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| Millard2012EquilibriumMuscle () |
| Default constructor. More...
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| 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...
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bool | getUseFiberDamping () const |
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double | getFiberDamping () const |
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double | getDefaultActivation () const |
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double | getDefaultFiberLength () const |
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double | getActivationTimeConstant () const |
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double | getDeactivationTimeConstant () const |
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double | getMinimumActivation () const |
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const ActiveForceLengthCurve & | getActiveForceLengthCurve () const |
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const ForceVelocityCurve & | getForceVelocityCurve () const |
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const FiberForceLengthCurve & | getFiberForceLengthCurve () const |
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const TendonForceLengthCurve & | getTendonForceLengthCurve () const |
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const MuscleFixedWidthPennationModel & | getPennationModel () const |
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const MuscleFirstOrderActivationDynamicModel & | getActivationModel () const |
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double | getMinimumFiberLength () const |
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double | getMinimumFiberLengthAlongTendon () const |
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double | getTendonForceMultiplier (SimTK::State &s) const |
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double | getFiberStiffnessAlongTendon (const SimTK::State &s) const |
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double | getFiberVelocity (const SimTK::State &s) const |
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double | getActivationDerivative (const SimTK::State &s) const |
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double | getPassiveFiberElasticForce (const SimTK::State &s) const |
| get the portion of the passive fiber force generated by the elastic element only (N) More...
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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...
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double | getPassiveFiberDampingForce (const SimTK::State &s) const |
| get the portion of the passive fiber force generated by the damping element only (N) More...
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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...
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void | setMuscleConfiguration (bool ignoreTendonCompliance, bool ignoreActivationDynamics, double dampingCoefficient) |
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void | setFiberDamping (double dampingCoefficient) |
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void | setDefaultActivation (double activation) |
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void | setActivation (SimTK::State &s, double activation) const override |
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void | setDefaultFiberLength (double fiberLength) |
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void | setActivationTimeConstant (double activationTimeConstant) |
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void | setDeactivationTimeConstant (double deactivationTimeConstant) |
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void | setMinimumActivation (double minimumActivation) |
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void | setActiveForceLengthCurve (ActiveForceLengthCurve &aActiveForceLengthCurve) |
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void | setForceVelocityCurve (ForceVelocityCurve &aForceVelocityCurve) |
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void | setFiberForceLengthCurve (FiberForceLengthCurve &aFiberForceLengthCurve) |
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void | setTendonForceLengthCurve (TendonForceLengthCurve &aTendonForceLengthCurve) |
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void | setFiberLength (SimTK::State &s, double fiberLength) const |
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double | computeActuation (const SimTK::State &s) const override final |
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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...
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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...
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void | extendPostScale (const SimTK::State &s, const ScaleSet &scaleSet) override |
| Adjust the properties of the muscle after the model has been scaled. More...
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const double & | get_fiber_damping () const |
| Get the value of the fiber_damping property. More...
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double & | upd_fiber_damping () |
| Get a writable reference to the fiber_damping property. More...
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void | set_fiber_damping (const double &value) |
| Set the value of the fiber_damping property. More...
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const double & | get_default_activation () const |
| Get the value of the default_activation property. More...
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double & | upd_default_activation () |
| Get a writable reference to the default_activation property. More...
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void | set_default_activation (const double &value) |
| Set the value of the default_activation property. More...
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const double & | get_default_fiber_length () const |
| Get the value of the default_fiber_length property. More...
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double & | upd_default_fiber_length () |
| Get a writable reference to the default_fiber_length property. More...
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void | set_default_fiber_length (const double &value) |
| Set the value of the default_fiber_length property. More...
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const double & | get_activation_time_constant () const |
| Get the value of the activation_time_constant property. More...
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double & | upd_activation_time_constant () |
| Get a writable reference to the activation_time_constant property. More...
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void | set_activation_time_constant (const double &value) |
| Set the value of the activation_time_constant property. More...
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const double & | get_deactivation_time_constant () const |
| Get the value of the deactivation_time_constant property. More...
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double & | upd_deactivation_time_constant () |
| Get a writable reference to the deactivation_time_constant property. More...
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void | set_deactivation_time_constant (const double &value) |
| Set the value of the deactivation_time_constant property. More...
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const double & | get_minimum_activation () const |
| Get the value of the minimum_activation property. More...
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double & | upd_minimum_activation () |
| Get a writable reference to the minimum_activation property. More...
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void | set_minimum_activation (const double &value) |
| Set the value of the minimum_activation property. More...
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const double & | get_maximum_pennation_angle () const |
| Get the value of the maximum_pennation_angle property. More...
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double & | upd_maximum_pennation_angle () |
| Get a writable reference to the maximum_pennation_angle property. More...
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void | set_maximum_pennation_angle (const double &value) |
| Set the value of the maximum_pennation_angle property. More...
