &s) const
 In case the ModelComponent has a visual representation (VisualObject), override this method to update it.
virtual int getNumStateVariables () const
 Get the number of "Continuous" state variables maintained by the ModelComponent and its specified subcomponents.
virtual Array< std::string > getStateVariableNames () const
 Get the names of "continuous" state variables maintained by the ModelComponent and its subcomponents.
virtual SimTK::SystemYIndex getStateVariableSystemIndex (const std::string &stateVariableName) const
 Get the System Index of a state variable allocated by this ModelComponent.
int getModelingOption (const SimTK::State &state, const std::string &name) const
 Get a ModelingOption flag for this ModelComponent by name.
void setModelingOption (SimTK::State &state, const std::string &name, int flag) const
 Set the value of a ModelingOption flag for this ModelComponent.
double getStateVariable (const SimTK::State &state, const std::string &name) const
 Get the value of a state variable allocated by this ModelComponent.
void setStateVariable (SimTK::State &state, const std::string &name, double value) const
 Set the value of a state variable allocated by this ModelComponent by name.
double getDiscreteVariable (const SimTK::State &state, const std::string &name) const
 Get the value of a discrete variable allocated by this ModelComponent by name.
void setDiscreteVariable (SimTK::State &state, const std::string &name, double value) const
 Set the value of a discrete variable allocated by this ModelComponent by name.
template<typename T >
const T & getCacheVariable (const SimTK::State &state, const std::string &name) const
 Get the value of a cache variable allocated by this ModelComponent by name.
template<typename T >
T & updCacheVariable (const SimTK::State &state, const std::string &name) const
 Obtain a writable cache variable value allocated by this ModelComponent by name.
void markCacheVariableValid (const SimTK::State &state, const std::string &name) const
 After updating a cache variable value allocated by this ModelComponent, you can mark its value as valid, which will not change until the realization stage falls below the minimum set at the time the cache variable was created.
void markCacheVariableInvalid (const SimTK::State &state, const std::string &name) const
 Mark a cache variable value allocated by this ModelComponent as invalid.
bool isCacheVariableValid (const SimTK::State &state, const std::string &name) const
 Enables the to monitor the validity of the cache variable value using the returned flag.
template<typename T >
void setCacheVariable (const SimTK::State &state, const std::string &name, const T &value) const
 Set cache variable value allocated by this ModelComponent by name.
- Public Member Functions inherited from OpenSim::Object
virtual ~Object ()
 Virtual destructor for cleanup.
virtual Objectclone () const =0
 Create a new heap-allocated copy of the concrete object to which this Object refers.
virtual const std::string & getConcreteClassName () const =0
 Returns the class name of the concrete Object-derived class of the actual object referenced by this Object, as a string.
virtual const VisibleObjectgetDisplayer () const
 Methods to support making the object displayable in the GUI or Visualizer Implemented only in few objects.
virtual VisibleObjectupdDisplayer ()
 get Non const pointer to VisibleObject
bool isEqualTo (const Object &aObject) const
 Equality operator wrapper for use from languages not supporting operator overloading.
Objectoperator= (const Object &aObject)
 Copy assignment copies he base class fields, including the properties.
virtual bool operator== (const Object &aObject) const
 Determine if two objects are equal.
virtual bool operator< (const Object &aObject) const
 Provide an ordering for objects so they can be put in sorted containers.
void setName (const std::string &name)
 Set the name of the Object.
const std::string & getName () const
 Get the name of this Object.
void setDescription (const std::string &description)
 Set description, a one-liner summary.
const std::string & getDescription () const
 Get description, a one-liner summary.
const std::string & getAuthors () const
 Get Authors of this Object.
void setAuthors (const std::string &authors)
 Set Authors of this object, call this method in your constructor if needed.
const std::string & getReferences () const
 Get references or publications to cite if using this object.
void setReferences (const std::string &references)
 Set references or publications to cite if using this object.
int getNumProperties () const
 Determine how many properties are stored with this Object.
const AbstractPropertygetPropertyByIndex (int propertyIndex) const
 Get a const reference to a property by its index number, returned as an AbstractProperty.
AbstractPropertyupdPropertyByIndex (int propertyIndex)
 Get a writable reference to a property by its index number, returned as an AbstractProperty.
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.
const AbstractPropertygetPropertyByName (const std::string &name) const
 Get a const reference to a property by its name, returned as an AbstractProperty.
AbstractPropertyupdPropertyByName (const std::string &name)
 Get a writable reference to a property by its name, returned as an AbstractProperty.
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.
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.
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.
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.
bool isObjectUpToDateWithProperties () const
 Returns true if no property's value has changed since the last time setObjectIsUpToDateWithProperties() was called.
void readObjectFromXMLNodeOrFile (SimTK::Xml::Element &objectElement, int versionNumber)
 We're given an XML element from which we are to populate this Object.
virtual void updateFromXMLNode (SimTK::Xml::Element &objectElement, int versionNumber)
 Use this method to deserialize an object from a SimTK::Xml::Element.
virtual void updateXMLNode (SimTK::Xml::Element &parent)
 Serialize this object into the XML node that represents it.
bool getInlined () const
 Inlined means an in-memory Object that is not associated with an XMLDocument.
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.
std::string getDocumentFileName () const
 If there is a document associated with this object then return the file name maintained by the document.
void setAllPropertiesUseDefault (bool aUseDefault)
bool print (const std::string &fileName)
 Write this Object into an XML file of the given name; conventionally the suffix to use is ".osim".
std::string dump (bool dumpName=false)
 dump the XML representation of this Object into an std::string and return it.
void clearObjectIsUpToDateWithProperties ()
 For testing or debugging purposes, manually clear the "object is up to date with respect to properties" flag.
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.
const std::string & toString () const
 Wrapper to be used on Java side to display objects in tree; this returns just the object's name.
PropertySetgetPropertySet ()
 OBSOLETE: Get a reference to the PropertySet maintained by the Object.
const PropertySetgetPropertySet () const

