API  4.1
For C++ developers
OpenSim::Millard2012EquilibriumMuscle Class Reference

This class implements a configurable equilibrium muscle model, as described in Millard et al. (2013). More...

+ Inheritance diagram for OpenSim::Millard2012EquilibriumMuscle:

OpenSim Properties, Sockets, Outputs, Inputs

Properties (single-value)
double fiber_damping
 "The linear damping of the fiber." More...
 
double default_activation
 "Assumed initial activation level if none is assigned." More...
 
double default_fiber_length
 "Assumed initial fiber length if none is assigned." More...
 
double activation_time_constant
 "Activation time constant (in seconds)." More...
 
double deactivation_time_constant
 "Deactivation time constant (in seconds)." More...
 
double minimum_activation
 "Activation lower bound." More...
 
double maximum_pennation_angle
 "Maximum pennation angle (in radians)." More...
 
Properties (unnamed)
ActiveForceLengthCurve ActiveForceLengthCurve
 "Active-force-length curve." More...
 
ForceVelocityCurve ForceVelocityCurve
 "Force-velocity curve." More...
 
FiberForceLengthCurve FiberForceLengthCurve
 "Passive-force-length curve." More...
 
TendonForceLengthCurve TendonForceLengthCurve
 "Tendon-force-length curve." More...
 
Outputs
double passive_fiber_elastic_force
 Provides the value of getPassiveFiberElasticForce() and is available at stage SimTK::Stage::Dynamics . More...
 
double passive_fiber_elastic_force_along_tendon
 Provides the value of getPassiveFiberElasticForceAlongTendon() and is available at stage SimTK::Stage::Dynamics . More...
 
double passive_fiber_damping_force
 Provides the value of getPassiveFiberDampingForce() and is available at stage SimTK::Stage::Dynamics . More...
 
double passive_fiber_damping_force_along_tendon
 Provides the value of getPassiveFiberDampingForceAlongTendon() and is available at stage SimTK::Stage::Dynamics . More...
 
- OpenSim Properties, Sockets, Outputs, Inputs inherited from OpenSim::Muscle
double max_isometric_force
 "Maximum isometric force that the fibers can generate" More...
 
double optimal_fiber_length
 "Optimal length of the muscle fibers" More...
 
double tendon_slack_length
 "Resting length of the tendon" More...
 
double pennation_angle_at_optimal
 "Angle between tendon and fibers at optimal fiber length expressed in radians" More...
 
double max_contraction_velocity
 "Maximum contraction velocity of the fibers, in optimal fiberlengths/second" More...
 
bool ignore_tendon_compliance
 "Compute muscle dynamics ignoring tendon compliance. Tendon is assumed to be rigid." More...
 
bool ignore_activation_dynamics
 "Compute muscle dynamics ignoring activation dynamics. Activation is equivalent to excitation." More...
 
double excitation
 Provides the value of getExcitation() and is available at stage SimTK::Stage::Dynamics . More...
 
double activation
 Provides the value of getActivation() and is available at stage SimTK::Stage::Dynamics . More...
 
double fiber_length
 Provides the value of getFiberLength() and is available at stage SimTK::Stage::Position . More...
 
double pennation_angle
 Provides the value of getPennationAngle() and is available at stage SimTK::Stage::Position . More...
 
double cos_pennation_angle
 Provides the value of getCosPennationAngle() and is available at stage SimTK::Stage::Position . More...
 
double tendon_length
 Provides the value of getTendonLength() and is available at stage SimTK::Stage::Position . More...
 
double normalized_fiber_length
 Provides the value of getNormalizedFiberLength() and is available at stage SimTK::Stage::Position . More...
 
double fiber_length_along_tendon
 Provides the value of getFiberLengthAlongTendon() and is available at stage SimTK::Stage::Position . More...
 
double tendon_strain
 Provides the value of getTendonStrain() and is available at stage SimTK::Stage::Position . More...
 
double passive_force_multiplier
 Provides the value of getPassiveForceMultiplier() and is available at stage SimTK::Stage::Position . More...
 
double active_force_length_multiplier
 Provides the value of getActiveForceLengthMultiplier() and is available at stage SimTK::Stage::Position . More...
 
double fiber_velocity
 Provides the value of getFiberVelocity() and is available at stage SimTK::Stage::Velocity . More...
 
double normalized_fiber_velocity
 Provides the value of getNormalizedFiberVelocity() and is available at stage SimTK::Stage::Velocity . More...
 
double fiber_velocity_along_tendon
 Provides the value of getFiberVelocityAlongTendon() and is available at stage SimTK::Stage::Velocity . More...
 
double tendon_velocity
 Provides the value of getTendonVelocity() and is available at stage SimTK::Stage::Velocity . More...
 
double force_velocity_multiplier
 Provides the value of getForceVelocityMultiplier() and is available at stage SimTK::Stage::Velocity . More...
 
double pennation_angular_velocity
 Provides the value of getPennationAngularVelocity() and is available at stage SimTK::Stage::Velocity . More...
 
double fiber_force
 Provides the value of getFiberForce() and is available at stage SimTK::Stage::Dynamics . More...
 
double fiber_force_along_tendon
 Provides the value of getFiberForceAlongTendon() and is available at stage SimTK::Stage::Dynamics . More...
 
double active_fiber_force
 Provides the value of getActiveFiberForce() and is available at stage SimTK::Stage::Dynamics . More...
 
double passive_fiber_force
 Provides the value of getPassiveFiberForce() and is available at stage SimTK::Stage::Dynamics . More...
 
double active_fiber_force_along_tendon
 Provides the value of getActiveFiberForceAlongTendon() and is available at stage SimTK::Stage::Dynamics . More...
 
double passive_fiber_force_along_tendon
 Provides the value of getPassiveFiberForceAlongTendon() and is available at stage SimTK::Stage::Dynamics . More...
 
double tendon_force
 Provides the value of getTendonForce() and is available at stage SimTK::Stage::Dynamics . More...
 
double fiber_stiffness
 Provides the value of getFiberStiffness() and is available at stage SimTK::Stage::Dynamics . More...
 
double fiber_stiffness_along_tendon
 Provides the value of getFiberStiffnessAlongTendon() and is available at stage SimTK::Stage::Dynamics . More...
 
double tendon_stiffness
 Provides the value of getTendonStiffness() and is available at stage SimTK::Stage::Dynamics . More...
 
double muscle_stiffness
 Provides the value of getMuscleStiffness() and is available at stage SimTK::Stage::Dynamics . More...
 
double fiber_active_power
 Provides the value of getFiberActivePower() and is available at stage SimTK::Stage::Dynamics . More...
 
double fiber_passive_power
 Provides the value of getFiberPassivePower() and is available at stage SimTK::Stage::Dynamics . More...
 
double tendon_power
 Provides the value of getTendonPower() and is available at stage SimTK::Stage::Dynamics . More...
 
double muscle_power
 Provides the value of getMusclePower() and is available at stage SimTK::Stage::Dynamics . More...
 
- OpenSim Properties, Sockets, Outputs, Inputs inherited from OpenSim::PathActuator
GeometryPath GeometryPath
 "The set of points defining the path of the actuator." More...
 
double optimal_force
 "The maximum force this actuator can produce." More...
 
double tension
 Provides the value of computeActuation() and is available at stage SimTK::Stage::Acceleration . More...
 
- OpenSim Properties, Sockets, Outputs, Inputs inherited from OpenSim::ScalarActuator
double min_control
 "Minimum allowed value for control signal. Used primarily when solving " "for control values." More...
 
double max_control
 "Maximum allowed value for control signal. Used primarily when solving " "for control values." More...
 
double actuation
 Provides the value of getActuation() and is available at stage SimTK::Stage::Velocity . More...
 
double speed
 Provides the value of getSpeed() and is available at stage SimTK::Stage::Velocity . More...
 
- OpenSim Properties, Sockets, Outputs, Inputs inherited from OpenSim::Actuator
double power
 Provides the value of getPower() and is available at stage SimTK::Stage::Dynamics . More...
 
- OpenSim Properties, Sockets, Outputs, Inputs inherited from OpenSim::Force
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...
 
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

 Millard2012EquilibriumMuscle ()
 Default constructor. More...
 