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const ActiveForceLengthCurve & | get_ActiveForceLengthCurve () const |
| Get the value of the ActiveForceLengthCurve property. More...
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ActiveForceLengthCurve & | upd_ActiveForceLengthCurve () |
| Get a writable reference to the ActiveForceLengthCurve property. More...
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void | set_ActiveForceLengthCurve (const ActiveForceLengthCurve &value) |
| Set the value of the ActiveForceLengthCurve property. More...
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const ForceVelocityCurve & | get_ForceVelocityCurve () const |
| Get the value of the ForceVelocityCurve property. More...
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ForceVelocityCurve & | upd_ForceVelocityCurve () |
| Get a writable reference to the ForceVelocityCurve property. More...
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void | set_ForceVelocityCurve (const ForceVelocityCurve &value) |
| Set the value of the ForceVelocityCurve property. More...
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const FiberForceLengthCurve & | get_FiberForceLengthCurve () const |
| Get the value of the FiberForceLengthCurve property. More...
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FiberForceLengthCurve & | upd_FiberForceLengthCurve () |
| Get a writable reference to the FiberForceLengthCurve property. More...
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void | set_FiberForceLengthCurve (const FiberForceLengthCurve &value) |
| Set the value of the FiberForceLengthCurve property. More...
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const TendonForceLengthCurve & | get_TendonForceLengthCurve () const |
| Get the value of the TendonForceLengthCurve property. More...
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TendonForceLengthCurve & | upd_TendonForceLengthCurve () |
| Get a writable reference to the TendonForceLengthCurve property. More...
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void | set_TendonForceLengthCurve (const TendonForceLengthCurve &value) |
| Set the value of the TendonForceLengthCurve property. More...
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const double & | get_max_isometric_force () const |
| Get the value of the max_isometric_force property. More...
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double & | upd_max_isometric_force () |
| Get a writable reference to the max_isometric_force property. More...
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void | set_max_isometric_force (const double &value) |
| Set the value of the max_isometric_force property. More...
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const double & | get_optimal_fiber_length () const |
| Get the value of the optimal_fiber_length property. More...
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double & | upd_optimal_fiber_length () |
| Get a writable reference to the optimal_fiber_length property. More...
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void | set_optimal_fiber_length (const double &value) |
| Set the value of the optimal_fiber_length property. More...
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const double & | get_tendon_slack_length () const |
| Get the value of the tendon_slack_length property. More...
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double & | upd_tendon_slack_length () |
| Get a writable reference to the tendon_slack_length property. More...
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void | set_tendon_slack_length (const double &value) |
| Set the value of the tendon_slack_length property. More...
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const double & | get_pennation_angle_at_optimal () const |
| Get the value of the pennation_angle_at_optimal property. More...
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double & | upd_pennation_angle_at_optimal () |
| Get a writable reference to the pennation_angle_at_optimal property. More...
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void | set_pennation_angle_at_optimal (const double &value) |
| Set the value of the pennation_angle_at_optimal property. More...
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const double & | get_max_contraction_velocity () const |
| Get the value of the max_contraction_velocity property. More...
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double & | upd_max_contraction_velocity () |
| Get a writable reference to the max_contraction_velocity property. More...
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void | set_max_contraction_velocity (const double &value) |
| Set the value of the max_contraction_velocity property. More...
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const bool & | get_ignore_tendon_compliance () const |
| Get the value of the ignore_tendon_compliance property. More...
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bool & | upd_ignore_tendon_compliance () |
| Get a writable reference to the ignore_tendon_compliance property. More...
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void | set_ignore_tendon_compliance (const bool &value) |
| Set the value of the ignore_tendon_compliance property. More...
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const bool & | get_ignore_activation_dynamics () const |
| Get the value of the ignore_activation_dynamics property. More...
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bool & | upd_ignore_activation_dynamics () |
| Get a writable reference to the ignore_activation_dynamics property. More...
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void | set_ignore_activation_dynamics (const bool &value) |
| Set the value of the ignore_activation_dynamics property. More...
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| Muscle () |
| Default constructor. More...
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double | getMaxIsometricForce () const |
| get/set the maximum isometric force (in N) that the fibers can generate More...
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void | setMaxIsometricForce (double maxIsometricForce) |
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double | getOptimalFiberLength () const |
| get/set the optimal length (in m) of the muscle fibers (lumped as a single fiber) More...
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void | setOptimalFiberLength (double optimalFiberLength) |
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double | getTendonSlackLength () const |
| get/set the resting (slack) length (in m) of the tendon that is in series with the muscle fiber More...
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void | setTendonSlackLength (double tendonSlackLength) |
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double | getPennationAngleAtOptimalFiberLength () const |
| get/set the angle (in radians) between fibers at their optimal fiber length and the tendon More...