Protected Member Functions

void generateDecorations (bool fixed, const ModelDisplayHints &hints, const SimTK::State &state, SimTK::Array_< SimTK::DecorativeGeometry > &geometryArray) const
 Optional method for generating arbitrary display geometry that reflects this ModelComponent at the specified state.
void ComputeForcesAtBushing (const SimTK::State &state, SimTK::SpatialVec &forces_on_M_in_ground, SimTK::SpatialVec &forces_on_F_in_ground) const
- Protected Member Functions inherited from OpenSim::Force
 Force ()
 Default constructor sets up Force-level properties; can only be called from a derived class constructor.
 Force (SimTK::Xml::Element &node)
 Deserialization from XML, necessary so that derived classes can (de)serialize.
virtual void initStateFromProperties (SimTK::State &state) const override
 Subclass should override; be sure to invoke Force::initStateFromProperties() at the beginning of the overriding method.
virtual void addToSystem (SimTK::MultibodySystem &system) const override
 Default is to create a ForceAdapter which is a SimTK::Force::Custom as the underlying computational component.
virtual void setPropertiesFromState (const SimTK::State &state) override
 Subclass should override; be sure to invoke Force::setPropertiesFromState() at the beginning of the overriding method.
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.
void applyForceToPoint (const SimTK::State &state, const OpenSim::Body &body, const SimTK::Vec3 &point, const SimTK::Vec3 &force, SimTK::Vector_< SimTK::SpatialVec > &bodyForces) const
 Apply a force at a particular point (a "station") on a given body.
void applyTorque (const SimTK::State &state, const OpenSim::Body &body, const SimTK::Vec3 &torque, SimTK::Vector_< SimTK::SpatialVec > &bodyForces) const
 Apply a torque to a particular body.
void applyGeneralizedForce (const SimTK::State &state, const Coordinate &coord, double force, SimTK::Vector &generalizedForces) const
 Apply a generalized force.
- Protected Member Functions inherited from OpenSim::ModelComponent
virtual void connectToModel (Model &model)
 Perform any necessary initializations required to connect the component into the Model, and check for error conditions.
virtual SimTK::Vector 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.
virtual void realizeTopology (SimTK::State &state) const
 Obtain state resources that are needed unconditionally, and perform computations that depend only on the system topology.
virtual void realizeModel (SimTK::State &state) const
 Obtain state resources that may be needed, depending on modeling options, and perform computations that depend only on topology and selected modeling options.
virtual void realizeInstance (const SimTK::State &state) const
 Perform computations that depend only on instance variables, like lengths and masses.
virtual void realizeTime (const SimTK::State &state) const
 Perform computations that depend only on time and earlier stages.
virtual void realizePosition (const SimTK::State &state) const
 Perform computations that depend only on position-level state variables and computations performed in earlier stages (including time).
virtual void realizeVelocity (const SimTK::State &state) const
 Perform computations that depend only on velocity-level state variables and computations performed in earlier stages (including position, and time).
virtual void realizeDynamics (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.
virtual void realizeAcceleration (const SimTK::State &state) const
 Perform computations that may depend on applied forces.
virtual void realizeReport (const SimTK::State &state) const
 Perform computations that may depend on anything but are only used for reporting and cannot affect subsequent simulation behavior.
void includeAsSubComponent (ModelComponent *aComponent)
 Include another ModelComponent as a Subcomponent of this ModelComponent.
void addModelingOption (const std::string &optionName, int maxFlagValue) const
 Add a modeling option (integer flag stored in the State) for use by this ModelComponent.
void addStateVariable (const std::string &stateVariableName, SimTK::Stage invalidatesStage=SimTK::Stage::Dynamics) const
 Add a continuous system state variable belonging to this ModelComponent, and assign a name by which to refer to it.
void addDiscreteVariable (const std::string &discreteVariableName, SimTK::Stage invalidatesStage) const
 Add a system discrete variable belonging to this ModelComponent, give it a name by which it can be referenced, and declare the lowest Stage that should be invalidated if this variable's value is changed.
template<class T >
void addCacheVariable (const std::string &cacheVariableName, const T &variablePrototype, SimTK::Stage dependsOnStage) const