 Millard2012EquilibriumMuscle (const std::string &aName, double aMaxIsometricForce, double aOptimalFiberLength, double aTendonSlackLength, double aPennationAngle)
 Constructs a functional muscle using default curves and activation model parameters. More...
 
bool getUseFiberDamping () const
 
double getFiberDamping () const
 
double getDefaultActivation () const
 
double getDefaultFiberLength () const
 
double getActivationTimeConstant () const
 
double getDeactivationTimeConstant () const
 
double getMinimumActivation () const
 
const ActiveForceLengthCurvegetActiveForceLengthCurve () const
 
const ForceVelocityCurvegetForceVelocityCurve () const
 
const FiberForceLengthCurvegetFiberForceLengthCurve () const
 
const TendonForceLengthCurvegetTendonForceLengthCurve () const
 
const MuscleFixedWidthPennationModelgetPennationModel () const
 
const MuscleFirstOrderActivationDynamicModelgetActivationModel () const
 
double getMinimumFiberLength () const
 
double getMinimumFiberLengthAlongTendon () const
 
double getTendonForceMultiplier (SimTK::State &s) const
 
double getFiberStiffnessAlongTendon (const SimTK::State &s) const
 
double getFiberVelocity (const SimTK::State &s) const
 
double getActivationDerivative (const SimTK::State &s) const
 
double getPassiveFiberElasticForce (const SimTK::State &s) const
 get the portion of the passive fiber force generated by the elastic element only (N) More...
 
double getPassiveFiberElasticForceAlongTendon (const SimTK::State &s) const
 get the portion of the passive fiber force generated by the elastic element only, projected onto the tendon direction (N) More...
 
double getPassiveFiberDampingForce (const SimTK::State &s) const
 get the portion of the passive fiber force generated by the damping element only (N) More...
 
double getPassiveFiberDampingForceAlongTendon (const SimTK::State &s) const
 get the portion of the passive fiber force generated by the damping element only, projected onto the tendon direction (N) More...
 
void setMuscleConfiguration (bool ignoreTendonCompliance, bool ignoreActivationDynamics, double dampingCoefficient)
 
void setFiberDamping (double dampingCoefficient)
 
void setDefaultActivation (double activation)
 
void setActivation (SimTK::State &s, double activation) const override
 
void setDefaultFiberLength (double fiberLength)
 
void setActivationTimeConstant (double activationTimeConstant)
 
void setDeactivationTimeConstant (double deactivationTimeConstant)
 
void setMinimumActivation (double minimumActivation)
 
void setActiveForceLengthCurve (ActiveForceLengthCurve &aActiveForceLengthCurve)
 
void setForceVelocityCurve (ForceVelocityCurve &aForceVelocityCurve)
 
void setFiberForceLengthCurve (FiberForceLengthCurve &aFiberForceLengthCurve)
 
void setTendonForceLengthCurve (TendonForceLengthCurve &aTendonForceLengthCurve)
 
void setFiberLength (SimTK::State &s, double fiberLength) const
 
double computeActuation (const SimTK::State &s) const override final
 
void computeInitialFiberEquilibrium (SimTK::State &s) const override
 Computes the fiber length such that the fiber and tendon are developing the same force, distributing the velocity of the entire musculotendon actuator between the fiber and tendon according to their relative stiffnesses. More...
 
void computeFiberEquilibrium (SimTK::State &s, bool solveForVelocity=false) const
 Computes the fiber length such that the fiber and tendon are developing the same force, either assuming muscle-tendon velocity as provided by the state or zero as designated by the useZeroVelocity flag. More...
 
void extendPostScale (const SimTK::State &s, const ScaleSet &scaleSet) override
 Adjust the properties of the muscle after the model has been scaled. More...
 
Property-related functions
const double & get_fiber_damping () const
 Get the value of the fiber_damping property. More...
 
double & upd_fiber_damping ()
 Get a writable reference to the fiber_damping property. More...
 
void set_fiber_damping (const double &value)
 Set the value of the fiber_damping property. More...
 
const double & get_default_activation () const
 Get the value of the default_activation property. More...
 
double & upd_default_activation ()
 Get a writable reference to the default_activation property. More...
 
void set_default_activation (const double &value)
 Set the value of the default_activation property. More...
 
const double & get_default_fiber_length () const
 Get the value of the default_fiber_length property. More...
 
double & upd_default_fiber_length ()
 Get a writable reference to the default_fiber_length property. More...
 
void set_default_fiber_length (const double &value)
 Set the value of the default_fiber_length property. More...
 
const double & get_activation_time_constant () const
 Get the value of the activation_time_constant property. More...
 
double & upd_activation_time_constant ()
 Get a writable reference to the activation_time_constant property. More...
 
void set_activation_time_constant (const double &value)
 Set the value of the activation_time_constant property. More...
 
const double & get_deactivation_time_constant () const
 Get the value of the deactivation_time_constant property. More...
 
double & upd_deactivation_time_constant ()
 Get a writable reference to the deactivation_time_constant property. More...
 
void set_deactivation_time_constant (const double &value)
 Set the value of the deactivation_time_constant property. More...
 
const double & get_minimum_activation () const
 Get the value of the minimum_activation property. More...
 
double & upd_minimum_activation ()
 Get a writable reference to the minimum_activation property. More...
 
void set_minimum_activation (const double &value)
 Set the value of the minimum_activation property. More...
 
const double & get_maximum_pennation_angle () const
 Get the value of the maximum_pennation_angle property. More...
 
double & upd_maximum_pennation_angle ()
 Get a writable reference to the maximum_pennation_angle property. More...
 
void set_maximum_pennation_angle (const double &value)
 Set the value of the maximum_pennation_angle property. More...
 
const ActiveForceLengthCurveget_ActiveForceLengthCurve () const
 Get the value of the ActiveForceLengthCurve property. More...
 
ActiveForceLengthCurveupd_ActiveForceLengthCurve ()
 Get a writable reference to the ActiveForceLengthCurve property. More...
 
void set_ActiveForceLengthCurve (const ActiveForceLengthCurve &value)
 Set the value of the ActiveForceLengthCurve property. More...
 
const ForceVelocityCurveget_ForceVelocityCurve () const
 Get the value of the ForceVelocityCurve property. More...
 
ForceVelocityCurveupd_ForceVelocityCurve ()
 Get a writable reference to the ForceVelocityCurve property. More...
 
void set_ForceVelocityCurve (const ForceVelocityCurve &value)
 Set the value of the ForceVelocityCurve property. More...
 
const FiberForceLengthCurveget_FiberForceLengthCurve () const
 Get the value of the FiberForceLengthCurve property. More...
 
FiberForceLengthCurveupd_FiberForceLengthCurve ()
 Get a writable reference to the FiberForceLengthCurve property. More...
 
void set_FiberForceLengthCurve (const FiberForceLengthCurve &value)
 Set the value of the FiberForceLengthCurve property. More...
 
const TendonForceLengthCurveget_TendonForceLengthCurve () const
 Get the value of the TendonForceLengthCurve property. More...
 
TendonForceLengthCurveupd_TendonForceLengthCurve ()
 Get a writable reference to the TendonForceLengthCurve property. More...
 
void set_TendonForceLengthCurve (const TendonForceLengthCurve &value)
 Set the value of the TendonForceLengthCurve property. More...
 
- Public Member Functions inherited from OpenSim::Muscle
const double & get_max_isometric_force () const
 Get the value of the max_isometric_force property. More...
 
double & upd_max_isometric_force ()
 Get a writable reference to the max_isometric_force property. More...
 
void set_max_isometric_force (const double &value)
 Set the value of the max_isometric_force property. More...
 
const double & get_optimal_fiber_length () const
 Get the value of the optimal_fiber_length property. More...
 
double & upd_optimal_fiber_length ()
 Get a writable reference to the optimal_fiber_length property. More...
 
void set_optimal_fiber_length (const double &value)
 Set the value of the optimal_fiber_length property. More...
 
const double & get_tendon_slack_length () const
 Get the value of the tendon_slack_length property. More...
 
double & upd_tendon_slack_length ()
 Get a writable reference to the tendon_slack_length property. More...
 
void set_tendon_slack_length (const double &value)
 Set the value of the tendon_slack_length property. More...
 
const double & get_pennation_angle_at_optimal () const
 Get the value of the pennation_angle_at_optimal property. More...
 
double & upd_pennation_angle_at_optimal ()
 Get a writable reference to the pennation_angle_at_optimal property. More...
 
void set_pennation_angle_at_optimal (const double &value)
 Set the value of the pennation_angle_at_optimal property. More...
 
const double & get_max_contraction_velocity () const
 Get the value of the max_contraction_velocity property. More...
 
double & upd_max_contraction_velocity ()
 Get a writable reference to the max_contraction_velocity property. More...
 
void set_max_contraction_velocity (const double &value)
 Set the value of the max_contraction_velocity property. More...
 
const bool & get_ignore_tendon_compliance () const
 Get the value of the ignore_tendon_compliance property. More...
 
bool & upd_ignore_tendon_compliance ()
 Get a writable reference to the ignore_tendon_compliance property. More...
 
void set_ignore_tendon_compliance (const bool &value)
 Set the value of the ignore_tendon_compliance property. More...
 
const bool & get_ignore_activation_dynamics () const
 Get the value of the ignore_activation_dynamics property. More...
 
bool & upd_ignore_activation_dynamics ()
 Get a writable reference to the ignore_activation_dynamics property. More...
 
void set_ignore_activation_dynamics (const bool &value)
 Set the value of the ignore_activation_dynamics property. More...
 