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void | setPennationAngleAtOptimalFiberLength (double pennationAngle) |
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double | getMaxContractionVelocity () const |
| get/set the maximum contraction velocity of the fibers, in optimal fiber-lengths per second More...
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void | setMaxContractionVelocity (double maxContractionVelocity) |
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bool | getIgnoreTendonCompliance (const SimTK::State &s) const |
| Get/set Modeling (runtime) option to ignore tendon compliance when computing muscle dynamics. More...
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void | setIgnoreTendonCompliance (SimTK::State &s, bool ignore) const |
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bool | getIgnoreActivationDynamics (const SimTK::State &s) const |
| Get/set Modeling (runtime) option to ignore activation dynamics when computing muscle dynamics. More...
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void | setIgnoreActivationDynamics (SimTK::State &s, bool ignore) const |
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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...
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double | getFiberLength (const SimTK::State &s) const |
| get the current working fiber length (m) for the muscle More...
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double | getPennationAngle (const SimTK::State &s) const |
| get the current pennation angle (radians) between the fiber and tendon at the current fiber length More...
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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...
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double | getTendonLength (const SimTK::State &s) const |
| get the current tendon length (m) given the current joint angles and fiber length More...
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double | getNormalizedFiberLength (const SimTK::State &s) const |
| get the current normalized fiber length (fiber_length/optimal_fiber_length) More...
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double | getFiberLengthAlongTendon (const SimTK::State &s) const |
| get the current fiber length (m) projected (*cos(pennationAngle)) onto the tendon direction More...
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double | getTendonStrain (const SimTK::State &s) const |
| get the current tendon strain (delta_l/tendon_slack_length is dimensionless) More...
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double | getFiberPotentialEnergy (const SimTK::State &s) const |
| the potential energy (J) stored in the fiber due to its parallel elastic element More...
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double | getTendonPotentialEnergy (const SimTK::State &s) const |
| the potential energy (J) stored in the tendon More...
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double | getMusclePotentialEnergy (const SimTK::State &s) const |
| the total potential energy (J) stored in the muscle More...
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double | getPassiveForceMultiplier (const SimTK::State &s) const |
| get the passive fiber (parallel elastic element) force multiplier More...
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double | getActiveForceLengthMultiplier (const SimTK::State &s) const |
| get the active fiber (contractile element) force multiplier due to current fiber length More...
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double | getFiberVelocity (const SimTK::State &s) const |
| get current fiber velocity (m/s) positive is lengthening More...
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double | getNormalizedFiberVelocity (const SimTK::State &s) const |
| get normalized fiber velocity. More...
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double | getFiberVelocityAlongTendon (const SimTK::State &s) const |
| get the current fiber velocity (m/s) projected onto the tendon direction More...
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double | getPennationAngularVelocity (const SimTK::State &s) const |
| get pennation angular velocity (radians/s) More...
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double | getTendonVelocity (const SimTK::State &s) const |
| get the tendon velocity (m/s) positive is lengthening More...
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double | getForceVelocityMultiplier (const SimTK::State &s) const |
| get the dimensionless multiplier resulting from the fiber's force-velocity curve More...
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double | getFiberForce (const SimTK::State &s) const |
| get the current fiber force (N) applied to the tendon More...
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double | getFiberForceAlongTendon (const SimTK::State &s) const |
| get the force of the fiber (N/m) along the direction of the tendon More...
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double | getActiveFiberForce (const SimTK::State &s) const |
| get the current active fiber force (N) due to activation*force_length*force_velocity relationships More...
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double | getPassiveFiberForce (const SimTK::State &s) const |
| get the total force applied by all passive elements in the fiber (N) More...
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double | getActiveFiberForceAlongTendon (const SimTK::State &s) const |
| get the current active fiber force (N) projected onto the tendon direction More...
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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...
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double | getTendonForce (const SimTK::State &s) const |
| get the current tendon force (N) applied to bones More...
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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...
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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...
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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...
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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...
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double | getFiberActivePower (const SimTK::State &s) const |
| get the current active fiber power (W) More...
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double | getFiberPassivePower (const SimTK::State &s) const |
| get the current passive fiber power (W) More...
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double | getTendonPower (const SimTK::State &s) const |
| get the current tendon power (W) More...
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double | getMusclePower (const SimTK::State &s) const |
| get the current muscle power (W) More...
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double | getStress (const SimTK::State &s) const override |
| get the stress in the muscle (part of the Actuator interface as well) More...
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void | setExcitation (SimTK::State &s, double excitation) const |
| set the excitation (control) for this muscle. More...
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double | getExcitation (const SimTK::State &s) const |
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void | computeEquilibrium (SimTK::State &s) const override final |
| Find and set the equilibrium state of the muscle (if any) More...
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void | assign (Object &aObject) override |
| This allows copy assignment in the Java GUI. More...