 Add a state cache entry belonging to this ModelComponent to hold calculated values that must be automatically invalidated when certain state values change.
const int getStateIndex (const std::string &name) const
 Get the index of a ModelComponent's continuous state variable in the Subsystem for allocations.
const SimTK::DiscreteVariableIndex getDiscreteVariableIndex (const std::string &name) const
 Get the index of a ModelComponent's discrete variable in the Subsystem for allocations.
const SimTK::CacheEntryIndex getCacheVariableIndex (const std::string &name) const
 Get the index of a ModelComponent's cache variable in the Subsystem for allocations.
- Protected Member Functions inherited from OpenSim::Object
 Object ()
 The default constructor is only for use by constructors of derived types.
 Object (const std::string &fileName, bool aUpdateFromXMLNode=true) SWIG_DECLARE_EXCEPTION
 Constructor from a file, to be called from other constructors that take a file as input.
 Object (const Object &source)
 Copy constructor is invoked automatically by derived classes with default copy constructors; otherwise it must be invoked explicitly.
 Object (SimTK::Xml::Element &aElement)
 Construct the base class portion of an Object from a given Xml element that describes this Object.
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.
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.
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.
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.
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.
PropertyIndex getPropertyIndex (const std::string &name) const
 Look up a property by name and return its PropertyIndex if it is found.
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.
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.
void setDocument (XMLDocument *doc)
 Unconditionally set the XMLDocument associated with this object.
const XMLDocumentgetDocument () const
 Get a const pointer to the document (if any) associated with this object.
XMLDocumentupdDocument ()
 Get a writable pointer to the document (if any) associated with this object.

Protected Attributes

VisibleObject _displayer
 how to display the bushing
- Protected Attributes inherited from OpenSim::Force
SimTK::ForceIndex _index
 ID for the force in Simbody.
- Protected Attributes inherited from OpenSim::ModelComponent
Model_model
 The model this component belongs to.
- Protected Attributes inherited from OpenSim::Object
PropertySet _propertySet
 OBSOLETE: Property_Deprecated set for serializable member variables of this and derived classes.

Additional Inherited Members

- Static Public Member Functions inherited from OpenSim::Object
static void registerType (const Object &defaultObject)
 Register an instance of a class; if the class is already registered it will be replaced.
static void renameType (const std::string &oldTypeName, const std::string &newTypeName)
 Support versioning by associating the current Object type with an old name.
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.
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*.
static ObjectnewInstanceOfType (const std::string &concreteClassName)
 Create a new instance of the concrete Object type whose class name is given as concreteClassName.
static void getRegisteredTypenames (Array< std::string > &typeNames)
 Retrieve all the typenames registered so far.
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.
static void PrintPropertyInfo (std::ostream &os, const std::string &classNameDotPropertyName)
 Dump formatted property information to a given output stream, useful for creating a "help" facility for registered objects.
static void PrintPropertyInfo (std::ostream &os, const std::string &className, const std::string &propertyName)
 Same as the other signature but the class name and property name are provided as two separate strings.
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.
static const std::string & getClassName ()
 Return the name of this class as a string; i.e., "Object".
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.
static bool getSerializeAllDefaults ()
 Report the value of the "serialize all defaults" flag.
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.
static void setDebugLevel (int newLevel)
 Set the debug level to get verbose output.
static int getDebugLevel ()
 Get current setting of debug level.
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.
static void RegisterType (const Object &defaultObject)
 OBSOLETE alternate name for registerType().
static void RenameType (const std::string &oldName, const std::string &newName)
 OBSOLETE alternate name for renameType().
- Static Public Attributes inherited from OpenSim::Object
static const std::string DEFAULT_NAME
 Name used for default objects when they are serialized.