 Muscle ()
 Default constructor. More...
 
double getMaxIsometricForce () const
 get/set the maximum isometric force (in N) that the fibers can generate More...
 
void setMaxIsometricForce (double maxIsometricForce)
 
double getOptimalFiberLength () const
 get/set the optimal length (in m) of the muscle fibers (lumped as a single fiber) More...
 
void setOptimalFiberLength (double optimalFiberLength)
 
double getTendonSlackLength () const
 get/set the resting (slack) length (in m) of the tendon that is in series with the muscle fiber More...
 
void setTendonSlackLength (double tendonSlackLength)
 
double getPennationAngleAtOptimalFiberLength () const
 get/set the angle (in radians) between fibers at their optimal fiber length and the tendon More...
 
void setPennationAngleAtOptimalFiberLength (double pennationAngle)
 
double getMaxContractionVelocity () const
 get/set the maximum contraction velocity of the fibers, in optimal fiber-lengths per second More...
 
void setMaxContractionVelocity (double maxContractionVelocity)
 
bool getIgnoreTendonCompliance (const SimTK::State &s) const
 Get/set Modeling (runtime) option to ignore tendon compliance when computing muscle dynamics. More...
 
void setIgnoreTendonCompliance (SimTK::State &s, bool ignore) const
 
bool getIgnoreActivationDynamics (const SimTK::State &s) const
 Get/set Modeling (runtime) option to ignore activation dynamics when computing muscle dynamics. More...
 
void setIgnoreActivationDynamics (SimTK::State &s, bool ignore) const
 
virtual double getActivation (const SimTK::State &s) const
 get the activation level of the muscle, which modulates the active force of the muscle and has a normalized (0 to 1) value Note: method remains virtual to permit override by deprecated muscles. More...
 
double getFiberLength (const SimTK::State &s) const
 get the current working fiber length (m) for the muscle More...
 
double getPennationAngle (const SimTK::State &s) const
 get the current pennation angle (radians) between the fiber and tendon at the current fiber length More...
 
double getCosPennationAngle (const SimTK::State &s) const
 get the cosine of the current pennation angle (radians) between the fiber and tendon at the current fiber length More...
 
double getTendonLength (const SimTK::State &s) const
 get the current tendon length (m) given the current joint angles and fiber length More...
 
double getNormalizedFiberLength (const SimTK::State &s) const
 get the current normalized fiber length (fiber_length/optimal_fiber_length) More...
 
double getFiberLengthAlongTendon (const SimTK::State &s) const
 get the current fiber length (m) projected (*cos(pennationAngle)) onto the tendon direction More...
 
double getTendonStrain (const SimTK::State &s) const
 get the current tendon strain (delta_l/tendon_slack_length is dimensionless) More...
 
double getFiberPotentialEnergy (const SimTK::State &s) const
 the potential energy (J) stored in the fiber due to its parallel elastic element More...
 
double getTendonPotentialEnergy (const SimTK::State &s) const
 the potential energy (J) stored in the tendon More...
 
double getMusclePotentialEnergy (const SimTK::State &s) const
 the total potential energy (J) stored in the muscle More...
 
double getPassiveForceMultiplier (const SimTK::State &s) const
 get the passive fiber (parallel elastic element) force multiplier More...
 
double getActiveForceLengthMultiplier (const SimTK::State &s) const
 get the active fiber (contractile element) force multiplier due to current fiber length More...
 
double getFiberVelocity (const SimTK::State &s) const
 get current fiber velocity (m/s) positive is lengthening More...
 
double getNormalizedFiberVelocity (const SimTK::State &s) const
 get normalized fiber velocity. More...
 
double getFiberVelocityAlongTendon (const SimTK::State &s) const
 get the current fiber velocity (m/s) projected onto the tendon direction More...
 
double getPennationAngularVelocity (const SimTK::State &s) const
 get pennation angular velocity (radians/s) More...
 
double getTendonVelocity (const SimTK::State &s) const
 get the tendon velocity (m/s) positive is lengthening More...
 
double getForceVelocityMultiplier (const SimTK::State &s) const
 get the dimensionless multiplier resulting from the fiber's force-velocity curve More...
 
double getFiberForce (const SimTK::State &s) const
 get the current fiber force (N) applied to the tendon More...
 
double getFiberForceAlongTendon (const SimTK::State &s) const
 get the force of the fiber (N/m) along the direction of the tendon More...
 
double getActiveFiberForce (const SimTK::State &s) const
 get the current active fiber force (N) due to activation*force_length*force_velocity relationships More...
 
double getPassiveFiberForce (const SimTK::State &s) const
 get the total force applied by all passive elements in the fiber (N) More...
 
double getActiveFiberForceAlongTendon (const SimTK::State &s) const
 get the current active fiber force (N) projected onto the tendon direction More...
 
double getPassiveFiberForceAlongTendon (const SimTK::State &s) const
 get the total force applied by all passive elements in the fiber (N) projected onto the tendon direction More...
 
double getTendonForce (const SimTK::State &s) const
 get the current tendon force (N) applied to bones More...
 
double getFiberStiffness (const SimTK::State &s) const
 get the current fiber stiffness (N/m) defined as the partial derivative of fiber force with respect to fiber length More...
 
double getFiberStiffnessAlongTendon (const SimTK::State &s) const
 get the stiffness of the fiber (N/m) along the direction of the tendon, that is the partial derivative of the fiber force along the tendon with respect to small changes in fiber length along the tendon More...
 
double getTendonStiffness (const SimTK::State &s) const
 get the current tendon stiffness (N/m) defined as the partial derivative of tendon force with respect to tendon length More...
 
double getMuscleStiffness (const SimTK::State &s) const
 get the current muscle stiffness (N/m) defined as the partial derivative of muscle force with respect to muscle length More...
 
double getFiberActivePower (const SimTK::State &s) const
 get the current active fiber power (W) More...
 
double getFiberPassivePower (const SimTK::State &s) const
 get the current passive fiber power (W) More...
 
double getTendonPower (const SimTK::State &s) const
 get the current tendon power (W) More...
 
double getMusclePower (const SimTK::State &s) const
 get the current muscle power (W) More...
 
double getStress (const SimTK::State &s) const override
 get the stress in the muscle (part of the Actuator interface as well) More...
 
void setExcitation (SimTK::State &s, double excitation) const
 set the excitation (control) for this muscle. More...
 
double getExcitation (const SimTK::State &s) const
 
void computeEquilibrium (SimTK::State &s) const override final
 Find and set the equilibrium state of the muscle (if any) More...
 
void assign (Object &aObject) override
 This allows copy assignment in the Java GUI. More...
 
- Public Member Functions inherited from OpenSim::PathActuator
 PathActuator ()
 
GeometryPathupdGeometryPath ()
 
const GeometryPathgetGeometryPath () const
 
bool hasGeometryPath () const override
 Return a flag indicating whether the Force is applied along a Path. More...
 
void setOptimalForce (double aOptimalForce)
 
double getOptimalForce () const override
 
virtual double getLength (const SimTK::State &s) const
 
virtual double getLengtheningSpeed (const SimTK::State &s) const
 
double getPower (const SimTK::State &s) const override
 
double getStress (const SimTK::State &s) const override
 
void addNewPathPoint (const std::string &proposedName, const PhysicalFrame &aBody, const SimTK::Vec3 &aPositionOnBody)
 Note that this function does not maintain the State and so should be used only before a valid State is created. More...
 
double computeActuation (const SimTK::State &s) const override
 
virtual double computeMomentArm (const SimTK::State &s, Coordinate &aCoord) const
 
const GeometryPathget_GeometryPath () const
 Get the value of the GeometryPath property. More...
 
GeometryPathupd_GeometryPath ()
 Get a writable reference to the GeometryPath property. More...
 
void set_GeometryPath (const GeometryPath &value)
 Set the value of the GeometryPath property. More...
 
const double & get_optimal_force () const
 Get the value of the optimal_force property. More...
 
double & upd_optimal_force ()
 Get a writable reference to the optimal_force property. More...
 
void set_optimal_force (const double &value)
 Set the value of the optimal_force property. More...
 
void assign (Object &aObject) override
 This allows copy assignment in the Java GUI. More...
 
PathActuatorclone () const override
 Create a new heap-allocated copy of the concrete object to which this Object refers. More...
 
const std::string & getConcreteClassName () const override
 Returns the class name of the concrete Object-derived class of the actual object referenced by this Object, as a string. More...
 