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| PathActuator () |
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AbstractGeometryPath & | updPath () |
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const AbstractGeometryPath & | getPath () const |
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template<typename PathType > |
PathType & | updPath () |
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template<typename PathType > |
const PathType & | getPath () const |
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template<typename PathType > |
PathType * | tryUpdPath () |
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template<typename PathType > |
const PathType * | tryGetPath () const |
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GeometryPath & | updGeometryPath () |
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const GeometryPath & | getGeometryPath () const |
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bool | hasVisualPath () const override |
| Return a flag indicating whether the Force is applied along a path that can be visualized. More...
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void | setOptimalForce (double aOptimalForce) |
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double | getOptimalForce () const override |
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virtual double | getLength (const SimTK::State &s) const |
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virtual double | getLengtheningSpeed (const SimTK::State &s) const |
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double | getSpeed (const SimTK::State &s) const final |
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double | getPower (const SimTK::State &s) const override |
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double | getStress (const SimTK::State &s) const override |
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void | addNewPathPoint (const std::string &proposedName, const PhysicalFrame &aBody, const SimTK::Vec3 &aPositionOnBody) |
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double | computeActuation (const SimTK::State &s) const override |
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virtual double | computeMomentArm (const SimTK::State &s, Coordinate &aCoord) const |
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const AbstractGeometryPath & | get_path () const |
| Get the value of the path property. More...
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AbstractGeometryPath & | upd_path () |
| Get a writable reference to the path property. More...
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void | set_path (const AbstractGeometryPath &value) |
| Set the value of the path property. More...
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const double & | get_optimal_force () const |
| Get the value of the optimal_force property. More...
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double & | upd_optimal_force () |
| Get a writable reference to the optimal_force property. More...
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void | set_optimal_force (const double &value) |
| Set the value of the optimal_force property. More...
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void | assign (Object &aObject) override |
| This allows copy assignment in the Java GUI. More...
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PathActuator * | clone () const override |
| Create a new heap-allocated copy of the concrete object to which this Object refers. More...
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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...
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| ScalarActuator () |
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virtual double | getControl (const SimTK::State &s) const |
| Convenience method to get control given scalar (double) valued control. More...
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int | numControls () const override |
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virtual void | setActuation (const SimTK::State &s, double aActuation) const |
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virtual double | getActuation (const SimTK::State &s) const |
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void | setMinControl (const double &aMinControl) |
| Methods to manage the bounds on ScalarActuator's control. More...
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double | getMinControl () const |
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void | setMaxControl (const double &aMaxControl) |
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double | getMaxControl () const |
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void | overrideActuation (SimTK::State &s, bool flag) const |
| Enable/disable a ScalarActuator's override actuation. More...
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bool | isActuationOverridden (const SimTK::State &s) const |
| return ScalarActuator's override status More...
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void | setOverrideActuation (SimTK::State &s, double value) const |
| set the actuation value used when the override is true More...
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double | getOverrideActuation (const SimTK::State &s) const |
| return override actuation More...
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const double & | get_min_control () const |
| Get the value of the min_control property. More...
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double & | upd_min_control () |
| Get a writable reference to the min_control property. More...
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void | set_min_control (const double &value) |
| Set the value of the min_control property. More...
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const double & | get_max_control () const |
| Get the value of the max_control property. More...
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double & | upd_max_control () |
| Get a writable reference to the max_control property. More...
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void | set_max_control (const double &value) |
| Set the value of the max_control property. More...
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void | assign (Object &aObject) override |
| This allows copy assignment in the Java GUI. More...
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| Actuator () |
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virtual const SimTK::Vector | getDefaultControls () |
| Actuator default controls are zero. More...
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virtual const SimTK::VectorView_< double > | getControls (const SimTK::State &s) const |
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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...
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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...
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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...
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void | assign (Object &aObject) override |
| This allows copy assignment in the Java GUI. More...
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virtual bool | shouldBeParallelized () const |
| Tell Simbody to parallelize this force. More...
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bool | appliesForce (const SimTK::State &s) const |
| Return if the Force is applied (or enabled) or not. More...
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void | setAppliesForce (SimTK::State &s, bool applyForce) const |
| Set whether or not the Force is applied. More...
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SimTK::ForceIndex | getForceIndex () const |
| Return the index to the SimTK::Force in the underlying system. More...
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const bool & | get_appliesForce () const |
| Get the value of the appliesForce property. More...
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bool & | upd_appliesForce () |
| Get a writable reference to the appliesForce property. More...
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void | set_appliesForce (const bool &value) |
| Set the value of the appliesForce property. More...
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void | assign (Object &aObject) override |
| This allows copy assignment in the Java GUI. More...
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| ModelComponent () |
| Default constructor. More...
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| ModelComponent (const std::string &aFileName, bool aUpdateFromXMLNode=true) |
| Construct ModelComponent from an XML file. More...