Detailed Description

A class implementing a bushing force driven by expressions relating forces to deviations.

These expressions are user defined expressions provided as strings that are parsed and evaluated during a simulation. Each expression can be a function of the bushing's rotational deflections (theta_x, theta_y, theta_z) and translational deflections, (delta_x, delta_y, delta_z). These user defined expressions can capture nonlinearities and coupling common in biologic structures.

A bushing force is the force increasing due to deviation between two frames. One can think of the Bushing as being composed of 3 translational and 3 torsional spring-dampers, which act along or about the bushing frames. Orientations are measured as x-y-z body-fixed Euler rotations. The underlying Force in Simbody is a SimtK::Force::LinearBushing.

Author
Matt DeMers

Constructor & Destructor Documentation

OpenSim::ExpressionBasedBushingForce::ExpressionBasedBushingForce ( )

Default constructor leaves bodies unspecified, sets the bushing frames to be at their body origins, and sets all bushing parameters to zero.

OpenSim::ExpressionBasedBushingForce::ExpressionBasedBushingForce ( const std::string &  body1Name,
const SimTK::Vec3 &  point1,
const SimTK::Vec3 &  orientation1,
const std::string &  body2Name,
const SimTK::Vec3 &  point2,
const SimTK::Vec3 &  orientation2 
)

This convenience constructor defines and sets the bushing frames on each body, and sets all bushing functions to zero.

OpenSim::ExpressionBasedBushingForce::ExpressionBasedBushingForce ( const std::string &  body1Name,
const SimTK::Vec3 &  point1,
const SimTK::Vec3 &  orientation1,
const std::string &  body2Name,
const SimTK::Vec3 &  point2,
const SimTK::Vec3 &  orientation2,
const SimTK::Vec3 &  transStiffness,
const SimTK::Vec3 &  rotStiffness,
const SimTK::Vec3 &  transDamping,
const SimTK::Vec3 &  rotDamping 
)

This convenience constructor defines a bushing that behaves like a primitive bushing.

Stiffnesses are used to define linear functions for force deflection profiles.

Member Function Documentation

virtual SimTK::Vec6 OpenSim::ExpressionBasedBushingForce::computeDeflection ( const SimTK::State &  s) const
virtual

Compute the deflection (spatial separation) of the two frames connected by the bushing force.

Angualar displacement expressed in Euler angles. The force and potential energy are determined by the deflection.

virtual void OpenSim::ExpressionBasedBushingForce::computeForce ( const SimTK::State &  s,
SimTK::Vector_< SimTK::SpatialVec > &  bodyForces,
SimTK::Vector &  generalizedForces 
) const
virtual

Compute the bushing force contribution to the system and add in to appropriate bodyForce and/or system generalizedForce.

Reimplemented from OpenSim::Force.

void OpenSim::ExpressionBasedBushingForce::ComputeForcesAtBushing ( const SimTK::State &  state,
SimTK::SpatialVec &  forces_on_M_in_ground,
SimTK::SpatialVec &  forces_on_F_in_ground 
) const
protected
void OpenSim::ExpressionBasedBushingForce::generateDecorations ( bool  fixed,
const ModelDisplayHints hints,
const SimTK::State &  state,
SimTK::Array_< SimTK::DecorativeGeometry > &  appendToThis 
) const
protectedvirtual

Optional method for generating arbitrary display geometry that reflects this ModelComponent at the specified state.

This will be called once to obtain ground- and body-fixed geometry (with fixed=true), and then once per frame (with fixed=false) to generate on-the-fly geometry such as rubber band lines, force arrows, labels, or debugging aids.