- Public Member Functions inherited from OpenSim::ScalarActuator
 ScalarActuator ()
 
virtual double getControl (const SimTK::State &s) const
 Convenience method to get control given scalar (double) valued control. More...
 
int numControls () const override
 
virtual void setActuation (const SimTK::State &s, double aActuation) const
 
virtual double getActuation (const SimTK::State &s) const
 
virtual void setSpeed (const SimTK::State &s, double aspeed) const
 
virtual double getSpeed (const SimTK::State &s) const
 
void setMinControl (const double &aMinControl)
 Methods to manage the bounds on ScalarActuator's control. More...
 
double getMinControl () const
 
void setMaxControl (const double &aMaxControl)
 
double getMaxControl () const
 
void overrideActuation (SimTK::State &s, bool flag) const
 Enable/disable a ScalarActuator's override actuation. More...
 
bool isActuationOverridden (const SimTK::State &s) const
 return ScalarActuator's override status More...
 
void setOverrideActuation (SimTK::State &s, double value) const
 set the actuation value used when the override is true More...
 
double getOverrideActuation (const SimTK::State &s) const
 return override actuation More...
 
const double & get_min_control () const
 Get the value of the min_control property. More...
 
double & upd_min_control ()
 Get a writable reference to the min_control property. More...
 
void set_min_control (const double &value)
 Set the value of the min_control property. More...
 
const double & get_max_control () const
 Get the value of the max_control property. More...
 
double & upd_max_control ()
 Get a writable reference to the max_control property. More...
 
void set_max_control (const double &value)
 Set the value of the max_control property. More...
 
void assign (Object &aObject) override
 This allows copy assignment in the Java GUI. More...
 
- Public Member Functions inherited from OpenSim::Actuator
 Actuator ()
 
virtual const SimTK::Vector getDefaultControls ()
 Actuator default controls are zero. More...
 
virtual const SimTK::VectorView_< double > getControls (const SimTK::State &s) const
 
virtual void getControls (const SimTK::Vector &modelControls, SimTK::Vector &actuatorControls) const
 Convenience methods for getting, setting and adding to actuator controls from/into the model controls. More...
 
virtual void setControls (const SimTK::Vector &actuatorControls, SimTK::Vector &modelControls) const
 set actuator controls subvector into the right slot in the system-wide model controls More...
 
virtual void addInControls (const SimTK::Vector &actuatorControls, SimTK::Vector &modelControls) const
 add actuator controls to the values already occupying the slot in the system-wide model controls More...
 
void assign (Object &aObject) override
 This allows copy assignment in the Java GUI. More...
 
- Public Member Functions inherited from OpenSim::Force
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...
 
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...
 
void assign (Object &aObject) override
 This allows copy assignment in the Java GUI. More...
 
- Public Member Functions inherited from OpenSim::ModelComponent
 ModelComponent ()
 Default constructor. More...
 
 ModelComponent (const std::string &aFileName, bool aUpdateFromXMLNode=true)
 Construct ModelComponent from an XML file. More...
 
 ModelComponent (SimTK::Xml::Element &aNode)
 Construct ModelComponent from a specific node in an XML document. More...
 
virtual ~ModelComponent ()
 Destructor is virtual to allow concrete model component cleanup. More...
 
void connectToModel (Model &model)
 Connect this ModelComponent to its aggregate- a Model. More...
 
const 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 Millard2012EquilibriumMuscle Self
 This typedef might be useful within the member functions of this class. More...
 
typedef Muscle Super
 Use this typedef to refer to the superclass of this class. More...
 
- Public Types inherited from OpenSim::Muscle
typedef Muscle Self
 This typedef might be useful within the member functions of this class. More...
 
typedef PathActuator Super
 Use this typedef to refer to the superclass of this class. More...
 
- Public Types inherited from OpenSim::PathActuator
typedef PathActuator Self
 This typedef might be useful within the member functions of this class. More...
 
typedef ScalarActuator Super
 Use this typedef to refer to the superclass of this class. More...
 
- Public Types inherited from OpenSim::ScalarActuator
typedef ScalarActuator Self
 This typedef might be useful within the member functions of this class. More...
 
typedef Actuator Super
 Use this typedef to refer to the superclass of this class. More...
 
- Public Types inherited from OpenSim::Actuator
typedef Actuator Self
 This typedef might be useful within the member functions of this class. More...
 
typedef Force Super
 Use this typedef to refer to the superclass of this class. More...
 
- Public Types inherited from OpenSim::Force
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

double getStateVariableDeriv (const SimTK::State &s, const std::string &aStateName) const
 Gets the derivative of an actuator state by index. More...
 
void setStateVariableDeriv (const SimTK::State &s, const std::string &aStateName, double aValue) const
 Sets the derivative of an actuator state specified by name. More...
 
void calcMuscleLengthInfo (const SimTK::State &s, MuscleLengthInfo &mli) const override
 Calculate the position-related values associated with the muscle state (fiber and tendon lengths, normalized lengths, pennation angle, etc.). More...
 
void calcFiberVelocityInfo (const SimTK::State &s, FiberVelocityInfo &fvi) const override
 Calculate the velocity-related values associated with the muscle state (fiber and tendon velocities, normalized velocities, pennation angular velocity, etc.). More...
 
void calcMuscleDynamicsInfo (const SimTK::State &s, MuscleDynamicsInfo &mdi) const override
 Calculate the dynamics-related values associated with the muscle state (from the active- and passive-force-length curves, the force-velocity curve, and the tendon-force-length curve). More...
 
void calcMusclePotentialEnergyInfo (const SimTK::State &s, MusclePotentialEnergyInfo &mpei) const override
 Calculate the potential energy values associated with the muscle. More...
 
void extendConnectToModel (Model &model) override
 Sets up the ModelComponent from the model, if necessary. More...
 
void extendAddToSystem (SimTK::MultibodySystem &system) const override
 Creates the ModelComponent so that it can be used in simulation. More...
 
void extendInitStateFromProperties (SimTK::State &s) const override
 Initializes the state of the ModelComponent. More...
 
void extendSetPropertiesFromState (const SimTK::State &s) override
 Sets the default state for the ModelComponent. More...
 
void computeStateVariableDerivatives (const SimTK::State &s) const override
 Computes state variable derivatives. More...
 
- Protected Member Functions inherited from OpenSim::Muscle
const MuscleLengthInfogetMuscleLengthInfo (const SimTK::State &s) const
 Developer Access to intermediate values calculate by the muscle model. More...
 
MuscleLengthInfoupdMuscleLengthInfo (const SimTK::State &s) const
 
const FiberVelocityInfogetFiberVelocityInfo (const SimTK::State &s) const
 
FiberVelocityInfoupdFiberVelocityInfo (const SimTK::State &s) const
 
const MuscleDynamicsInfogetMuscleDynamicsInfo (const SimTK::State &s) const
 
MuscleDynamicsInfoupdMuscleDynamicsInfo (const SimTK::State &s) const
 
const MusclePotentialEnergyInfogetMusclePotentialEnergyInfo (const SimTK::State &s) const
 
MusclePotentialEnergyInfoupdMusclePotentialEnergyInfo (const SimTK::State &s) const
 
void computeForce (const SimTK::State &state, SimTK::Vector_< SimTK::SpatialVec > &bodyForces, SimTK::Vector &generalizedForce) const override
 Force interface applies tension to bodies, and Muscle also checks that applied muscle tension is not negative. More...
 
double computePotentialEnergy (const SimTK::State &state) const override
 Potential energy stored by the muscle. More...
 
SimTK::Vec3 computePathColor (const SimTK::State &state) const override
 Override PathActuator virtual to calculate a preferred color for the muscle path based on activation. More...
 
void extendConnectToModel (Model &aModel) override
 Model Component creation interface. More...
 
void extendAddToSystem (SimTK::MultibodySystem &system) const override
 Add appropriate Simbody elements (if needed) to the System corresponding to this component and specify needed state resources. More...
 
void extendSetPropertiesFromState (const SimTK::State &s) override
 Subclass should override; be sure to invoke Force::extendSetPropertiesFromState() at the beginning of the overriding method. 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...
 
virtual void updateGeometry (const SimTK::State &s)
 
- Protected Member Functions inherited from OpenSim::PathActuator
void extendRealizeDynamics (const SimTK::State &state) const override
 Extension of parent class method; derived classes may extend further. More...
 
- Protected Member Functions inherited from OpenSim::ScalarActuator
double computeOverrideActuation (const SimTK::State &s) const
 
OpenSim::Array< std::string > getRecordLabels () const override
 Methods to query a actuation for the value actually applied during simulation. More...
 
OpenSim::Array< double > getRecordValues (const SimTK::State &state) const override
 Given SimTK::State object extract all the values necessary to report actuation, application location frame, etc. More...
 
- Protected Member Functions inherited from OpenSim::Force
 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 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...
 
- 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...
 
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...
 
- 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...
 
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 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...
 

Auto-generated functions

static Millard2012EquilibriumMusclesafeDownCast (OpenSim::Object *obj)
 For use in MATLAB and Python to access the concrete class. More...
 
static const std::string & getClassName ()
 This returns "Millard2012EquilibriumMuscle". More...
 
void assign (Object &aObject) override
 This allows copy assignment in the Java GUI. More...
 
Millard2012EquilibriumMuscleclone () const override
 Create a new heap-allocated copy of the concrete object to which this Object refers. More...
 
const std::string & getConcreteClassName () const override
 Returns the class name of the concrete Object-derived class of the actual object referenced by this Object, as a string. More...
 