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| ModelComponent (SimTK::Xml::Element &aNode) |
| Construct ModelComponent from a specific node in an XML document. More...
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virtual | ~ModelComponent () |
| Destructor is virtual to allow concrete model component cleanup. More...
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void | connectToModel (Model &model) |
| Connect this ModelComponent to its aggregate- a Model. More...
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const Model & | getModel () const |
| Get a const reference to the Model this component is part of. More...
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Model & | updModel () |
| Get a modifiable reference to the Model this component is part of. More...
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bool | hasModel () const |
| Does this ModelComponent have a Model associated with it? More...
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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...
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void | scale (const SimTK::State &s, const ScaleSet &scaleSet) |
| Scale the ModelComponent. More...
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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...
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void | assign (Object &aObject) override |
| This allows copy assignment in the Java GUI. More...
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| Component () |
| Default constructor. More...
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| Component (const std::string &aFileName, bool aUpdateFromXMLNode=true) |
| Construct Component from an XML file. More...
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| Component (SimTK::Xml::Element &aNode) |
| Construct Component from a specific node in an XML document. More...
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| Component (const Component &)=default |
| Use default copy constructor and assignment operator. More...
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Component & | operator= (const Component &)=default |
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virtual | ~Component ()=default |
| Destructor is virtual to allow concrete Component to cleanup. More...
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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...
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const SimTK::MultibodySystem & | getSystem () const |
| Get the underlying MultibodySystem that this component is connected to. More...
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bool | hasSystem () const |
| Check if this component has an underlying MultibodySystem. More...
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bool | isComponentInOwnershipTree (const Component *component) const |
| Does the provided component already exist anywhere in the ownership tree (not just subcomponents of this component)? More...
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void | addComponent (Component *subcomponent) |
|
Add a Component (as a subcomponent) of this component. More...
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template<typename T = Component> |
ComponentList< const T > | getComponentList () const |
| Get an iterator through the underlying subcomponents that this component is composed of. More...
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template<typename T = Component> |
ComponentList< T > | updComponentList () |
| Similar to getComponentList(), except the resulting list allows one to modify the components. More...
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template<typename T = Component> |
unsigned | countNumComponents () const |
| Uses getComponentList<T>() to count the number of underlying subcomponents of the specified type. More...
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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...
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ComponentPath | getAbsolutePath () const |
| Return a ComponentPath of the absolute path of this Component. More...
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std::string | getRelativePathString (const Component &wrt) const |
| Get the relative path of this Component with respect to another Component, as a string. More...
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ComponentPath | getRelativePath (const Component &wrt) const |
| Get the relative path of this Component with respect to another Component. More...
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bool | hasComponent (const std::string &pathname) const |
| Query if there is a component (of any type) at the specified path name. More...
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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...
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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...
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template<class C = Component> |
const C & | getComponent (const ComponentPath &pathname) const |
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const Component & | getComponent (const std::string &pathname) const |
| Similar to the templatized getComponent(), except this returns the component as the generic Component type. More...
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template<class C = Component> |
C & | updComponent (const std::string &name) |
| Get a writable reference to a subcomponent. More...
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template<class C = Component> |
C & | updComponent (const ComponentPath &name) |
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Component & | updComponent (const std::string &pathname) |
| Similar to the templatized updComponent(), except this returns the component as the generic Component type. More...
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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...
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int | getNumStateVariables () const |
| Get the number of "continuous" state variables maintained by the Component and its subcomponents. More...
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Array< std::string > | getStateVariableNames () const |
| Get the names of continuous state variables maintained by the Component and its subcomponents. More...
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Array< std::string > | getDiscreteVariableNames () const |
| Get the names of discrete state variables maintained by the Component and its subcomponents. More...
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Array< std::string > | getModelingOptionNames () const |
| Get the names of the modeling options maintained by the Component and its subcomponents. More...
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void | finalizeFromProperties () |
| Define a Component's internal data members and structure according to its properties. More...
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void | finalizeConnections (Component &root) |
| Satisfy the Component's connections specified by its Sockets and Inputs. More...
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void | clearConnections () |
| Disconnect/clear this Component from its aggregate component. More...
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void | addToSystem (SimTK::MultibodySystem &system) const |
| Have the Component add itself to the underlying computational System. More...
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void | initStateFromProperties (SimTK::State &state) const |
| Initialize Component's state variable values from its properties. More...
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void | setPropertiesFromState (const SimTK::State &state) |
| Set Component's properties given a state. More...
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int | getNumSockets () const |
| Get the number of Sockets in this Component. More...
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std::vector< std::string > | getSocketNames () const |
| Collect and return the names of the sockets in this component. More...
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template<typename T > |
const T & | getConnectee (const std::string &name) const |
| Get the "connectee" object that the Component's Socket is bound to. More...