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

(bool fixed,
const ModelDisplayHints& hints,
const SimTK::State& state,
SimTK::Array_<SimTK::DecorativeGeometry>& appendToThis) const
{
// invoke parent class method
Super::generateDecorations(fixed,hints,state,appendToThis);
// ... your code goes here
}
Parameters
[in]fixedIf true, generate only geometry that is independent of time, configuration, and velocity. Otherwise generate only such dependent geometry.
[in]hintsSee documentation for ModelDisplayHints; you may want to alter the geometry you generate depending on what you find there. For example, you can determine whether the user wants to see debug geometry.
[in]stateThe State for which geometry should be produced. See below for more information.
[in,out]appendToThisArray to which generated geometry should be appended via the push_back() method.

When called with fixed=true only modeling options and parameters (Instance variables) should affect geometry; time, position, and velocity should not. In that case OpenSim will already have realized the state through Instance stage. When called with fixed=false, you may consult any relevant value in state. However, to avoid unnecessary computation, OpenSim guarantees only that state will have been realized through Position stage; if you need anything higher than that (reaction forces, for example) you should make sure the state is realized through Acceleration stage.

Reimplemented from OpenSim::ModelComponent.

std::string OpenSim::ExpressionBasedBushingForce::getFxExpression ( )
inline

Get the expression defining Fx as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.

std::string OpenSim::ExpressionBasedBushingForce::getFyExpression ( )
inline

Get the expression defining Fy as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.

std::string OpenSim::ExpressionBasedBushingForce::getFzExpression ( )
inline

Get the expression defining Fz as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.

std::string OpenSim::ExpressionBasedBushingForce::getMxExpression ( )
inline

Get the expression defining Mx as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.

std::string OpenSim::ExpressionBasedBushingForce::getMyExpression ( )
inline

Get the expression defining My as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.

std::string OpenSim::ExpressionBasedBushingForce::getMzExpression ( )
inline

Get the expression defining Mz as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.

virtual OpenSim::Array<std::string> OpenSim::ExpressionBasedBushingForce::getRecordLabels ( ) const
virtual

Potential energy calculation is not implemented.

Provide name(s) of the quantities (column labels) of the force value(s) to be reported.

Reimplemented from OpenSim::Force.

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

Provide the value(s) to be reported that correspond to the labels.

Reimplemented from OpenSim::Force.

OpenSim::ExpressionBasedBushingForce::OpenSim_DECLARE_OPTIONAL_PROPERTY ( body_1  ,
std::string  ,
"One of the two bodies connected by the bushing."   
)
OpenSim::ExpressionBasedBushingForce::OpenSim_DECLARE_OPTIONAL_PROPERTY ( body_2  ,
std::string  ,
"The other of the two bodies connected by the bushing."   
)
OpenSim::ExpressionBasedBushingForce::OpenSim_DECLARE_OPTIONAL_PROPERTY ( visual_aspect_ratio  ,
double  ,
"Scalar number signifying the ratio of length/diameter used to display the force and ""moment vectors."   
)
OpenSim::ExpressionBasedBushingForce::OpenSim_DECLARE_OPTIONAL_PROPERTY ( moment_visual_scale  ,
double  ,
"Value multiplying the bushing moments before displaying the moment vector"   
)
OpenSim::ExpressionBasedBushingForce::OpenSim_DECLARE_OPTIONAL_PROPERTY ( force_visual_scale  ,
double  ,
"Value multiplying the bushing forces before displaying the force vector"   
)
OpenSim::ExpressionBasedBushingForce::OpenSim_DECLARE_PROPERTY ( location_body_1  ,
SimTK::Vec3  ,
"Location of bushing frame on body 1."   
)
OpenSim::ExpressionBasedBushingForce::OpenSim_DECLARE_PROPERTY ( orientation_body_1  ,
SimTK::Vec3  ,
"Orientation of bushing frame in body 1 as x-y-  z,
body fixed Euler rotations."   
)
OpenSim::ExpressionBasedBushingForce::OpenSim_DECLARE_PROPERTY ( location_body_2  ,
SimTK::Vec3  ,
"Location of bushing frame on body 2."   
)
OpenSim::ExpressionBasedBushingForce::OpenSim_DECLARE_PROPERTY ( orientation_body_2  ,
SimTK::Vec3  ,
"Orientation of bushing frame in body 2 as x-y-  z,
body fixed Euler rotations."   
)
OpenSim::ExpressionBasedBushingForce::OpenSim_DECLARE_PROPERTY ( Mx_expression  ,
std::string  ,
"Expression defining the contribution of theta_x deflection to the moment about body_2's x axis.""The expression is a string and can not have any whitespace separating characters."   
)
OpenSim::ExpressionBasedBushingForce::OpenSim_DECLARE_PROPERTY ( My_expression  ,
std::string  ,
"Expression defining the contribution of theta_y deflection to the moment about body_2's y axis.""The expression is a string and can not have any whitespace separating characters."   
)
OpenSim::ExpressionBasedBushingForce::OpenSim_DECLARE_PROPERTY ( Mz_expression  ,
std::string  ,
"Expression defining the contribution of theta_z deflection to the moment about body_2's z axis.""The expression is a string and can not have any whitespace separating characters."   
)
OpenSim::ExpressionBasedBushingForce::OpenSim_DECLARE_PROPERTY ( Fx_expression  ,
std::string  ,
"Expression defining the contribution of x deflection to the force in the x direction.""The expression is a string and can not have any whitespace separating characters."   
)
OpenSim::ExpressionBasedBushingForce::OpenSim_DECLARE_PROPERTY ( Fy_expression  ,
std::string  ,
"Expression defining the contribution of y deflection to the force in the y direction.""The expression is a string and can not have any whitespace separating characters."   
)
OpenSim::ExpressionBasedBushingForce::OpenSim_DECLARE_PROPERTY ( Fz_expression  ,
std::string  ,
"Expression defining the contribution of z deflection to the force in the z direction.""The expression is a string and can not have any whitespace separating characters."   
)
OpenSim::ExpressionBasedBushingForce::OpenSim_DECLARE_PROPERTY ( rotational_damping  ,
SimTK::Vec3  ,
"Damping parameters resisting relative angular velocity."   
)
OpenSim::ExpressionBasedBushingForce::OpenSim_DECLARE_PROPERTY ( translational_damping  ,
SimTK::Vec3  ,
"Damping parameters resisting relative translational velocity."   
)
void OpenSim::ExpressionBasedBushingForce::setBody1BushingLocation ( const SimTK::Vec3 &  location,
const SimTK::Vec3 &  orientation = SimTK::Vec3(0) 
)