Additional Inherited Members

- Static Public Member Functions inherited from OpenSim::Muscle
static MusclesafeDownCast (OpenSim::Object *obj)
 For use in MATLAB and Python to access the concrete class. More...
 
static const std::string & getClassName ()
 This returns "Muscle". More...
 
- Static Public Member Functions inherited from OpenSim::PathActuator
static PathActuatorsafeDownCast (OpenSim::Object *obj)
 For use in MATLAB and Python to access the concrete class. More...
 
static const std::string & getClassName ()
 This returns "PathActuator". More...
 
- Static Public Member Functions inherited from OpenSim::ScalarActuator
static ScalarActuatorsafeDownCast (OpenSim::Object *obj)
 For use in MATLAB and Python to access the concrete class. More...
 
static const std::string & getClassName ()
 This returns "ScalarActuator". More...
 
- Static Public Member Functions inherited from OpenSim::Actuator
static ActuatorsafeDownCast (OpenSim::Object *obj)
 For use in MATLAB and Python to access the concrete class. More...
 
static const std::string & getClassName ()
 This returns "Actuator". More...
 
- Static Public Member Functions inherited from OpenSim::Force
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...
 
- 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...
 
- Protected Attributes inherited from OpenSim::Muscle
double _muscleWidth
 The assumed fixed muscle-width from which the fiber pennation angle can be calculated. More...
 
double _maxIsometricForce
 to support deprecated muscles More...
 
double _optimalFiberLength
 
double _pennationAngleAtOptimal
 
double _tendonSlackLength
 
- Protected Attributes inherited from OpenSim::Actuator
int _controlIndex
 
- Protected Attributes inherited from OpenSim::Force
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...
 
- 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 class implements a configurable equilibrium muscle model, as described in Millard et al. (2013).

An equilibrium model assumes that the forces generated by the fiber and tendon are equal:

\[ f_{ISO}\Big(\mathbf{a}(t) \mathbf{f}_L(\hat{l}_{CE}) \mathbf{f}_V(\hat{v}_{CE}) + \mathbf{f}_{PE}(\hat{l}_{CE}) + \beta \hat{v}_{CE}\Big) \cos \phi - f_{ISO}\mathbf{f}_{SE}(\hat{l}_{T}) = 0 \]

fig_Millard2012EquilibriumMuscle.png

This model can be simulated in several configurations by adjusting three flags:

  • ignore_tendon_compliance: set to true to make the tendon rigid. This assumption is usually reasonable for short tendons, and can result in a performance improvement by eliminating high-frequency dynamics and removing the fiber length from the state vector.
  • ignore_activation_dynamics: set to true to use the excitation input as the activation signal. This results in faster simulations by reducing the size of the state vector.
  • fiber_damping: set to a value greater than 0.001 to include fiber damping in the model. The addition of damping reduces simulation time while allowing the muscle model to be more physiological (it can have an activation of zero, its active-force-length curve can go to zero, and its force-velocity curve can be asymptotic).

Elastic Tendon, No Fiber Damping

The most typical configuration used in the literature is to simulate a muscle with an elastic tendon, full fiber dynamics, and activation dynamics. The resulting formulation suffers from three singularities: \(\mathbf{a}(t) \rightarrow 0\), \(\phi \rightarrow 90^\circ\), and \( \mathbf{f}_L(\hat{l}_{CE}) \rightarrow 0 \). These situations are all handled in this model to ensure that it does not produce singularities and does not result in intolerably long simulation times.

Numerical singularities arise from the manner in which the equilibrium equation is rearranged to yield an ordinary differential equation (ODE). The above equation is rearranged to isolate \( \mathbf{f}_V(\hat{v}_{CE}) \). We then invert to solve for \( \hat{v}_{CE} \), which is then numerically integrated during a simulation:

\[ \hat{v}_{CE} = \mathbf{f}_V ^{-1} \Big( \frac{ ( \mathbf{f}_{SE}(\hat{l}_{T}) ) / \cos \phi - \mathbf{f}_{PE}(\hat{l}_{CE}) } { \mathbf{a}(t) \mathbf{f}_L(\hat{l}_{CE})} \Big) \]

The above equation becomes numerically stiff when terms in the denominator approach zero (when \(\mathbf{a}(t) \rightarrow 0\), \(\phi \rightarrow 90^\circ\), or \( \mathbf{f}_L(\hat{l}_{CE}) \rightarrow 0 \)) or, additionally, when the slope of \(\mathbf{f}_V ^{-1}\) is steep (which occurs at fiber velocities close to the maximum concentric and maximum eccentric fiber velocities).

Singularities can be managed by ensuring that the muscle model is always activated ( \(\mathbf{a}(t) > 0\)), the fiber will stop contracting when a pennation angle of 90 degrees is approached ( \(\phi < 90^\circ\)), and the fiber will also stop contracting as its length approaches a lower bound ( \( \hat{l}_{CE} > lowerbound\)), which is typically around half the fiber's resting length (to ensure \( \mathbf{f}_L(\hat{l}_{CE}) > 0 \)). The fiber is prevented from reaching unphysiological lengths or its maximum pennation angle using a unilateral constraint. Additionally, the force-velocity curve is modified so that it is invertible.

When an elastic tendon without fiber damping is selected, the minimum active-force-length value is set to 0.1, the minimum permissible activation is set to 0.01, and the maximum permissible pennation angle is set to acos(0.1) or 84.3 degrees. This is done as a convenience for the user to prevent the model from taking an unreasonable amount of time to simulate.

(Rigid Tendon) or (Elastic Tendon with Fiber Damping)

Neither of these formulations has any singularities. The lower bound of the active-force-length curve can be zero (min( \( \mathbf{f}_L(\hat{l}_{CE})) = 0 \)), activation can be zero (i.e., the muscle can be turned off completely), and the force-velocity curve need not be invertible.

The rigid tendon formulation removes the singularities by ignoring the elasticity of the tendon. This assumption is reasonable for many muscles, but it is up to the user to determine whether this assumption is valid.

The formulation that uses an elastic tendon with fiber damping removes singularities by solving the equilibrium equation with Newton's method. This is possible because the partial derivative of the equilibrium equation with respect to fiber velocity is always positive if \( \beta > 0\) and, thus, Newton's method can find a solution to the equilibrium equation.

When either of these singularity-free formulations is selected, the minimum active-force-length value and the minimum permissible activation are set to zero. This is done as a convenience for the user, as these changes make the results of the model more realistic yet incur no performance penalty. The maximum pennation angle is left as acos(0.1) or 84.3 degrees, as allowing higher pennation angles results in an increasingly stiff fiber velocity state as pennation angle increases.

Usage

This object should be updated through the set methods provided.

Example

double maxIsometricForce = 5000; //N
double optimalFiberLength = 0.025; //m
double tendonSlackLength = 0.25; //m
double pennationAngle = 0.5; //rad
bool ignoreTendonCompliance = false;
bool ignoreActivationDynamics = false;
double dampingCoefficient = 0.001;
Millard2012EquilibriumMuscle myMuscle("myMuscle",
maxIsometricForce,
optimalFiberLength,
tendonSlackLength,
pennationAngle);
myMuscle.setMuscleConfiguration(ignoreTendonCompliance,
ignoreActivationDynamics,
dampingCoefficient);

Please refer to the doxygen for more information on the properties that are objects themselves (MuscleFixedWidthPennationModel, ActiveForceLengthCurve, FiberForceLengthCurve, TendonForceLengthCurve, and ForceVelocityInverseCurve).

Reference

Millard, M., Uchida, T., Seth, A., Delp, S.L. (2013) Flexing computational muscle: modeling and simulation of musculotendon dynamics. ASME Journal of Biomechanical Engineering 135(2):021005. http://dx.doi.org/10.1115/1.4023390.

Author
Matt Millard
Tom Uchida
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

◆ Millard2012EquilibriumMuscle() [1/2]

OpenSim::Millard2012EquilibriumMuscle::Millard2012EquilibriumMuscle ( )

Default constructor.

Produces a non-functional empty muscle.

◆ Millard2012EquilibriumMuscle() [2/2]

OpenSim::Millard2012EquilibriumMuscle::Millard2012EquilibriumMuscle ( const std::string &  aName,
double  aMaxIsometricForce,
double  aOptimalFiberLength,
double  aTendonSlackLength,
double  aPennationAngle 
)

Constructs a functional muscle using default curves and activation model parameters.

The tendon is assumed to be elastic, full fiber dynamics are solved, and activation dynamics are included.

Parameters
aNameThe name of the muscle.
aMaxIsometricForceThe force generated by the muscle when fully activated at its optimal resting length with a contraction velocity of zero.
aOptimalFiberLengthThe optimal length of the muscle fiber.
aTendonSlackLengthThe resting length of the tendon.
aPennationAngleThe angle of the fiber (in radians) relative to the tendon when the fiber is at its optimal resting length.