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template<typename T > |
const T & | getConnectee (const std::string &name, int index) const |
| Get the "connectee" object at the provided index that the Component's Socket is bound to. More...
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const Object & | getConnectee (const std::string &name) const |
| Get the connectee as an Object. More...
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const Object & | getConnectee (const std::string &name, int index) const |
| Get the connectee at the provided index as an Object. More...
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const AbstractSocket * | tryGetSocket (const std::string &name) const |
| Returns a pointer to the AbstractSocket with a given socket name, or nullptr if the socket with the given name does not exist on the component. More...
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const AbstractSocket & | getSocket (const std::string &name) const |
| Get an AbstractSocket for the given socket name. More...
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const AbstractSocket * | tryUpdSocket (const std::string &name) |
| Returns a writable pointer to the AbstractSocket with a given socket name, or nullptr if the socket with the given name does not exist on the component. More...
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AbstractSocket & | updSocket (const std::string &name) |
| Get a writable reference to the AbstractSocket for the given socket name. More...
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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...
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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...
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int | getModelingOption (const SimTK::State &state, const std::string &path) const |
| Based on a specified path, get the value of a modeling option. More...
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int | getModelingOption (const SimTK::State &state, const ComponentPath &path) const |
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void | setModelingOption (SimTK::State &state, const std::string &path, int flag) const |
| Based on a specified path, set the value of a modeling option. More...
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void | setModelingOption (SimTK::State &state, const ComponentPath &path, int flag) const |
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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...
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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...
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double | getStateVariableValue (const SimTK::State &state, const std::string &name) const |
| Get the value of a state variable allocated by this Component. More...
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double | getStateVariableValue (const SimTK::State &state, const ComponentPath &path) const |
| Get the value of a state variable allocated by this Component. More...
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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...
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SimTK::Vector | getStateVariableValues (const SimTK::State &state) const |
| Get all values of the state variables allocated by this Component. More...
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void | setStateVariableValues (SimTK::State &state, const SimTK::Vector &values) const |
| Set all values of the state variables allocated by this Component. More...
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double | getStateVariableDerivativeValue (const SimTK::State &state, const std::string &name) const |
| Get the value of a state variable derivative computed by this Component. More...
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double | getStateVariableDerivativeValue (const SimTK::State &state, const ComponentPath &path) const |
| Get the value of a state variable derivative computed by this Component. More...
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void | assign (Object &aObject) override |
| This allows copy assignment in the Java GUI. More...
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int | getNumInputs () const |
| Access the number of Inputs that this component has. More...
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int | getNumOutputs () const |
| Access the number of Outputs that this component has. More...
|
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std::vector< std::string > | getInputNames () const |
| Collect and return the names of Inputs in this component as an std::vector. More...
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std::vector< std::string > | getOutputNames () const |
| Collect and return the names of Outputs in this component as an std::vector. More...
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const AbstractInput & | getInput (const std::string &name) const |
| Get an Input provided by this Component by name. More...
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AbstractInput & | updInput (const std::string &name) |
| Get a writable reference to an Input provided by this Component by name. More...
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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...
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const AbstractOutput * | tryGetOutput (const std::string &name) const |
| If it exists on the component, returns a pointer to the named Output ; otherwise, returns a nullptr . More...
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const AbstractOutput & | getOutput (const std::string &name) const |
| Get the Output provided by this Component by name. More...
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AbstractOutput * | tryUpdOutput (const std::string &name) |
| If it exists on the component returns a writable pointer to the named Output ; otherwise, returns a nullptr More...
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AbstractOutput & | updOutput (const std::string &name) |
| Get a writable reference to an Output provided by this Component by name. More...
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SimTK::IteratorRange< OutputConstIterator > | getOutputs () const |
| Iterate through all Outputs of this component. More...
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virtual | ~Object () |
| Virtual destructor for cleanup. More...
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bool | isEqualTo (const Object &aObject) const |
| Equality operator wrapper for use from languages not supporting operator overloading. More...
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Object & | operator= (const Object &aObject) |
| Copy assignment copies he base class fields, including the properties. More...
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virtual bool | operator== (const Object &aObject) const |
| Determine if two objects are equal. More...
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virtual bool | operator< (const Object &aObject) const |
| Provide an ordering for objects so they can be put in sorted containers. More...
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void | setName (const std::string &name) |
| Set the name of the Object. More...
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const std::string & | getName () const |
| Get the name of this Object. More...
|
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void | setDescription (const std::string &description) |
| Set description, a one-liner summary. More...
|
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const std::string & | getDescription () const |
| Get description, a one-liner summary. More...
|
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const std::string & | getAuthors () const |
| Get Authors of this Object. More...
|
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void | setAuthors (const std::string &authors) |
| Set Authors of this object. More...
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const std::string & | getReferences () const |
| Get references or publications to cite if using this object. More...