Set the location and orientation (optional) for bushing frame on body 1.

void OpenSim::ExpressionBasedBushingForce::setBody1ByName ( const std::string &  aBodyName)

Set the name of the Body that will serve as body 1 for this bushing.

void OpenSim::ExpressionBasedBushingForce::setBody2BushingLocation ( const SimTK::Vec3 &  location,
const SimTK::Vec3 &  orientation = SimTK::Vec3(0) 
)

Set the location and orientation (optional) for bushing frame on body 2.

void OpenSim::ExpressionBasedBushingForce::setBody2ByName ( const std::string &  aBodyName)

Set the name of the Body that will serve as body 2 for this bushing.

void OpenSim::ExpressionBasedBushingForce::setForceVisualScale ( double  scale)
inline

Set the value used to scale the bushing force on body2 when drawing it to screen.

A force of magnitude |F| will be drawn on screen with a length of (|F|*scale).

void OpenSim::ExpressionBasedBushingForce::setFxExpression ( std::string  expression)

Set the expression defining Fx as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.

void OpenSim::ExpressionBasedBushingForce::setFyExpression ( std::string  expression)

Set the expression defining Fy as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.

void OpenSim::ExpressionBasedBushingForce::setFzExpression ( std::string  expression)

Set the expression defining Fz as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.

void OpenSim::ExpressionBasedBushingForce::setMomentVisualScale ( double  scale)
inline

Set the value used to scale the bushing moment on body2 when drawing it to screen.

A moment of magnitude |M| will be drawn on screen with a length of (|M|*scale).

void OpenSim::ExpressionBasedBushingForce::setMxExpression ( std::string  expression)

Set the expression defining Mx as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.

void OpenSim::ExpressionBasedBushingForce::setMyExpression ( std::string  expression)

Set the expression defining My as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.

void OpenSim::ExpressionBasedBushingForce::setMzExpression ( std::string  expression)

Set the expression defining Mz as a function of the bushing deflections theta_x, theta_y, theta_z, delta_x, delta_y, delta_z.

void OpenSim::ExpressionBasedBushingForce::setVisualAspectRatio ( double  ratio)
inline

Set the aspect ratio used to control the thickness of the bushing force and moment in drawn in the visualizer.

ratio = length/diameter.

Member Data Documentation

VisibleObject OpenSim::ExpressionBasedBushingForce::_displayer
protected

how to display the bushing


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