Member Function Documentation

◆ assign()

void OpenSim::Millard2012EquilibriumMuscle::assign ( Object aObject)
inlineoverride

This allows copy assignment in the Java GUI.

Exceptions
Exceptionif the argument is not of type Millard2012EquilibriumMuscle.

◆ calcFiberVelocityInfo()

void OpenSim::Millard2012EquilibriumMuscle::calcFiberVelocityInfo ( const SimTK::State &  s,
FiberVelocityInfo fvi 
) const
overrideprotectedvirtual

Calculate the velocity-related values associated with the muscle state (fiber and tendon velocities, normalized velocities, pennation angular velocity, etc.).

Reimplemented from OpenSim::Muscle.

◆ calcMuscleDynamicsInfo()

void OpenSim::Millard2012EquilibriumMuscle::calcMuscleDynamicsInfo ( const SimTK::State &  s,
MuscleDynamicsInfo mdi 
) const
overrideprotectedvirtual

Calculate the dynamics-related values associated with the muscle state (from the active- and passive-force-length curves, the force-velocity curve, and the tendon-force-length curve).

The last entry is a SimTK::Vector containing the passive conservative (elastic) fiber force and the passive non-conservative (damping) fiber force.

Reimplemented from OpenSim::Muscle.

◆ calcMuscleLengthInfo()

void OpenSim::Millard2012EquilibriumMuscle::calcMuscleLengthInfo ( const SimTK::State &  s,
MuscleLengthInfo mli 
) const
overrideprotectedvirtual

Calculate the position-related values associated with the muscle state (fiber and tendon lengths, normalized lengths, pennation angle, etc.).

Reimplemented from OpenSim::Muscle.

◆ calcMusclePotentialEnergyInfo()

void OpenSim::Millard2012EquilibriumMuscle::calcMusclePotentialEnergyInfo ( const SimTK::State &  s,
MusclePotentialEnergyInfo mpei 
) const
overrideprotectedvirtual

Calculate the potential energy values associated with the muscle.

Reimplemented from OpenSim::Muscle.

◆ clone()

Millard2012EquilibriumMuscle* OpenSim::Millard2012EquilibriumMuscle::clone ( ) const
inlineoverridevirtual

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

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

Implements OpenSim::Muscle.

◆ computeActuation()

double OpenSim::Millard2012EquilibriumMuscle::computeActuation ( const SimTK::State &  s) const
finaloverridevirtual
Parameters
[in]sThe state of the system.
Returns
The tensile force the muscle is generating (N).

Implements OpenSim::Muscle.

◆ computeFiberEquilibrium()

void OpenSim::Millard2012EquilibriumMuscle::computeFiberEquilibrium ( SimTK::State &  s,
bool  solveForVelocity = false 
) const

Computes the fiber length such that the fiber and tendon are developing the same force, either assuming muscle-tendon velocity as provided by the state or zero as designated by the useZeroVelocity flag.

Parameters
[in,out]sThe state of the system.
solveForVelocityFlag indicating to solve for fiber velocity, which by default is false (zero fiber-velocity)
Exceptions
MuscleCannotEquilibrate

◆ computeInitialFiberEquilibrium()

void OpenSim::Millard2012EquilibriumMuscle::computeInitialFiberEquilibrium ( SimTK::State &  s) const
inlineoverridevirtual

Computes the fiber length such that the fiber and tendon are developing the same force, distributing the velocity of the entire musculotendon actuator between the fiber and tendon according to their relative stiffnesses.

Parameters
[in,out]sThe state of the system.
Exceptions
MuscleCannotEquilibrate

Implements OpenSim::Muscle.

◆ computeStateVariableDerivatives()

void OpenSim::Millard2012EquilibriumMuscle::computeStateVariableDerivatives ( const SimTK::State &  s) const
overrideprotectedvirtual

Computes state variable derivatives.

Reimplemented from OpenSim::Component.

◆ extendAddToSystem()

void OpenSim::Millard2012EquilibriumMuscle::extendAddToSystem ( SimTK::MultibodySystem &  system) const
overrideprotectedvirtual

Creates the ModelComponent so that it can be used in simulation.

Reimplemented from OpenSim::Component.

◆ extendConnectToModel()

void OpenSim::Millard2012EquilibriumMuscle::extendConnectToModel ( Model model)
overrideprotectedvirtual

Sets up the ModelComponent from the model, if necessary.

Reimplemented from OpenSim::ModelComponent.

◆ extendInitStateFromProperties()

void OpenSim::Millard2012EquilibriumMuscle::extendInitStateFromProperties ( SimTK::State &  s) const
overrideprotectedvirtual

Initializes the state of the ModelComponent.

Reimplemented from OpenSim::Component.

◆ extendPostScale()

void OpenSim::Millard2012EquilibriumMuscle::extendPostScale ( const SimTK::State &  s,
const ScaleSet scaleSet 
)
overridevirtual

Adjust the properties of the muscle after the model has been scaled.

The optimal fiber length and tendon slack length are each multiplied by the ratio of the current path length and the path length before scaling.

Reimplemented from OpenSim::ModelComponent.

◆ extendSetPropertiesFromState()

void OpenSim::Millard2012EquilibriumMuscle::extendSetPropertiesFromState ( const SimTK::State &  s)
overrideprotectedvirtual

Sets the default state for the ModelComponent.

Reimplemented from OpenSim::Component.

◆ get_activation_time_constant()

const double& OpenSim::Millard2012EquilibriumMuscle::get_activation_time_constant ( ) const
inline

Get the value of the activation_time_constant property.

◆ get_ActiveForceLengthCurve()

const ActiveForceLengthCurve& OpenSim::Millard2012EquilibriumMuscle::get_ActiveForceLengthCurve ( ) const
inline

Get the value of the ActiveForceLengthCurve property.

◆ get_deactivation_time_constant()

const double& OpenSim::Millard2012EquilibriumMuscle::get_deactivation_time_constant ( ) const
inline

Get the value of the deactivation_time_constant property.

◆ get_default_activation()

const double& OpenSim::Millard2012EquilibriumMuscle::get_default_activation ( ) const
inline

Get the value of the default_activation property.

◆ get_default_fiber_length()

const double& OpenSim::Millard2012EquilibriumMuscle::get_default_fiber_length ( ) const
inline

Get the value of the default_fiber_length property.

◆ get_fiber_damping()

const double& OpenSim::Millard2012EquilibriumMuscle::get_fiber_damping ( ) const
inline

Get the value of the fiber_damping property.

◆ get_FiberForceLengthCurve()

const FiberForceLengthCurve& OpenSim::Millard2012EquilibriumMuscle::get_FiberForceLengthCurve ( ) const
inline

Get the value of the FiberForceLengthCurve property.

◆ get_ForceVelocityCurve()

const ForceVelocityCurve& OpenSim::Millard2012EquilibriumMuscle::get_ForceVelocityCurve ( ) const
inline

Get the value of the ForceVelocityCurve property.

◆ get_maximum_pennation_angle()

const double& OpenSim::Millard2012EquilibriumMuscle::get_maximum_pennation_angle ( ) const
inline

Get the value of the maximum_pennation_angle property.

◆ get_minimum_activation()

const double& OpenSim::Millard2012EquilibriumMuscle::get_minimum_activation ( ) const
inline

Get the value of the minimum_activation property.

◆ get_TendonForceLengthCurve()

const TendonForceLengthCurve& OpenSim::Millard2012EquilibriumMuscle::get_TendonForceLengthCurve ( ) const
inline

Get the value of the TendonForceLengthCurve property.

◆ getActivationDerivative()

double OpenSim::Millard2012EquilibriumMuscle::getActivationDerivative ( const SimTK::State &  s) const
Parameters
sThe state of the system.
Returns
The time derivative of activation.

◆ getActivationModel()

const MuscleFirstOrderActivationDynamicModel& OpenSim::Millard2012EquilibriumMuscle::getActivationModel ( ) const
Returns
The MuscleFirstOrderActivationDynamicModel owned by this model.

◆ getActivationTimeConstant()

double OpenSim::Millard2012EquilibriumMuscle::getActivationTimeConstant ( ) const
Returns
The activation time constant (in seconds).

◆ getActiveForceLengthCurve()

const ActiveForceLengthCurve& OpenSim::Millard2012EquilibriumMuscle::getActiveForceLengthCurve ( ) const
Returns
The ActiveForceLengthCurve used by this model.

◆ getClassName()

static const std::string& OpenSim::Millard2012EquilibriumMuscle::getClassName ( )
inlinestatic

This returns "Millard2012EquilibriumMuscle".

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::Millard2012EquilibriumMuscle::getConcreteClassName ( ) const
inlineoverridevirtual

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

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

See also
getClassName()

Implements OpenSim::Muscle.

◆ getDeactivationTimeConstant()

double OpenSim::Millard2012EquilibriumMuscle::getDeactivationTimeConstant ( ) const
Returns
The deactivation time constant (in seconds).