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void | setReferences (const std::string &references) |
| Set references or publications to cite if using this object. More...
|
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int | getNumProperties () const |
| Determine how many properties are stored with this Object. More...
|
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const AbstractProperty & | getPropertyByIndex (int propertyIndex) const |
| Get a const reference to a property by its index number, returned as an AbstractProperty. More...
|
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AbstractProperty & | updPropertyByIndex (int propertyIndex) |
| Get a writable reference to a property by its index number, returned as an AbstractProperty. More...
|
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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...
|
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const AbstractProperty & | getPropertyByName (const std::string &name) const |
| Get a const reference to a property by its name, returned as an AbstractProperty. More...
|
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AbstractProperty & | updPropertyByName (const std::string &name) |
| Get a writable reference to a property by its name, returned as an AbstractProperty. More...
|
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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...
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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...
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template<class T > |
const Property< T > & | getPropertyByName (const std::string &name) const |
| Get property of known type Property<T> as a const reference; the property must be present and have the right type. More...
|
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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...
|
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template<class T > |
Property< T > & | updPropertyByName (const std::string &name) |
| Get property of known type Property<T> as a writable reference; the property must be present and have the right type.
More...
|
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bool | isObjectUpToDateWithProperties () const |
| Returns true if no property's value has changed since the last time setObjectIsUpToDateWithProperties() was called. More...
|
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void | readObjectFromXMLNodeOrFile (SimTK::Xml::Element &objectElement, int versionNumber) |
| We're given an XML element from which we are to populate this Object. More...
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void | updateXMLNode (SimTK::Xml::Element &parent, const AbstractProperty *prop=nullptr) const |
| Serialize this object into the XML node that represents it. More...
|
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bool | getInlined () const |
| Inlined means an in-memory Object that is not associated with an XMLDocument. More...
|
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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...
|
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std::string | getDocumentFileName () const |
| If there is a document associated with this object then return the file name maintained by the document. More...
|
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int | getDocumentFileVersion () const |
| If there is a document associated with this object then return its version number. More...
|
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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...
|
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std::string | dump () const |
| dump the XML representation of this Object into an std::string and return it. More...
|
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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...
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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...
|
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PropertySet & | getPropertySet () |
| OBSOLETE: Get a reference to the PropertySet maintained by the Object. More...
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const PropertySet & | getPropertySet () const |
|
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double | getStateVariableDeriv (const SimTK::State &s, const std::string &aStateName) const |
| Gets the derivative of an actuator state by index. More...
|
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void | setStateVariableDeriv (const SimTK::State &s, const std::string &aStateName, double aValue) const |
| Sets the derivative of an actuator state specified by name. More...
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|
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...
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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...
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|
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...
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void | calcMusclePotentialEnergyInfo (const SimTK::State &s, MusclePotentialEnergyInfo &mpei) const override |
| Calculate the potential energy values associated with the muscle. More...
|
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void | extendConnectToModel (Model &model) override |
| Sets up the ModelComponent from the model, if necessary. More...
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void | extendAddToSystem (SimTK::MultibodySystem &system) const override |
| Creates the ModelComponent so that it can be used in simulation. More...
|
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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...
|
|
const MuscleLengthInfo & | getMuscleLengthInfo (const SimTK::State &s) const |
| Developer Access to intermediate values calculate by the muscle model. More...
|
|
MuscleLengthInfo & | updMuscleLengthInfo (const SimTK::State &s) const |
|
const FiberVelocityInfo & | getFiberVelocityInfo (const SimTK::State &s) const |
|
FiberVelocityInfo & | updFiberVelocityInfo (const SimTK::State &s) const |
|
const MuscleDynamicsInfo & | getMuscleDynamicsInfo (const SimTK::State &s) const |
|
MuscleDynamicsInfo & | updMuscleDynamicsInfo (const SimTK::State &s) const |
|
const MusclePotentialEnergyInfo & | getMusclePotentialEnergyInfo (const SimTK::State &s) const |
|
MusclePotentialEnergyInfo & | updMusclePotentialEnergyInfo (const SimTK::State &s) const |
|
virtual double | calcMuscleStiffness (const SimTK::State &s) const |
| Calculate muscle's stiffness. More...
|
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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...
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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...
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void | extendAddToSystem (SimTK::MultibodySystem &system) const override |
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void | extendSetPropertiesFromState (const SimTK::State &s) override |
|
void | extendInitStateFromProperties (SimTK::State &state) const override |
|
virtual void | updateGeometry (const SimTK::State &s) |
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void | extendRealizeDynamics (const SimTK::State &state) const override |
| Extension of parent class method; derived classes may extend further. More...
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void | extendAddToSystem (SimTK::MultibodySystem &system) const override |
|
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...
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void | extendAddToSystem (SimTK::MultibodySystem &system) const override |
|
| Force () |
| Default constructor sets up Force-level properties; can only be called from a derived class constructor. More...