◆ getDefaultActivation()

double OpenSim::Millard2012EquilibriumMuscle::getDefaultActivation ( ) const
Returns
The default activation level that is used as an initial condition if none is provided by the user.

◆ getDefaultFiberLength()

double OpenSim::Millard2012EquilibriumMuscle::getDefaultFiberLength ( ) const
Returns
The default fiber length that is used as an initial condition if none is provided by the user.

◆ getFiberDamping()

double OpenSim::Millard2012EquilibriumMuscle::getFiberDamping ( ) const
Returns
The fiber damping coefficient.

◆ getFiberForceLengthCurve()

const FiberForceLengthCurve& OpenSim::Millard2012EquilibriumMuscle::getFiberForceLengthCurve ( ) const
Returns
The FiberForceLengthCurve used by this model.

◆ getFiberStiffnessAlongTendon()

double OpenSim::Millard2012EquilibriumMuscle::getFiberStiffnessAlongTendon ( const SimTK::State &  s) const
Returns
The stiffness of the muscle fibers along the tendon (N/m).

◆ getFiberVelocity()

double OpenSim::Millard2012EquilibriumMuscle::getFiberVelocity ( const SimTK::State &  s) const
Parameters
sThe state of the system.
Returns
The velocity of the fiber (m/s).

◆ getForceVelocityCurve()

const ForceVelocityCurve& OpenSim::Millard2012EquilibriumMuscle::getForceVelocityCurve ( ) const
Returns
The ForceVelocityCurve used by this model.

◆ getMinimumActivation()

double OpenSim::Millard2012EquilibriumMuscle::getMinimumActivation ( ) const
Returns
The minimum activation level permitted by the muscle model. Note that this equilibrium model, like all equilibrium models, has a singularity when activation approaches 0, which means that a non-zero lower bound is required.

◆ getMinimumFiberLength()

double OpenSim::Millard2012EquilibriumMuscle::getMinimumFiberLength ( ) const
Returns
The minimum fiber length, which is the maximum of two values: the smallest fiber length allowed by the pennation model, and the minimum fiber length on the active-force-length curve. When the fiber reaches this length, it is constrained to this value until the fiber velocity becomes positive.

◆ getMinimumFiberLengthAlongTendon()

double OpenSim::Millard2012EquilibriumMuscle::getMinimumFiberLengthAlongTendon ( ) const
Returns
The minimum fiber length along the tendon, which is the maximum of two values: the smallest fiber length along the tendon permitted by the pennation model, and the minimum fiber length along the tendon on the active-force-length curve. When the fiber length reaches this value, it is constrained to this length along the tendon until the fiber velocity becomes positive.

◆ getPassiveFiberDampingForce()

double OpenSim::Millard2012EquilibriumMuscle::getPassiveFiberDampingForce ( const SimTK::State &  s) const

get the portion of the passive fiber force generated by the damping element only (N)

◆ getPassiveFiberDampingForceAlongTendon()

double OpenSim::Millard2012EquilibriumMuscle::getPassiveFiberDampingForceAlongTendon ( const SimTK::State &  s) const

get the portion of the passive fiber force generated by the damping element only, projected onto the tendon direction (N)

◆ getPassiveFiberElasticForce()

double OpenSim::Millard2012EquilibriumMuscle::getPassiveFiberElasticForce ( const SimTK::State &  s) const

get the portion of the passive fiber force generated by the elastic element only (N)

◆ getPassiveFiberElasticForceAlongTendon()

double OpenSim::Millard2012EquilibriumMuscle::getPassiveFiberElasticForceAlongTendon ( const SimTK::State &  s) const

get the portion of the passive fiber force generated by the elastic element only, projected onto the tendon direction (N)

◆ getPennationModel()

const MuscleFixedWidthPennationModel& OpenSim::Millard2012EquilibriumMuscle::getPennationModel ( ) const
Returns
The MuscleFixedWidthPennationModel owned by this model.

◆ getStateVariableDeriv()

double OpenSim::Millard2012EquilibriumMuscle::getStateVariableDeriv ( const SimTK::State &  s,
const std::string &  aStateName 
) const
protected

Gets the derivative of an actuator state by index.

Parameters
sThe state.
aStateNameThe name of the state to get.
Returns
The value of the state derivative.

◆ getTendonForceLengthCurve()

const TendonForceLengthCurve& OpenSim::Millard2012EquilibriumMuscle::getTendonForceLengthCurve ( ) const
Returns
The TendonForceLengthCurve used by this model.

◆ getTendonForceMultiplier()

double OpenSim::Millard2012EquilibriumMuscle::getTendonForceMultiplier ( SimTK::State &  s) const
Parameters
sThe state of the system.
Returns
The normalized force term associated with the tendon element, \(\mathbf{f}_{SE}(\hat{l}_{T})\), in the equilibrium equation.

◆ getUseFiberDamping()

bool OpenSim::Millard2012EquilibriumMuscle::getUseFiberDamping ( ) const
Returns
A boolean indicating whether fiber damping is being used.

◆ safeDownCast()

static Millard2012EquilibriumMuscle* OpenSim::Millard2012EquilibriumMuscle::safeDownCast ( OpenSim::Object obj)
inlinestatic

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

Example: cObj = Millard2012EquilibriumMuscle.safeDownCast(obj). This is equivalent to dynamic_cast<Millard2012EquilibriumMuscle*>(obj) in C++.

◆ set_activation_time_constant()

void OpenSim::Millard2012EquilibriumMuscle::set_activation_time_constant ( const double &  value)
inline

Set the value of the activation_time_constant property.

◆ set_ActiveForceLengthCurve()

void OpenSim::Millard2012EquilibriumMuscle::set_ActiveForceLengthCurve ( const ActiveForceLengthCurve value)
inline

Set the value of the ActiveForceLengthCurve property.

◆ set_deactivation_time_constant()

void OpenSim::Millard2012EquilibriumMuscle::set_deactivation_time_constant ( const double &  value)
inline

Set the value of the deactivation_time_constant property.

◆ set_default_activation()

void OpenSim::Millard2012EquilibriumMuscle::set_default_activation ( const double &  value)
inline

Set the value of the default_activation property.

◆ set_default_fiber_length()

void OpenSim::Millard2012EquilibriumMuscle::set_default_fiber_length ( const double &  value)
inline

Set the value of the default_fiber_length property.

◆ set_fiber_damping()

void OpenSim::Millard2012EquilibriumMuscle::set_fiber_damping ( const double &  value)
inline

Set the value of the fiber_damping property.

◆ set_FiberForceLengthCurve()

void OpenSim::Millard2012EquilibriumMuscle::set_FiberForceLengthCurve ( const FiberForceLengthCurve value)
inline

Set the value of the FiberForceLengthCurve property.

◆ set_ForceVelocityCurve()

void OpenSim::Millard2012EquilibriumMuscle::set_ForceVelocityCurve ( const ForceVelocityCurve value)
inline

Set the value of the ForceVelocityCurve property.

◆ set_maximum_pennation_angle()

void OpenSim::Millard2012EquilibriumMuscle::set_maximum_pennation_angle ( const double &  value)
inline

Set the value of the maximum_pennation_angle property.

◆ set_minimum_activation()

void OpenSim::Millard2012EquilibriumMuscle::set_minimum_activation ( const double &  value)
inline

Set the value of the minimum_activation property.

◆ set_TendonForceLengthCurve()

void OpenSim::Millard2012EquilibriumMuscle::set_TendonForceLengthCurve ( const TendonForceLengthCurve value)
inline

Set the value of the TendonForceLengthCurve property.

◆ setActivation()

void OpenSim::Millard2012EquilibriumMuscle::setActivation ( SimTK::State &  s,
double  activation 
) const
overridevirtual
Parameters
sThe state of the system.
activationThe desired activation level.

Implements OpenSim::Muscle.

◆ setActivationTimeConstant()

void OpenSim::Millard2012EquilibriumMuscle::setActivationTimeConstant ( double  activationTimeConstant)
Parameters
activationTimeConstantThe activation time constant (in seconds).

◆ setActiveForceLengthCurve()

void OpenSim::Millard2012EquilibriumMuscle::setActiveForceLengthCurve ( ActiveForceLengthCurve aActiveForceLengthCurve)
Parameters
aActiveForceLengthCurveThe ActiveForceLengthCurve used by the muscle model to scale active fiber force as a function of fiber length.

◆ setDeactivationTimeConstant()

void OpenSim::Millard2012EquilibriumMuscle::setDeactivationTimeConstant ( double  deactivationTimeConstant)
Parameters
deactivationTimeConstantThe deactivation time constant (in seconds).

◆ setDefaultActivation()

void OpenSim::Millard2012EquilibriumMuscle::setDefaultActivation ( double  activation)
Parameters
activationThe default activation level that is used to initialize the muscle.

◆ setDefaultFiberLength()

void OpenSim::Millard2012EquilibriumMuscle::setDefaultFiberLength ( double  fiberLength)
Parameters
fiberLengthThe default fiber length that is used to initialize the muscle.

◆ setFiberDamping()

void OpenSim::Millard2012EquilibriumMuscle::setFiberDamping ( double  dampingCoefficient)
Parameters
dampingCoefficientDefine the fiber damping coefficient.

◆ setFiberForceLengthCurve()

void OpenSim::Millard2012EquilibriumMuscle::setFiberForceLengthCurve ( FiberForceLengthCurve aFiberForceLengthCurve)
Parameters
aFiberForceLengthCurveThe FiberForceLengthCurve used by the muscle model to calculate the passive force the muscle fiber generates as a function of fiber length.

◆ setFiberLength()

void OpenSim::Millard2012EquilibriumMuscle::setFiberLength ( SimTK::State &  s,
double  fiberLength 
) const
Parameters
[out]sThe state of the system.
fiberLengthThe desired fiber length (m).

◆ setForceVelocityCurve()

void OpenSim::Millard2012EquilibriumMuscle::setForceVelocityCurve ( ForceVelocityCurve aForceVelocityCurve)
Parameters
aForceVelocityCurveThe ForceVelocityCurve used by the muscle model to calculate the derivative of fiber length.

◆ setMinimumActivation()

void OpenSim::Millard2012EquilibriumMuscle::setMinimumActivation ( double  minimumActivation)
Parameters
minimumActivationThe minimum permissible activation level.

◆ setMuscleConfiguration()

void OpenSim::Millard2012EquilibriumMuscle::setMuscleConfiguration ( bool  ignoreTendonCompliance,
bool  ignoreActivationDynamics,
double  dampingCoefficient 
)
Parameters
ignoreTendonComplianceUse a rigid (true) or elastic tendon.
ignoreActivationDynamicsTreat the excitation input as the activation signal (true) or use a first-order activation dynamic model.
dampingCoefficientSpecify the amount of damping to include in the model (must be either 0 or greater than 0.001).

◆ setStateVariableDeriv()

void OpenSim::Millard2012EquilibriumMuscle::setStateVariableDeriv ( const SimTK::State &  s,
const std::string &  aStateName,
double  aValue 
) const
protected

Sets the derivative of an actuator state specified by name.

Parameters
sThe state.
aStateNameThe name of the state to set.
aValueThe value to which the state should be set.

◆ setTendonForceLengthCurve()

void OpenSim::Millard2012EquilibriumMuscle::setTendonForceLengthCurve ( TendonForceLengthCurve aTendonForceLengthCurve)
Parameters
aTendonForceLengthCurveThe TendonForceLengthCurve used by the muscle model to calculate the force exerted by the tendon as a function of tendon length.

◆ upd_activation_time_constant()

double& OpenSim::Millard2012EquilibriumMuscle::upd_activation_time_constant ( )
inline

Get a writable reference to the activation_time_constant property.

◆ upd_ActiveForceLengthCurve()

ActiveForceLengthCurve& OpenSim::Millard2012EquilibriumMuscle::upd_ActiveForceLengthCurve ( )
inline

Get a writable reference to the ActiveForceLengthCurve property.

◆ upd_deactivation_time_constant()

double& OpenSim::Millard2012EquilibriumMuscle::upd_deactivation_time_constant ( )
inline

Get a writable reference to the deactivation_time_constant property.

◆ upd_default_activation()

double& OpenSim::Millard2012EquilibriumMuscle::upd_default_activation ( )
inline

Get a writable reference to the default_activation property.

◆ upd_default_fiber_length()

double& OpenSim::Millard2012EquilibriumMuscle::upd_default_fiber_length ( )
inline

Get a writable reference to the default_fiber_length property.

◆ upd_fiber_damping()

double& OpenSim::Millard2012EquilibriumMuscle::upd_fiber_damping ( )
inline

Get a writable reference to the fiber_damping property.

◆ upd_FiberForceLengthCurve()

FiberForceLengthCurve& OpenSim::Millard2012EquilibriumMuscle::upd_FiberForceLengthCurve ( )
inline

Get a writable reference to the FiberForceLengthCurve property.

◆ upd_ForceVelocityCurve()

ForceVelocityCurve& OpenSim::Millard2012EquilibriumMuscle::upd_ForceVelocityCurve ( )
inline

Get a writable reference to the ForceVelocityCurve property.

◆ upd_maximum_pennation_angle()

double& OpenSim::Millard2012EquilibriumMuscle::upd_maximum_pennation_angle ( )
inline

Get a writable reference to the maximum_pennation_angle property.

◆ upd_minimum_activation()

double& OpenSim::Millard2012EquilibriumMuscle::upd_minimum_activation ( )
inline

Get a writable reference to the minimum_activation property.

◆ upd_TendonForceLengthCurve()

TendonForceLengthCurve& OpenSim::Millard2012EquilibriumMuscle::upd_TendonForceLengthCurve ( )
inline

Get a writable reference to the TendonForceLengthCurve property.

OpenSim Property, Socket, Output, Input Documentation

◆ activation_time_constant

double OpenSim::Millard2012EquilibriumMuscle::activation_time_constant

"Activation time constant (in seconds)."

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

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

◆ ActiveForceLengthCurve

ActiveForceLengthCurve OpenSim::Millard2012EquilibriumMuscle::ActiveForceLengthCurve

"Active-force-length curve."

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

See also
get_ActiveForceLengthCurve(), upd_ActiveForceLengthCurve(), set_ActiveForceLengthCurve()

◆ deactivation_time_constant

double OpenSim::Millard2012EquilibriumMuscle::deactivation_time_constant

"Deactivation time constant (in seconds)."

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

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

◆ default_activation

double OpenSim::Millard2012EquilibriumMuscle::default_activation

"Assumed initial activation level if none is assigned."

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

See also
get_default_activation(), upd_default_activation(), set_default_activation()

◆ default_fiber_length

double OpenSim::Millard2012EquilibriumMuscle::default_fiber_length

"Assumed initial fiber length if none is assigned."

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

See also
get_default_fiber_length(), upd_default_fiber_length(), set_default_fiber_length()

◆ fiber_damping

double OpenSim::Millard2012EquilibriumMuscle::fiber_damping

"The linear damping of the fiber."

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

See also
get_fiber_damping(), upd_fiber_damping(), set_fiber_damping()

◆ FiberForceLengthCurve

FiberForceLengthCurve OpenSim::Millard2012EquilibriumMuscle::FiberForceLengthCurve

"Passive-force-length curve."

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

See also
get_FiberForceLengthCurve(), upd_FiberForceLengthCurve(), set_FiberForceLengthCurve()

◆ ForceVelocityCurve

ForceVelocityCurve OpenSim::Millard2012EquilibriumMuscle::ForceVelocityCurve

"Force-velocity curve."

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

See also
get_ForceVelocityCurve(), upd_ForceVelocityCurve(), set_ForceVelocityCurve()

◆ maximum_pennation_angle

double OpenSim::Millard2012EquilibriumMuscle::maximum_pennation_angle

"Maximum pennation angle (in radians)."

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

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

◆ minimum_activation

double OpenSim::Millard2012EquilibriumMuscle::minimum_activation

"Activation lower bound."

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

See also
get_minimum_activation(), upd_minimum_activation(), set_minimum_activation()

◆ passive_fiber_damping_force

double OpenSim::Millard2012EquilibriumMuscle::passive_fiber_damping_force

Provides the value of getPassiveFiberDampingForce() and is available at stage SimTK::Stage::Dynamics .

This output was generated with the OpenSim_DECLARE_OUTPUT macro.

◆ passive_fiber_damping_force_along_tendon

double OpenSim::Millard2012EquilibriumMuscle::passive_fiber_damping_force_along_tendon

Provides the value of getPassiveFiberDampingForceAlongTendon() and is available at stage SimTK::Stage::Dynamics .

This output was generated with the OpenSim_DECLARE_OUTPUT macro.

◆ passive_fiber_elastic_force

double OpenSim::Millard2012EquilibriumMuscle::passive_fiber_elastic_force

Provides the value of getPassiveFiberElasticForce() and is available at stage SimTK::Stage::Dynamics .

This output was generated with the OpenSim_DECLARE_OUTPUT macro.

◆ passive_fiber_elastic_force_along_tendon

double OpenSim::Millard2012EquilibriumMuscle::passive_fiber_elastic_force_along_tendon

Provides the value of getPassiveFiberElasticForceAlongTendon() and is available at stage SimTK::Stage::Dynamics .

This output was generated with the OpenSim_DECLARE_OUTPUT macro.

◆ TendonForceLengthCurve

TendonForceLengthCurve OpenSim::Millard2012EquilibriumMuscle::TendonForceLengthCurve

"Tendon-force-length curve."

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

See also
get_TendonForceLengthCurve(), upd_TendonForceLengthCurve(), set_TendonForceLengthCurve()

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