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| Force (SimTK::Xml::Element &node) |
| Deserialization from XML, necessary so that derived classes can (de)serialize. More...
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void | extendInitStateFromProperties (SimTK::State &state) const override |
| Subclass should override; be sure to invoke Super::extendInitStateFromProperties() at the beginning of the overriding method. More...
|
|
void | extendAddToSystem (SimTK::MultibodySystem &system) const override |
| Default is to create a ForceAdapter which is a SimTK::Force::Custom as the underlying computational component. More...
|
|
void | extendSetPropertiesFromState (const SimTK::State &state) override |
| Subclass should override; be sure to invoke Force::extendSetPropertiesFromState() at the beginning of the overriding method. More...
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|
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...
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|
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...
|
|
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 |
|
const Component & | get_components (int i) const |
| Get the value of the i-th element of the components property. More...
|
|
Component & | upd_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...
|
|
| Object () |
| The default constructor is only for use by constructors of derived types. More...
|
|
| Object (const std::string &fileName, bool aUpdateFromXMLNode=true) |
| Constructor from a file, to be called from other constructors that take a file as input. More...
|
|
| Object (const Object &source) |
| Copy constructor is invoked automatically by derived classes with default copy constructors; otherwise it must be invoked explicitly. More...
|
|
| Object (SimTK::Xml::Element &aElement) |
| Construct the base class portion of an Object from a given Xml element that describes this Object. More...
|
|
template<class T > |
PropertyIndex | addProperty (const std::string &name, const std::string &comment, const T &value) |
| Define a new single-value property of known type T, with the given name, associated comment, and initial value. More...
|
|
template<class T > |
PropertyIndex | addOptionalProperty (const std::string &name, const std::string &comment) |
| Add an optional property, meaning it can contain either no value or a single value. More...
|
|
template<class T > |
PropertyIndex | addOptionalProperty (const std::string &name, const std::string &comment, const T &value) |
| Add an optional property, meaning it can contain either no value or a single value. More...
|
|
template<class T > |
PropertyIndex | addListProperty (const std::string &name, const std::string &comment, int minSize, int maxSize) |
| Define a new list-valued property of known type T, with the given name, associated comment, minimum (==0) and maximum (>0) allowable list lengths, and a zero-length initial value. More...
|
|
template<class T , template< class > class Container> |
PropertyIndex | addListProperty (const std::string &name, const std::string &comment, int minSize, int maxSize, const Container< T > &valueList) |
| Define a new list-valued property as above, but assigning an initial value via some templatized container class that supports size() and indexing. More...
|
|
PropertyIndex | getPropertyIndex (const std::string &name) const |
| Look up a property by name and return its PropertyIndex if it is found. More...
|
|
template<class T > |
PropertyIndex | getPropertyIndex () const |
| Look up an unnamed property by the type of object it contains, and return its PropertyIndex if it is found. More...
|
|
template<class T > |
void | checkPropertyValueIsPositive (const Property< T > &p) const |
| Throw an exception if any of the property's values are not positive. More...
|
|
template<class T > |
void | checkPropertyValueIsInSet (const Property< T > &p, const std::set< T > &set) const |
| Throw an exception if any of the property's values are not in the provided set. More...
|
|
template<class T > |
void | checkPropertyValueIsInRangeOrSet (const Property< T > &p, const T &lower, const T &upper, const std::set< T > &set) const |
| Throw an exception if any of the property's values are neither in the provided range nor in the provided set. More...
|
|
void | setObjectIsUpToDateWithProperties () |
| When an object is initialized using the current values of its properties, it can set a flag indicating that it is up to date. More...
|
|
void | clearObjectIsUpToDateWithProperties () |
| For testing or debugging purposes, manually clear the "object is up to
date with respect to properties" flag. More...
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void | makeObjectNamesConsistentWithProperties () |
| Make sure the name of an object is consistent with its property type. More...
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void | updateFromXMLDocument () |
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void | setDocument (XMLDocument *) |
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const XMLDocument * | getDocument () const |
| Get a const pointer to the document (if any) associated with this object. More...
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XMLDocument * | updDocument () |
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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:
\[ f_{ISO}\Big(\mathbf{a}(t) \mathbf{f}_L(\hat{l}_{CE}) \mathbf{f}_V(\hat{v}_{CE}) + \mathbf{f}_{PE}(\hat{l}_{CE}) + \beta \hat{v}_{CE}\Big) \cos \phi - f_{ISO}\mathbf{f}_{SE}(\hat{l}_{T}) = 0 \]
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;
double optimalFiberLength = 0.025;
double tendonSlackLength = 0.25;
double pennationAngle = 0.5;
bool ignoreTendonCompliance = false;
bool ignoreActivationDynamics = false;
double dampingCoefficient = 0.001;
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